# Gemmy skull lantern hack



## Dr Morbius

I want to hack this lantern so it can banter between it and another prop I have. Does anyone else have this?









I would like to use this circuit. Has anyone used this before?










Here is a video of the lantern as it is intended to be used.

hw0604.wmv video by DrMorbius02 - [email protected]@[email protected]@http://vid23.photobucket.com/player.swf?file=http://vid23.photobucket.com/albums/b364/DrMorbius02/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@b364/DrMorbius02/hw0604

I'll go ahead and experiment, but I was hoping to get some advice from anyone who has done this type of thing before.

Thanks in advance.


----------



## Hauntiholik

Doc - that's the circuit that I'm using for my skull chandelier. I'm having issues with it. Greencapt was able to build the circuit and get it to work but he had to use an amplified source for his test.

oops, forgot the link. http://www.hauntforum.com/showthread.php?t=6645


----------



## Dr Morbius

Thanks Haunti...I got the drawing from your chandelier link, thank you.
Does anyone have an alternative circuit?


----------



## Dr Morbius

Well, I isolated the jaw and LED eye wires, and tested them on a seperate power source..so far so good! I may just use my bridge rectifier and power the jaw directly off an amplified speaker channel.


----------



## Lilly

Cool I have a lantern like that.. keep us post Doc...
maybe I'll have to get another.
do you do the voices then ?


----------



## Dr Morbius

Here is a vid of the lantern apart and the wires I hacked:
lantern hacked.mpg video by DrMorbius02 - [email protected]@[email protected]@http://vid23.photobucket.com/player.swf?file=http://vid23.photobucket.com/albums/b364/DrMorbius02/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@b364/DrMorbius02/lanternhacked-1

Here is one with the hack working manually:
gemmy lantern.mpg video by DrMorbius02 - [email protected]@[email protected]@http://vid23.photobucket.com/player.swf?file=http://vid23.photobucket.com/albums/b364/DrMorbius02/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@b364/DrMorbius02/gemmylantern


----------



## Front Yard Fright

Looking good Doc!
.


----------



## slimy

Let us know what you come up with, Doc.

Looks good by the way.


----------



## Hauntiholik

Doc - In your first vid, did you just remove the jaw and LED wires from the board?


----------



## Dr Morbius

Yes. I just clipped them from the board and spliced them together and attached my own wire to make them longer so I could solder them to the battery housing. This prop was MADE to be hacked. It couldn't be simpler, as all three pairs of wires you need are easily accessable. The pair for the jaw, the pair for the LED eyes, and there is also a pink pair of wires for the LED spots. Those I will use with a seperate controller as I don't want them to flash in sync with the jaw.


----------



## Hauntiholik

Is there a speaker in the lantern? Will you be using it in your hack?


----------



## Dr Morbius

There are two, actually. One regular coil speaker and a Pizo-electric one. Not sure why, but it's there. So no, I'll be using a seperate amplified source that sounds much better, as it will talk to WIlfred who will be on a amplified source as well, and they need to be at the same volume.


----------



## Dr Morbius

Well, using my bridge rectifier with a speaker voltage didn't work. I have the parts for the circuit diagram Haunti linked to, so I'll try that next. Wish me luck!


----------



## Lilly

Good Luck Doc!!!


----------



## Dr Morbius

Lilly said:


> Cool I have a lantern like that.. keep us post Doc...
> maybe I'll have to get another.
> do you do the voices then ?


Yes, I will do 'da voysesssss! LOL!


----------



## Dr Morbius

OK, I built the toy motor circuit. It works, but with some unexpected results. Only one LED eye lights. Both light when I just short the power wires to them directly. It needs Fully charged, fresh batteries. The older ones wouldn't cut it, it takes 3 AA batteries. It is NOISEY...you can hear the audio channel buzzing through the jaw motor. I wonder if I can shunt a resistor to the LED eyes, so that more power can go to the jaw. I don't know much about electronics, but I'm thinking the resistor will probably just draw the current and expell it as heat. Any suggestions? I'll post a vid in a couple hours.


----------



## Dr Morbius

LOL! Oh man, I wish I used that resistor on the LED eyes, cause now they are burned out. I guess they weren't designed to withstand the direct full current of 3 AA batteries. So, one burned out, then the other. I'll replace them with blue, maybe, if I can find them.


----------



## Hauntiholik

Ugh! Sorry to hear about the LEDs. I haven't attempted to wire them up yet.


----------



## Dr Morbius

The circuit works fine, but check the current/voltage requirements of your LEDS, or you might burn em out. Use a resistor if needed. Also, use a wall wart as the batteries go dead fast.


----------



## Hauntiholik

The walwart I got was for 6 volts and the circuit needs something closer to 4 volts.


----------



## Dr Morbius

You mean the toy motor circuit? I THINK it'll run whatever voltage your original prop runs at. But you're using more than one, so I don't know what your voltage requirements are. I tapped into the speaker wires on an old boombox I got at a thrift store for 3 bucks. It works well with the toymotor circuit, even at lower volumes,( according to the LED spots I cut into, after the eyes burned out), but the prop I have needs a good strong 4.5 volts to run well.


----------



## Hauntiholik

Yeah, the toy motor circuit.
At the moment I'm just working on one skull. I figured that the higher voltage fried the circuit because the jaw wasn't moving properly with the audio input.


----------



## Dr Morbius

OOooo maybe it did. What current does your wall wart put out?


----------



## Hauntiholik

Dr Morbius said:


> OOooo maybe it did. What current does your wall wart put out?


6V, 1500mA


----------



## Dr Morbius

That's 1.5 amps..Are you using the same wallwart that came with your skull?


----------



## Hauntiholik

My skull didn't come with a walwart. It was powered by 3 AA batteries.


----------



## Dr Morbius

Yikes! Yup, you're using WAY too much voltage! Build another (they're cheap) and try it again with just the batteries. Or a 4.5 V wallwart. Also, you need a good audio source, you can't use lineout voltage, you need amplified speaker terminals. Also, regular unamplified (and some poorly amplified) computer speakers won't work. You need something with som volume to it,like a boombox, or a home stereo.


----------



## Hauntiholik

I used a home stereo and the batteries and the jaw just vibrated without opening.


----------



## Dr Morbius

Sorry to hear that, Haunti, I wish I could help, but I'm outta ideas as to what went wrong. Maybe someone else can chime in with an answer?
Well, here is a vid I took, it's working with the cheapo boombox, and the jaw is moving to the beat of a tune. Just an experiment, I haven't written or recorded any dialog yet.

gemmytunes video by DrMorbius02 - [email protected]@[email protected]@http://vid23.photobucket.com/player.swf?file=http://vid23.photobucket.com/albums/b364/DrMorbius02/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@b364/DrMorbius02/gemmytunes


----------



## Dr Morbius

Did you try it without the speaker hooked up?


----------



## Dr Morbius

ok, in the future, if anybody tries this, measure the voltage with a multimeter to the LEDS when it is normally operating..before hooking it up the toy motor circuit...big DUH on my part. Then insert the proper resistors so as not to burn them out like I did. Oh weel, live and learn. Now I have more work to do on it, but fortunatly, it wont be hard.


----------



## Troy

Maybe I'm not understanding here (can't see the pics at work) but didn't the Skull come with a mic input?? The one I scored did, I took the Skull out of the lantern and applied some latex, changed they eyes & added some hair. 

To drive the Skull I bought a dubbing cord (1/8" plugs on both ends), used a 1/8" to 1/4" adapter so i could plug the one end into the mic input, the jaw/Eyes work flawlessly with either a MP3 Player or portable CD player. Gonna make a grave digger out of it.


----------



## Dr Morbius

If yours came with a mic input, then great! You won't need to hack it, I wish mine did, but it didn't.


----------



## Troy

Dr Morbius said:


> If yours came with a mic input, then great! You won't need to hack it, I wish mine did, but it didn't.


Oh ok gotcha...I should have known better!


----------



## Dr Morbius

Hauntiholik said:


> I used a home stereo and the batteries and the jaw just vibrated without opening.


Haunti, did you reverse the polarity of the toymotor circuit wires to the jaw? Maybe the motor was running backwards, and vibrated instead of moving the jaw?


----------



## Zombie-F

Troy said:


> Maybe I'm not understanding here (can't see the pics at work) but didn't the Skull come with a mic input??


Wow, Gemmy is just really all over the place with this issue aren't they? Why is it some of their stuff has the mic input and other items don't? Even with the same item, sometimes it does and sometimes it doesn't.

I'd be willing to bet that on every circuit board in these things, the artwork for the mic input is probably there. If a tech-savvy person could get their hands on both versions and compare, I bet we could have a components list generated and add the proper components... unless of course, it's all surface mount. Then only those of us with surface mount soldering skills/tools could do it.

I like this prop. I hope you can get the bugs worked out Dr and get it up and running smoothly.


----------



## randyaz

If the original runs on 3 batteries thats 4.5 volts. Since your getting life out of the circuit it may be the 6v is making the motor run to fast and getting to much response. On the amps, too little amps/current will cause problems but a device will only draw the amps/current it needs to run so you cant really have to much. 

I dont have a skull prop but i have a small 6v motor and got it to work...


----------



## Dr Morbius

Ok, I replaced the LEDS, and thanks to Zombie F I got the right resistors on it and it runs real good now. I replaced the blue LEDS with yellow ones, as the blue ones are 5 bucks EACH and I can't see spending more on this project than the prop is worth. Now I need to find a 4.5V adapter. Anyone know the current (Amps) equivalent to 3 AA batteries?


----------



## Dr Morbius

Zombie-F said:


> Wow, Gemmy is just really all over the place with this issue aren't they? Why is it some of their stuff has the mic input and other items don't? Even with the same item, sometimes it does and sometimes it doesn't.
> 
> I'd be willing to bet that on every circuit board in these things, the artwork for the mic input is probably there. If a tech-savvy person could get their hands on both versions and compare, I bet we could have a components list generated and add the proper components... unless of course, it's all surface mount. Then only those of us with surface mount soldering skills/tools could do it.
> 
> I like this prop. I hope you can get the bugs worked out Dr and get it up and running smoothly.


Even if it DID have a mic input, I'd hate to be stuck with the tiny tinny speaker that comes with it. But you're right, Z it would be interesting to see if the board could be dissected to uncover an unused mic input. I've been going over the old board I pulled out of the skull lantern, and where my knowledge is quite limited, I don't see any un-used spots where a mic might gh, and this one isn't surface mount, but it DOES have a little epoxy "dot" they use for a chip. Other than that, all discreet components.


----------



## Dr Morbius

Ok, I reversed the polarity of the motor, and it seemed to help. Alot. It sounds like a cash register, the motor is noisy. It can't be helped, but it's OK, it will be at a distance and with the new sound track, it shouldn't have echo that makes it vibrate like that. Also, the eye LEDS fell back into the skull as I didn't glue them in yet. I actually like the way they lightup the inside of the skull, so I may just keep it that way. Here it is, all ready to be mounted to my "other" prop!

skulllanternleds video by DrMorbius02 - [email protected]@[email protected]@http://vid23.photobucket.com/player.swf?file=http://vid23.photobucket.com/albums/b364/DrMorbius02/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@b364/DrMorbius02/skulllanternleds


----------



## Hauntiholik

Dr Morbius said:


> Haunti, did you reverse the polarity of the toymotor circuit wires to the jaw? Maybe the motor was running backwards, and vibrated instead of moving the jaw?


I tried it both ways Doc. No joy.


----------



## Hauntiholik

randyaz said:


> I don't have a skull prop but i have a small 6v motor and got it to work...


You stinker!! I knew you'd get it to work.


----------



## Dr Morbius

I've been doing some experimentation with this prop..it works fine, but I found out some wierd things about the toy motor circuit. I tuned to a talk radio station on the boombox, just to see how it worked, and noticed the jaw moves perfectly to low timber male voices, but not female ones. The male talkshow host activated the jaw fine, but the people who phoned in only activated the LEDS....?????????

I think the circuit is haunted. I'll take a vid of this phenomenon soon.


----------



## Sickie Ickie

oooooooooooooooo spoooooooooooooooookeyyyyyyyyyyy


----------



## Dr Morbius

I reallly need an answer to this question, So, if ANYBODY can answer this, Zombie? Otaku? The DC motor in my Gemmy prop has 3 small disc capacitors across it's terminals. Would these limit the switching, looking at the circuit I posted, to a certain frequency? I'm thinking I should remove them. Anybody?


----------



## Hauntiholik

I wondered about those capacitors as well. Since greencapt kept them in his talking skull I assumed that they should be left in.

Dang. This is really taxing my memory. The lower male voice would have a greater wavelength than the female voice. 
f * λ = c
f = frequency in Hertz (Hz = 1/sec)
λ = wavelength in meters (m)
c = the speed of light and is approximately equal to 3*108 m/s 

On another note, I'm not the only one who can't get the circuit to work in a candy dish skull. So it's not that I wired it wrong, it's a problem with the skull or the design of the circuit for THAT skull.


----------



## Hauntiholik

I'm guessing that the circuit is more equipped to handle the lower end frequencies.


----------



## Dr Morbius

Do you have a link to GreenCapts skull?


----------



## Hauntiholik

http://halloweenforum.com/showthread.php?t=58133&page=2


----------



## Dr Morbius

Hmmm..It looks like he may have incorporated the BLACK wire from the audio transformer into the circuit somehow. I would like to know what he hooked it up to. I'll mess around with mine and see what happens.


----------



## Hauntiholik

The black wire should be ground right? I think he may have just soldiers it to the board because he didn't like loose wires.


----------



## SpookySam

I am working on exactly the same setup as Hauntiholik. It seems like there is just not quite enough power going to the motor from the replacement circuit board. If I lightly assist the motor during operation, the jaw will move as it should. 

I am going to tinker with it some more at my first convenience, but it may be that the circuit used by Greencapt simply won't work with the Skull Candy Dish motor. Hopefully, this is not the case.


----------



## SpookySam

Well, I've tried fresh batteries and a boom box at full volume. No luck. I have also reassembled the original circuit to see if I accidentally burned up the motor...it works fine. 

I am officially out of ideas.


----------



## Dr Morbius

SpookySam said:


> Well, I've tried fresh batteries and a boom box at full volume. No luck. I have also reassembled the original circuit to see if I accidentally burned up the motor...it works fine.
> 
> I am officially out of ideas.


LOL! This is maddening, isn't it? It SHOULD work for all frequencies, but it doesn't. Wierd!


----------



## SpookySam

Hey Doc...does your lantern skull work with a solenoid opening the jaw or does it have a motor reeling in line? I haven't seen any pictures of the inside of your setup, and I'm curious to see how similar it is to the skull candy dish. 

My setup is a lever on the jaw that is spring loaded to close automatically. There is a line from the lever that is attached to the shaft of a motor. As power is sent to the motor, it reels in the line, opening the jaw. How does yours compare?


----------



## Dr Morbius

Same as yours. A motor with a string.


----------



## Dr Morbius

well, the black wire, a center tap for the audio transformer, does nothing to help it, it just makes it weaker. I guess using a really good, clean, amplified source is the key to making this work well.


----------



## turtle2778

Doc, I LOOOOVE you choice in music. Here i thought i was the only one still listening to Kool and the Gang. My kid treats me like im from another planet. LOL. Good luck on your hack.



Dr Morbius said:


> Sorry to hear that, Haunti, I wish I could help, but I'm outta ideas as to what went wrong. Maybe someone else can chime in with an answer?
> Well, here is a vid I took, it's working with the cheapo boombox, and the jaw is moving to the beat of a tune. Just an experiment, I haven't written or recorded any dialog yet.


----------



## SpookySam

I think I'm giving up on the Skull Candy Dish for my talking skull. Doc, I have tried the amplified source from a boom box and my Onkyo home stereo, so I know it is getting a powerful, clean signal. I've even hooked up the stereo lines directly to the motor leads to see if I could get any response...nothing.

I guess I can take comfort in the fact that I didn't destroy anything, though. I've reassembled the candy dish and it works fine.

I may still pick up one of these: http://hauntmasterproducts.com/16.html and use it with the candy dish. It seems that Slimy may have used it in this setup with success.


----------



## Dr Morbius

Sorry to hear it isn't working for the candydish skull. I wonder if anyone who has a motormouth has opened it up. It would be interesting to see the circuitry.


----------



## Dr Morbius

turtle2778 said:


> Doc, I LOOOOVE you choice in music. Here i thought i was the only one still listening to Kool and the Gang. My kid treats me like im from another planet. LOL. Good luck on your hack.


Don't mean to dissapoint, turtle, it was just a random song on the radio..It was just on at the time I took the video. Thanks for the good wishes!!


----------



## Hauntiholik

Darn.
I was wondering what the voltage from the original board to the motor was in comparison to the new board. I guess I'll check on that tonight.

With the motormouth it says it can power up to 2 props. I wonder if anyone had tried to power more than one and what happens. I really don't want to buy enough for 5 motors


----------



## Hauntiholik

I wired up the circuit on a test board using a variable resistance. I didn't notice an improvement in the jaw movement. GRRRRRRRR!


----------



## Dr Morbius

This is obviously frequency related. I wonder if the toy motor circuit is impeding the voltage somehow. Maybe the transformer isn't bumping up the source voltage enough? It seems that to convert the AC source speaker current to a DC switching current is chopping the available current to the motor, effetively cutting it in half..so the motor is only getting a half wave and causes it to jitter. I'm no expert, but I think maybe adding a second more powerful transformer, or adding more diodes to better rectify the signal to the transistors might help.


----------



## Hauntiholik

I should have paid more attention in EE101.


----------



## Hauntiholik

Doc - 
which diode did you use? 1N914 or 1N4148? Did you use the TIP 31A or TIP31 transistor?


----------



## Dr Morbius

The packages I bought have BOTH numbers on them. For example, the Transistors I got say TIP31 on the packaging and imprinted on the transistor itself it says TIP31A. The packaging for the diodes have both numbers on it and reads "1N914-1N4148". These must be entirely interchangeable, are the same parts, but with different nomenclacher due to different manufacturers.


----------



## SpookySam

Hauntiholik - I don't think the motor mouth could power 5 skulls, but what if you used the motor mouth to close relays for the 5 skulls? It might cause the jaw movement to be more jerky....I'm not sure. Just a thought.


----------



## Hauntiholik

Doc - leave the capacitors in. The capacitors are bypass caps and they help reduce the noise that the motor generates.

SpookySam - I'm still trying to figure out how to make the circuit work for my skulls. I hate failure.


----------



## Dr Morbius

Thanks Haunti..I kinda figured they were a filter of some sort. I hope you can get it to work..I've been fiddling with my audio source and mine is working quite well now. I'm modifying Wilfred to interact with it as we speak. Hop to have some progress pics up this weekend.


----------



## Hauntiholik

Thanks Doc! I've asked a few people about the issues I'm having.

One person suggested that the vibration I saw with the walwart was due to insufficient filtering on the wall wart supply. 

Another person said the circuit uses a stereo output rather than line level output. I had already found that our from GreenCapt when I couldn't get the circuit to work initially.

So far I think it's still the power supply. The batteries aren't enough to open the jaw and the walwart I was using to too much.


----------



## SpookySam

I picked up a talking skull at GardenRidge today. It looks just like the one from the talking skull candy dish, but I'm hoping they used a different motor for the jaw. I'm going to try this one out over the weekend and see if it acts any differently.


----------



## Hauntiholik

You know, the candy dish skull hack would make a good challenge. Whoever can get this ****** thing working (reliably) first would win!


----------



## SpookySam

Well, I tried this circuit on another gemmy skull. It is pictured below.









I was hoping it had a different motor, but the effects are the same.


----------



## .id.

Out of curiousity, what happens if you short the green and blue wires together that go to the transformer? Does the motor move correcly then? It should move to it's maximum extent....The two transistors form a Darlington pair (a smaller transistor is used to turn a bigger one on) and shorting the lines together would remove the audio transformer from the circuit and turn both transistors on..... Just a thought....


----------



## heresjohnny

Hey Doc, did you ever find anything else out about this circuit? Anybody? I have the Gemmy talking pair of skulls, and they have the motor on the jaw.


----------



## Dr Morbius

Mine seems to work VERY well using a PC ATX power supply. Before I was using an unregulated wall wart type supply. My conclusion is it takes two things to make this work well...a good clean amplified source and 5V regulated powersupply with ample current. I even managed to get 3 props singing off one Toy motor circuit, although the LEDS dim alot. My guess is there is a 2 prop limit for one Toy motor circuit.


----------



## Dr Morbius

.id. said:


> Out of curiousity, what happens if you short the green and blue wires together that go to the transformer? Does the motor move correcly then? It should move to it's maximum extent....The two transistors form a Darlington pair (a smaller transistor is used to turn a bigger one on) and shorting the lines together would remove the audio transformer from the circuit and turn both transistors on..... Just a thought....


i.d I haven't tried that, as I haven't needed to, but when I build my second one I'll give it a go and post the results here.


----------



## heresjohnny

Doc, do you think the circuit is a simplified color organ, i.e. it delivers 'pulses' of current in synch with sound?


----------



## loki13

I got a skull from Menards. It's not packaged as a Gemmy it's packaged as pumpkin hallow, but it's a gemmy skull. I think I have figured out where all the wires go. I think the sound chip is the 12 pin board with the little black blob on it. This board sound to be different from the ones that some of you have posted. Has anyone come across this board(KT-1930) 
MJ


----------



## Dr Morbius

the sound chip is indeed the one you described, mine has the same as I suspect most Gemmy's are. I have seen a post somewhere of someone hacking it, but I forget where I saw it. I opted for not doing that as the sound quality of the prop in general is poor at best. If I find it, I will post it here.


----------



## Dr Morbius

heresjohnny said:


> Doc, do you think the circuit is a simplified color organ, i.e. it delivers 'pulses' of current in synch with sound?


Hj, I would think it might..It takes the AC from the source and uses switching transistors to switch on the motor and LEDS from a seperate power source. I wouldn't be surprised if the output is chopped by the AC source input. Maybe if the input or output were rectified better to eliminate the halfwave of the AC signal it might work better.


----------



## loki13

*Thank you DR. M:voorhees: *


----------



## loki13

Einstein try to pm me now


----------



## heresjohnny

Okay, I'm gonna play with the circuit for driving the gemmy talking skulls some, and this seems like the thread to talk about it on. Have done a little preliminary research and have found:

1. I think the circuit is a Sziklai pair, which has a lower (.6 volts) switch on voltage than a Darlington pair.

2. I have seen where you use a 100 ohm resistor between the transistors to improve the high frequency response.

I have the parts, time to start playing!


----------



## Dr Morbius

I'm glad you are trying this with a gemmy skull...I have it working perfectly with the gemmy lantern AND TWO Target bride and groom skulls. Granted, the two skulls suck the current from the lantern LEDs but all three jaws work with one board. Now, my guess is that there is nothing wrong with the circuit, but rather the Gemmy skull may not be compatible. I still have no idea why, so please keep us posted on your progress, HJ!


----------



## heresjohnny

There are several color organ, or audio switch circuits out there, and they all seem to use a transformer for a speaker level input. Does anyone know how to modifya circuit with a speaker level input to use a line-level instead?


----------



## heresjohnny

I may have found something, a circuit a guy built to replace the one in the talking fish. I like it because it uses a line level input, and it uses the same input signal to control three things. That tells me that this may be suited to drive several skulls from the same signal, which was the original goal of the skull chandelier prop.

http://www.interaccess.org/telekinetics/template.php?show=The_Talking_Fish_Circuit


----------



## Dr Morbius

Looks like the second and third motors needs to have the CAP and Diode removed so they behave like the top circuit, otherwise they won't be in sync to the audio input, since they are hooked up to make the fishes body twitch, but I like the circuit because it is adjustable. Interesting!


----------



## heresjohnny

I did not have much luck with the first circuit http://home.rica.net/jimk/projects/servo/index.htm and this seems consistent with what I was reading here. I use the amplified output of an external computer speaker, and at top volume I was just starting to get a response, I don't want to have to blast a stereo to get this to work. I want to try the fish circuit now, I have high hopes for this one. If it does not work, scary terry has a circuit also that I would like to try http://www.scary-terry.com/audiodriver/audiodriver.htm.

The thing I like about the fish circuit is it shows how you can use a single line input and do different things; I think you could just keep repeating the top circuit for multiple skulls that are saying the same thing. You can also do what he did, which was have a second circuit at a different trigger level so the body and tail would move differently than the mouth moving.


----------



## Dr Morbius

You DO need a good amplifier to make that first circuit work. I used a powered computer amp with subwoofer (off because it plays both channels at once). I think you need to consider the current the amp puts out. I don't need to turn my sound all the way up to make it work either. Also, you need a GOOD power supply. My ATX computer power supply at 5 volts was enough to power 3 props on the first circuit everyone (but me it seems) is having problems with. Also, HJ if you don't want that first circuit send it to me! I love them..LOL!


----------



## heresjohnny

Dr Morbius said:


> You DO need a good amplifier to make that first circuit work. I used a powered computer amp with subwoofer (off because it plays both channels at once). I think you need to consider the current the amp puts out. I don't need to turn my sound all the way up to make it work either. Also, you need a GOOD power supply. My ATX computer power supply at 5 volts was enough to power 3 props on the first circuit everyone (but me it seems) is having problems with. Also, HJ if don't want the that first circuit send it to me! I love them..LOL!


A couple of things you say are key, one the power supply, and two the amp that feeds the input signal. I am driving it with 6 volts (4 AA batteries), and the amp is what comes with a basic pair of computer speakers. It's startng to respond, but i'd rather find someting that works line level, and is more efficient with the power supply. The gemmy pair of skulls run off 4 AA batteries, I would think an ATX power supply could drive 20 skulls. Also, on my circuit, the transformer gets hot.


----------



## Dr Morbius

Try ditching the batteries and hooking up an ATX. Use the 5 volts, it's 1 volt short of what the skull needs but it should still work. Your circuit may be trying to pull more current than your batteries can handle. I think I'm the only one who has tried the toy motor circuit with an ATX supply, so I'd like to know if it works for you or not.


----------



## heresjohnny

Okay, that would be worth confirming.


----------



## Dr Morbius

HJ, any luck with the ATX supply on your skull?


----------



## heresjohnny

<heresjohnny gasps as he finally axes through the door> I am gonna try and get the talking fish circuit put together tonight. Sorry Dr. M, but based on what I have read and experienced, I don't want to spend much time on the other circuit that requires an amplified input.


----------



## Dr Morbius

No worries! Post your circuit results when you get it built..I'm curious how well it works.


----------



## heresjohnny

I got the circuit put together, connected it to one of the skulls from the gemmy pair of talking skulls, and it worked! One nice thing about the circuit is you can leave off the 1k resistor, transistor and motor, and test with just the LED. I got that working first, then connected the motor and got that working. The overall effect when adjusted right is good.

But..it's noisy. With the gain turned up high enough to drive the skull you can hear a very distorted version of the sound source coming from the motor. Not sure why, I am guessing it has something to do with a lot of the sound signal being amplified and sent to the motor. I think I can filter it out.

The first time I tried it was with older batteries (4 AA) and they could not drive the jaw, it would only vibrate. This reminds me off what Dr M found to be a power supply problem, so I tried fresh AA batteries and it started working. I think the final version will use a computer power supply, again like Dr. M. suggested.

I used a 10k pot, and it was very sensitive, so I will try a smaller pot, and maybe the voltage divider like in the second circuit.

Overall, it works off a little mp3 player, and you can keep a powered speaker hooked up to the input without affecting the circuit or the sound quality. You can split a single input across multiple op amps. I have 3 gemmy skulls (1 candy dish skull and the talking pair), so I am going to try and solve the noise problem, then try and drive all 3 from a single mp3 source.


----------



## heresjohnny

Okay, a low pass filter seems pretty simple, I will try it tomorrow.
http://en.wikipedia.org/wiki/Low-pass_filter


----------



## Dr Morbius

I get noise from the motor too. I'm thinking there's no way around it if you are using a rectified amplified sound source as power. Any filter may limit the current needed to operate the motor, but that's just my guess, I haven't tried it, but I'm thinking band pass filters only work on AC sources, not DC pulses you get from a rectified sound source..does that make sense? I'm hoping it works for you though! Keep us posted.


----------



## heresjohnny

I read about the circuit a little and I think there are a couple of things to try. One the capacitor and resistor between the input and the ground are used to latch on the rectified input signal, with a slow decay between the pulses coming off the diode. The circuit designer says that increasing the resistor will slow down the decay, this is one way to adjust how sensitive the signal to the motor is (maybe it needs a potentiometer here). Second is to ground the output through a capacitor before it goes to the motor, this should (fingers crossed) server as a low pass filter and reduce the noise going to the motor. I will try tonight!


----------



## heresjohnny

I have it working good now!

A 10uf capacitor from the motor input to ground got rid of most of the noise in the motor. I added some resistors to the potentiometer as described in the second circuit and the made it less sensitive to changes in the potentiometer. I was also able to connect the leads to the green LED eyes to the output of the comparator, and those worked also. Finally, I was able to connect the input to an amplified speaker and still got a good clean sound without affecting the circuit. All off a 4 pack of AA batteries.

The guy who made the original circuit drove 3 motors, an led and an amplified speaker all from a single input, so I am sure enough this will work to go ahead and order the parts to build a few. Anyone interested in a group buy, or maybe buying some 2 or 4 channel circuits? Hauntiholik, you still interested in driving your 4 skulls seperately? Dr. M?


----------



## heresjohnny

Well I jumped the gun on the fish circuit, it has not been very reliable for me, I think because it does not handle lower level inputs very well. I thought I would try the scary terry circuit next, it adds a pre-amp. I followed his directions and built up to the LED, and the circuit worked the first time. When I turn R6 up, the led flashes, then I turned it down until the LED just goes out. When I add the audio source, the LED flashes in time. I do not have to turn the source all the way up like I did on the fish circuit. I am wondering about why the LED flashes, anyone know? I am gonna ask around.

I had also drained my 6 volt battery pack down to 4.5 volts, so this may have caused the fish circuit to go bad. I will probably try it again.


----------



## strange1

I have several Gemmy skeleton head pairs and want them to say what I want them to.
This could be dangerous.

I tried the toy motor circuit and couldn't get it to work.

I took the talking fish circuit that heresjohnny posted, put it together, and it works.
(By the way, thank you Johnny for your input.)

I took the top circuit and added the amp to drive the speakers.
I left out the second circuit with the secondary motors.(u1b)
I also hooked the led eyes that were part of the origional skull to pin 1 of the lm324 and to ground.
I hooked all of this mess to a protable cd player and it works great.
The eyes flash with the mouth movement.
I can't say about the battery life, haven't had time to test that part of it yet.

Next I'm gonna try the other circuit Johnny posted.
But for right now, I'm satisfied with the fish circuit.


----------



## heresjohnny

Thats good news! I don't know what is happening to my attempts, the fish circuit and the Scarry Terry circuit do nothing but flash. Maybe my garage is haunted. I did find this online http://www.talkingelectronics.com/projects/OP-AMP/OP-AMP-1.html, and from this I can see that the first stage of the Scary Terry circuit is an inverting amp with a gain of 5 :googly:. Maybe my ghosts will leave and things will start working again tomorrow.


----------



## strange1

heresjohnny said:


> Thats good news! I don't know what is happening to my attempts, the fish circuit and the Scarry Terry circuit do nothing but flash. Maybe my garage is haunted. I did find this online http://www.talkingelectronics.com/projects/OP-AMP/OP-AMP-1.html, and from this I can see that the first stage of the Scary Terry circuit is an inverting amp with a gain of 5 :googly:. Maybe my ghosts will leave and things will start working again tomorrow.


I have also been wondering about ghosts around here.
When I first built the fish circuit without the amp stage it wouldn't work right.
I checked and rechecked the wiring a thousand times, made sure the values of the components were right and everything, and still it wouldn't work right.
I decided to walk off and leave it for the night, before I got my fine adjusting tool (HAMMER) out.

The next evening I tried it again, and it started working as soon as I put power to it.
It seemed to work even better when I wired up the LM386 to drive the speaker.

I have noticed this happening to other things I've put together over the years.
I just figured that since I do this kind of work in my basement that maybe there is some dampness down there that was affecting the circuits.
But now I'm not too sure.

I'm using 4 aa batteries to drive the thing, and I'll have to wait till I get the time to see how long the batteries will last.

As a side note:
I took some wavs I had on the computer and burned a cd to test the skull.
It is awful funny to see the skull talking with tweety birds voice coming from it.


----------



## heresjohnny

How much did you have to adjust the potentiometer on your circuit using the CD player? I had to turn mine all the way down, and I am beginning to think the CD player has a higher output level than an mp3 player. I managed to get 2 different fish circuits going on a single quad op amp (LEDs only), but the response was different for each one. When I tried to add a third everything started blinking, and it hasn't stopped since, even though I built a different circuit. Makes me think I have a bad capacitor or something. Oh, and I also am using 4 AA batteries.

I found a new 1458 op amp for the Scary Terry circuit, and an LM324 for the talking fish circuit locally, so I will try from scratch tonight after I check the other parts. I have been reading about op amps (see previous post for excellent link) and I think I understand how these things work now, so hopefully I scare those ghosts off now.



strange1 said:


> I have also been wondering about ghosts around here.
> When I first built the fish circuit without the amp stage it wouldn't work right.
> I checked and rechecked the wiring a thousand times, made sure the values of the components were right and everything, and still it wouldn't work right.
> I decided to walk off and leave it for the night, before I got my fine adjusting tool (HAMMER) out.
> 
> The next evening I tried it again, and it started working as soon as I put power to it.
> It seemed to work even better when I wired up the LM386 to drive the speaker.
> 
> I have noticed this happening to other things I've put together over the years.
> I just figured that since I do this kind of work in my basement that maybe there is some dampness down there that was affecting the circuits.
> But now I'm not too sure.
> 
> I'm using 4 aa batteries to drive the thing, and I'll have to wait till I get the time to see how long the batteries will last.
> 
> As a side note:
> I took some wavs I had on the computer and burned a cd to test the skull.
> It is awful funny to see the skull talking with tweety birds voice coming from it.


----------



## heresjohnny

Well I found my ghost. I built a new Scary Terry Audio Driver, and the damn LED flashed again. Checked everything, it still blinked. Before swearing off electronics forever I yanked the LED out and put it across the battery, and it still blinked. Just as I was about to throw the whole thing away I suddenly realized what was wrong. I was using a flashing LED.

So, the circuit works great with the LED. I am still trying to figure out how to get the skull hooked up to it without using the coil. The response and control of the Scary Terry circuit is much better than the fish circuit without the skull.

More to come.

Okay, so I had to go work on it some more. Figured out one way to hook up the skull using the TIP120 (not the coil), it almost bounced the skull off the work bench. I found that the closer you adjust R6 to where the LED just goes off, the more accurate the jaw movement is. And the jaw movement is very strong. I want to try a couple of more things and then I'll take a video this weekend.


----------



## heresjohnny

Here is a video of the modified scary terry circuit. I will be putting together a how to this weekend, more to come...
http://johnnyspage.com/video/talking%20skull1.wmv Toward the end of the video you will see how can adjust the gain down to get good jaw movement.


----------



## Abunai

heresjohnny said:


> Here is a video of the modified scary terry circuit. I will be putting together a how to this weekend, more to come...
> http://johnnyspage.com/video/talking%20skull1.wmv Toward the end of the video you will see how can adjust the gain down to get good jaw movement.


Very cool. Looking forward to the "how to."
I just picked up a "Mr. Clock Radio" today for $25 that I may try to hack.


----------



## Stiff Kitten

Yes very cool I cant wait for how to also


----------



## heresjohnny

Hey, I'm not gonna be able to get this how-to done. The circuit I demonstrated in the video is a very simple extension of the Scary Terry circuit. Connect a 22k resistor to the same pin on the IC that the diode is connected to. Connect the other end of the 22k to the base of a TIP120. Connect the emitter of the TIP120 to ground, and the Collector to the motor. Connect the other lead of the motor up to the positive voltage supply. You can replace the LED n the Scary Terry circuit with the leads that go to the LED eyes.

Good Luck!


----------



## strange1

As A follow up on the fish circuit.
I use the circuit in my Bucky skulls.

I have made 3 of these so far and each one works perfectly.
I have used a cd player and a mp3 player and both work equally well.

I used the circuit at the top of the page and wired the amp to it as in the second picture.

I didn't wire in the circuit that drives the 2 motors for the fishs body.
I didn't see any use for it on just a Bucky skull.
Although down the road, when I get the time, I'm thinking of using the second part of the Lm324 (U1 B) for eye movement.

I would post a movie of the skull working and talking, but I have as of yet figured out how to work my camera in that mode.


----------



## Stiff Kitten

Well I went to set up my skull so I could post a video of it. And of course it didn't work.So after checking everything 2 or 3 times to make sure it was all hooked up right, I opened up the skull to find the audio output transformer was fried.Since I had it open I could also look at why the eyes would'nt light up, they worked for the first night of the haunt. The leads that went to eyes were also fried. I also noticed that the thread that goes from the jaw to the motor is getting worn. I have another gemmy skull so I opened it up and it also is getting worn. I wanted everyone to know about the thread that is about to break. I am not sure what I am going to replace thread with yet; any ideas? I think before anyone puts these skulls in any prop you may want to replace thread or at least make sure you can take skull apart when it does break. Picture was best I could get. Hope you can make out what I am talking about.


----------



## Phil

I have only hacked one Gemmy, and it has worked reliably for three years. I am driving the motor and LEDs directly from one audio channel of a 12V car CD receiver (4 ohm stable) through a bridge rectifier. The other channel provides the actual audio output through a 4 ohm speaker. 
This configuration is an odd load and did not work with a home receiver (8 ohm) - popped it into protect. 
The only problem that I encountered was blowing the motor cap when I got froggy with the volume. This has not reoccurred after replacing with a higher voltage rated cap. 
With no one using this method I must be a genius or a fool (and so far my tipping the scale toward genius has been rare). Has anyone tried and abandoned this approach?


----------



## Dr Morbius

I've used a bridge rectifier for a toy motor to operate a mask jaw using a computer amp. I tried it on the Gemmy lantern using a boombox with no effect, but I needed to drive more than 1 prop so I didn't bother with it anymore, but yea, it's great cheap way to drive a prop from an audio source, provided the source is powerful enough.


----------



## Phil

Okay, so neither genius nor fool. I can live with that. 
It does require an amp with reasonable output power and low-impedance stability.


----------



## Abunai

Dr Morbius said:


> I've used a bridge rectifier for a toy motor to operate a mask jaw using a computer amp. I tried it on the Gemmy lantern using a boombox with no effect, but I needed to drive more than 1 prop so I didn't bother with it anymore, but yea, it's great cheap way to drive a prop from an audio source, provided the source is powerful enough.


So, I'm lost.

I have two of the Gemmy lanterns that I would like to hack.

I've seen several circuits posted on this thread by several people. 
What method did you finaly end up using, Doc?

Can you post a schematic and some photos of how the lantern needs to be modified to accept input from the circuit?


----------



## Dr Morbius

I used the schematic I put up in my first post of this thread, it's the only circuit I used during the whole hack.









Just make sure you use the stereo outputs of good amp, not line voltage or headphone jacks! Also use an ATX computer power supply using the 5V output from it...it needs a good amount of current to work, especially if you are going to use two lanterns.


----------



## DeathTouch

Looks like you just need a good transister and you are set. You can hook it up to any audio source then.


----------



## Sickie Ickie

instead of using the whole circuit, DT?


----------



## Sickie Ickie

Stiff Kitten said:


> ...I am not sure what I am going to replace thread with yet; any ideas? I think before anyone puts these skulls in any prop you may want to replace thread or at least make sure you can take skull apart when it does break. Picture was best I could get. Hope you can make out what I am talking about.


I can't really see in the pic, but try tiger wire to replace the thread. It's wire made for dolls, strong- but very flexible and thin like thread. Michaels or just about any craft store carries it.


----------



## Dr Morbius

DeathTouch said:


> Looks like you just need a good transister and you are set. You can hook it up to any audio source then.


One transistor won't work, you need the transformer to step up the stereo speaker voltage first.


----------



## DeathTouch

Dr Morbius said:


> One transistor won't work, you need the transformer to step up the stereo speaker voltage first.


Cant you just turn up the signal on the cd player that you are using or buy one of those cheap speaker amps?


----------



## Dr Morbius

The circuit already requires an amplified source to work, if you don't step up the voltage, you need to crank up the amplified sound to max, which sounds distorted and the jaw will just stay open or stay closed if you try to turn down the volume.


----------



## DeathTouch

How about using a push pull system. Since you have the mouth already working with a switch, couldn't you just remove the switch and add two transistor to form a push pull circuit. All you need is something to act as a switch. Wouldn't that work?


----------



## Dr Morbius

I dunno. Push ..er pull...I dunno.


----------



## DeathTouch

Acutally I don't even think you need that for what you are doing. I think one transister should do. You might need a reister on the base or emitter depends on what the other side of the transister is doing. But I think it should be too tough to just add a transister to have it take over for the switch.


----------



## Otaku

I must be missing something here; having not seen the circuit, it's hard to tell. I assume the skull uses a pre-recorded chip to supply the signal to the jaw motor, and this is what needs to be replaced with a different sound source. These "chips" usually look like small lumps of potting material on the board with various traces coming from them. Has anyone tried scraping the mask away from those traces and beeping them out to see what each one is doing? If this "chip" is the sound source, and it can be determined at what levels the outgoing signal is running at, is it possible to simply cut in the new sound source at that location(s)? Again, I'm making the assumption that the part of circuit that handles translating the sound into a signal that the jaw motor can understand is all downstream of the sound source.

I know I'm coming in way late in this hack, and this has probably already been explored (you guys don't miss much!) but that approach would have been my first plan.


----------



## Dr Morbius

That's the holy grail, Otaku, to cut into one of those chips and bypass it to use the onboard amp to play other sounds. 2 problems with that approach, at least as I see it,

1. If you are successful at bypassing the sound source and utilizing the onboard amp circuit, you're stuck with a crappy amp.

2. Even if you're happy with the crappy amp AND you are successful in bypassing the chip sound source, there's no gaurantee that by simply playing the new sound through it will activate the jaw. My experience is the blob covered chip handles both the sound AND jaw motor syncranization. Since that's the case, you need a seperate circuit to move the jaw motor anyways, so best not bother with the chip blob in the first place.


----------



## Otaku

Hmmm. I wish I had one of those boards to play with. Can anyone post a clear picture of the board showing the components? If there's a microcontroller on the board, then that's where the firmware code lives. That would be how the jaw is sync'd to the sound signal. I wonder if the Boris board could be duplicated and installed in the Gemmy skull? Those boards (as we already know) are hackable for external sound.


----------



## Dr Morbius

I'll take a pic of it later tonight...IF I still have it. I gutted the lantern to make room for wiring.


----------



## Terrormaster

heresjohnny said:


> Hey, I'm not gonna be able to get this how-to done. The circuit I demonstrated in the video is a very simple extension of the Scary Terry circuit. Connect a 22k resistor to the same pin on the IC that the diode is connected to. Connect the other end of the 22k to the base of a TIP120. Connect the emitter of the TIP120 to ground, and the Collector to the motor. Connect the other lead of the motor up to the positive voltage supply. You can replace the LED n the Scary Terry circuit with the leads that go to the LED eyes.
> 
> Good Luck!


HJ, I have the Gemmy Skull pair as well and am looking at using the preassembled Scary Terry board from Cowlacious. Do you think it work out-the-box or will I need to apply your changes to the board to make it work?

Also with the board can separate stereo left/right channels be used to drive each skull separately or would I need two boards?

-TM


----------



## heresjohnny

Terrormaster said:


> HJ, I have the Gemmy Skull pair as well and am looking at using the preassembled Scary Terry board from Cowlacious. Do you think it work out-the-box or will I need to apply your changes to the board to make it work?
> 
> Also with the board can separate stereo left/right channels be used to drive each skull separately or would I need two boards?
> 
> -TM


I am just now pulling together a parts list to see if I can finish this in the next few weeks. I have never seen the Cowlacous boards, but one thing to check is I think the board is for the servo driver, the circuit I was messing with http://www.scary-terry.com/audiodriver/audiodriver.htm is just the first stage of this servo driver circuit. If this is the case I don't think it will work because it is made for a servo, not a DC motor.

This first stage circuit does not provide enough current to drive the Gemmy skull, thats why I added the TIP120. I guess if you wanted you could try to tap into the cowalicius board at the right place with the 22k and TIP120. Alternately, I have seen a board you can buy that is made to drive the DC motor props like the Gemmy skulls, I'm not sure what it is called though.

Hope this helps


----------



## Dr Morbius

I think it's called Motormouth.


----------



## Otaku

Dr Morbius said:


> I think it's called Motormouth.


That's the one, but its not on the Hauntmaster Prods web site anymore. I think that Jim Kadel does have a how-to on the site for those who want to roll their own, though. Here's the link:

http://home.rica.net/jimk/projects/servo/index.htm

He writes that you feed your recorded sound into the board, but I don't see the audio input connections.


----------



## Terrormaster

Otaku, I believe that thats the same Toy Motor circuit that DM had been messing with and needs to be amped. It looks pretty straight forward though.

As for the Motor Mouth, here's the direct link: http://hauntmasterproducts.com/16.html which I found elsewhere.

HJ, where can I get the parts to build the Scary Terry circuit? I looked on Radio Shack's site and I couldn't find the MC1458 Dual OpAmp on there. They had some other OpAmps but I've been out of the electronics loop for so long I don't know if they're interchangable much. Man I remember RadioCrap carried everything - now they're like a mini over priced Best Buy.

Also, are you eliminating the K1 switch to the motor or does the collector from TIP120 to one of the pins on the relay?

-TM


----------



## heresjohnny

Terrormaster said:


> Otaku, I believe that thats the same Toy Motor circuit that DM had been messing with and needs to be amped. It looks pretty straight forward though.
> 
> As for the Motor Mouth, here's the direct link: http://hauntmasterproducts.com/16.html which I found elsewhere.
> 
> HJ, where can I get the parts to build the Scary Terry circuit? I looked on Radio Shack's site and I couldn't find the MC1458 Dual OpAmp on there. They had some other OpAmps but I've been out of the electronics loop for so long I don't know if they're interchangable much. Man I remember RadioCrap carried everything - now they're like a mini over priced Best Buy.
> 
> Also, are you eliminating the K1 switch to the motor or does the collector from TIP120 to one of the pins on the relay?
> 
> -TM


What I did was drop D2, the coil, and K1. I replaced the LED with the leads that go to the LED eyes in the skull. Then I add a 22k resistor from where DI, C2 and R8 are joined, and feed the other end of that to the base of the TIP120. Ground the emitter of the TIP120, and connect the jaw motor to the collector of the TIP120 and the positive supply. This was the circuit I used in the video I posted back on page 11 of this thread.

I get my parts from Jameco, I try to wait until I need several things and then do one order. The prices are so much cheaper then retail that you make up the shipping costs quickly. For example it cost $7 plus to get 2 1458's from the local supply house, and thats enough to cover the cost of the 1458's and the shipping from Jameco. Radio Shacks dual op amp is not compatible, it is made for a single rail supply, and the 1458 needs a dual rail supply.


----------



## heresjohnny

Here is the circuit I used in the video back on page 11.


----------



## Terrormaster

Thanks for the diagram HJ - thought I'd point one error, minor mind ya - you have two capacitors labeled C2.

Well put together my basic part list based on the diagram. It can be viewed here:

http://spreadsheets.google.com/ccc?key=plWgdv7gwBZvLApl6aP-2HQ&hl=en

Those are JameCo part#'s and prices. If you got a sec, take a look and let me know if I covered everything and got everything right (its been a long time since I did this myself).

-TM


----------



## Dr Morbius

Thanks for sourceing those, TM! I know what a pain in the butt that can be.


----------



## Terrormaster

Thanks... Wasn't easy and made a few guesses - been a long time since I've worked with this stuff. Had trouble remembering if the wattage for the resisters in this case mattered (went with 1/4 watt) or whether ceramic or electrolidic mattered for capacitors (if memory serves it's a matter of design preference not functionality). Either way gonna wait for HJ to verify the parts because if any of that matters I wanna duplicate what was successful for him (why reinvent the wheel right?).

Either way the cost is pretty effective as I could crank out 5 of these babies for less than what it cost for a two channel Motor Mouth. I only have the skull pair so all I need are two right now. One for my crone/witch stirring the cauldron and the other for her sister. Would love to get started in the next couple weeks.

-TM


----------



## Dr Morbius

Terrormaster said:


> Either way the cost is pretty effective as I could crank out 5 of these babies for less than what it cost for a two channel Motor Mouth.


That's the beauty of it. These kinds of things always get my juices going for prop possibilties.


----------



## heresjohnny

Okay, I checked the list and heres what I found:

1. The 1458 (jameco # 903429) is a surface mount, I would use 903509. The only reason I know to check this is I ordered surface mounts by mistake one time
2. I know the circuit shows a phono jack, but it is really one channel of a 3.5mm phono plug like 231176. My plan was to drive a pair of skulls off a single stereo input. I have a bunch of old 3.5 phono plugs lying around that I usually use, but I have ordered these before.
3. I use a linear taper 5k pot (29197), and a trim pot for the 1k like you already have selected.
4. If you are going to be making a lot of boards, you might consider picking up some boards from all electronics http://www.allelectronics.com/cgi-bin/category/455/Perf_Boards.html
5. I also used 189676, but these are optional, they are jst to connect the wires from the skull to.

The rest looks good!

Now, I was putting a parts list together, and I am planning on expanding the circuit some more, but I don't know if it will work or not. I was going to use part of the fish circuit:









and use another 1458 to add 2 more second stages. One will use R4 and C4 from the fish circuit to latch the output high, and I will try this to make the eyes glow steady while the skull is talking. The second one will use C5, R6, D6 and Q2 to have an output that will cause a motor to turn briefly each time the skull starts talking, this will be used to make the skull turn its head slightly each time it starts talking.


----------



## Terrormaster

Thanks Johnny,

Updated my price list to reflect the changes. Probably gonna put mine in an enclosure and make it a bit more modular. For example, I'm considering taking out the two 189676 connectors and just using a single 6P4C modular phone jack (151766). Then putting a similar jack on the skull side (or any other prop) and connecting it up with Cat3. That way the board isn't bound to any one particular prop (well without having to open the enclosure). 

-TM


----------



## heresjohnny

Cool! I look forward to seeing that.


----------



## Terrormaster

Question - I was thinking of adding an AC relay into the circuit that would effectively switch on/off power to an AC driven motor.

The idea is to use the audio to turn on/off a simple reindeer motor that drives the neck. Essentially as long as there isn't sound the neck doesn't move.

I haven't done any work with relays before so I'm not sure which kind of relay to get. I have a pretty good idea though where it would fit in the circuit. I'm pretty sure I'd isolate it with a diode and give it it's own trim to adjust the threshold.

-TM


----------



## heresjohnny

TM the original Scary Terry circuit drove a relay, maybe this will help http://www.scary-terry.com/audiodriver/audiodriver.htm

Put my parts order in today, got enough to try and get the additional modifications done.


----------



## Terrormaster

Yah, I saw that... Guess I would just put an appropriate DC Control/AC Load relay on it and it should work. Is it worth putting the amp from the Fish Circuit in or would I be better off splitting the signal and feeding the other end to amped speakers?

I'm almost ready to order the parts myself - I'm anxious to start tinkering. Right now I'm trying to decide if I should work on the skull hack or the armature for my cauldron witch first... 

-TM


----------



## heresjohnny

Terrormaster said:


> Yah, I saw that... Guess I would just put an appropriate DC Control/AC Load relay on it and it should work. Is it worth putting the amp from the Fish Circuit in or would I be better off splitting the signal and feeding the other end to amped speakers?
> 
> I'm almost ready to order the parts myself - I'm anxious to start tinkering. Right now I'm trying to decide if I should work on the skull hack or the armature for my cauldron witch first...
> 
> -TM


Are you thinking about the little amp for the audio channel? I thought of that myself, but I have a lot of powered computer speakers sitting around and I think the sound quality and available volume will be better using those. Don't know for sure though.


----------



## Terrormaster

heresjohnny said:


> Are you thinking about the little amp for the audio channel? I thought of that myself, but I have a lot of powered computer speakers sitting around and I think the sound quality and available volume will be better using those. Don't know for sure though.


Hmmm - true... I'll order the parts anyways and experiment on the breadboard... If it's worth doing I'll solder it down into the circuit.

-TM


----------



## Terrormaster

Johnny, you ever figure out how to latch the eyes to be on during the entire dialog? I haven't ordered my parts yet but after running through the circuit in my head (and Visio) I started thinking that the relay part I'm working on needs to behave the same way. Essentially I need to close the relay and latch it closed during the extent of the dialog. Then open it back up after a few seconds of silence.

I've looked at a few latching circuits and a couple Sample and Hold circuits as well. But just not sure how to do this.

-TM


----------



## heresjohnny

If you look at the fish circuit, he causes that action by using a capacitor and resistor on the input to latch it high. I was planning on having three outputs from my circuit: 1 that reacts to the voice to drive the jaw, one that latches high to keep the eyes on solid while talking, and one to twitch the head when the talking starts. The last 2 are based on the fish circuit. I can sketch up my idea and post it, but I have not tried it yet. I should be able to tell if it will work in about a week or so.


----------



## Terrormaster

A week is good for me - elected to work on the armature this weekend anyways and need to wait till next pay cycle before ordering parts. 

However, I like to tinker with the logic in the schematic - which stage in the fish circuit are you referring to - the one that drives the single servo or the one that drives the double servo? I'd assume you meant the double servo since I believe that controlled the body of the fish while the top single one controlled the mouth.

Thanks again for your help,
-TM


----------



## Terrormaster

Ok, gonna order the parts and try out this little plan I came up with. The 4066 is a Quad Analog/Digital Switch (same as the one Scary Terry uses in the Audio Servo driver). That should effectively keep the eyes on as long as there's a load on the control pin. I may drop a capacitor between pin 1 of the 4066 and R10 which should fade in and out the eye (am I correct?).

If I'm right this should do everything I've been talking about except controlling the ac outlet which I'm gonna ditch. Even then I should be able to just add a DC/AC relay on one of the 4 control ports of the 4066 to achieve that.










EDIT: Parts are on there way... I'll be experimenting with the above schematic on a breadboard so I'll keep everyone posted on my success or not.

-TM


----------



## Terrormaster

Half my parts are in, Jameco was really on the ball. Ordered the rest from All Electronics and they were a little slow getting the order out the door. I had actually placed my order with them a day before I placed the Jameco order. I still want to experiment with the 4066 switch so I grabbed one of those when I was shopping.

In the mean time I stumbled upon a nifty little freeware circuit board designer called DIY Layout Creator - it's a bit awkward to use, not very intuitive, and has a few memory issues so I have to save often. But heh, it was free so what more could I ask for.

Here's my design using the 4066 and based on the above schematic:










I'm open to suggestions and comments. DIY has an option to print out the traces only scaled to fit the board. While thats pretty neat, I don't own a laser printer nor do I have any PnP sheets to print to. Gonna just wire it right on on a regular PCB.

-TM


----------



## Sickie Ickie

Wow! Even I could mostly follow that picture!


----------



## Terrormaster

ARGH - After 5 hours yesterday I can't even get the Scary Terry circuit running on a damn breadboard. I've review the circuit over and over again and tested with a tester and still can't even get the LED to light on the breadboard (ok it lights if I apply voltage across it an it's resistor so I know that works).

Gonna tear it apart tonight and try again from bottom up. Any recommendations for unit testing where I can test it piece by piece as I build?

-TM


----------



## Terrormaster

*Breadboard Layout*

Ok, this is the layout I'm gonna use on the breadboard tonight. This incorporates HeresJohnny's Gemmy version of the Scary Terry Audio Driver circuit. Can someone let me know if I've matched it up to the schematic right.










Thanks,
TM


----------



## Terrormaster

That did the trick. Added the 4066 in to experiment. Feeding the input from the diode D1 directly in to pin 14 of the 4066, pin 1 goes out to another 470 resistor and then to the LED. Doesn't latch though. Instead of pulsing brightness based on the sound it just flashes brightly on/off.

Johnny, any luck with the latching with the capacitors?

Here's how it's lookin so far:






-TM


----------



## Abunai

Finally!

It took me all year, researching and studying electronics between working on MANY other props, but I got this to work. 

Thanks to HJ, TerrorMaster, Dr. M, and others for all they have posted to this thread.

The circuit that finally worked was the one that HJ demonstrated on page 11 of this thread, and then posted a schematic for on page 14. 

I tried to breadboard the circuit, then tried it on a perf board (as diagramed by TerrorMaster) but had no luck. 

I eventually found a shareware demo of a program called "DipTrace." This program is phenomenal. It allowed me to draw the schematic, then convert the schematic into a PCB layout with auto-placement of the components and auto routing of the copper traces. I then printed out the traces to a trasparency, burned the pattern to photosensitive PCB board, developed, and etched out a very professional looking PCB board. 

I highly recommend the "DipTrace" program to any electronics enthusiasts...the demo version allows creation of PCB boards with up to 250 contacts (this project used 35 contacts or so.) There is a good deal of learning-curve involved, but it is well worth it.

I can't attach them here, but if anyone is interested, PM me with your email address and I will send you the schematic file and the PCB file that I created for this project with DipTrace.


----------



## lele

Abunai said:


> Finally!
> 
> It took me all year, researching and studying electronics between working on MANY other props, but I got this to work.
> 
> Thanks to HJ, TerrorMaster, Dr. M, and others for all they have posted to this thread.
> 
> The circuit that finally worked was the one that HJ demonstrated on page 11 of this thread, and then posted a schematic for on page 14.
> 
> I tried to breadboard the circuit, then tried it on a perf board (as diagramed by TerrorMaster) but had no luck.
> 
> I eventually found a shareware demo of a program called "DipTrace." This program is phenomenal. It allowed me to draw the schematic, then convert the schematic into a PCB layout with auto-placement of the components and auto routing of the copper traces. I then printed out the traces to a trasparency, burned the pattern to photosensitive PCB board, developed, and etched out a very professional looking PCB board.
> 
> I highly recommend the "DipTrace" program to any electronics enthusiasts...the demo version allows creation of PCB boards with up to 250 contacts (this project used 35 contacts or so.) There is a good deal of learning-curve involved, but it is well worth it.
> 
> I can't attach them here, but if anyone is interested, PM me with your email address and I will send you the schematic file and the PCB file that I created for this project with DipTrace.


do you still have the schematic file?


----------



## Terrormaster

Abunai, thanks for the shout out. I need to pull those schem's though as they were old designs and didn't work quite right.

Hey maybe you can do a tutorial on DipTrace? I had nothing but absolute headaches with it. How do you do 3-pin and 4-pin headers? Everytime I did anything like that it would always drop of the trace when I converted it. Also deleting individual connections in the trace app was a nightmare.

The ONLY thing I like about it the auto-layout that finds the best traces.

For now I'm sticking with DiY as it gets the job done.


----------



## berzerkmonkey

So... I'm an electronics know-nothing, and am really confused regarding this thread. How does this actually work? Are all of the electronics in the skull bypassed with this board tht I saw a few pages back? Or am I not getting the point here? (Probably the latter.)

Say I have a few Gemmy skulls lying around (and I do.) How would I start to tackle this project?


----------



## scruffy57

*how to*

I am curious also. I just purchased to gemmy talking skulls from Lowes for $12 each. I would like to hack them. I am no engineer, but I can follow directions. Is there a how to somewhere using mp3 player as audio source?

Thanks


----------



## Dr Morbius

No how-to really, this thread was just a discussion regarding the various circuits we used to hack talking Gemmy stuff. Pick one and try it out, the schematics should be here as far as I know. All the circuits replace the Gemmy circuits and rely on an audio source to make the jaw move.


----------



## RandalB

Has anyone tried using a color organ type curcuit to power the 5V wallwart? I think that if you connected the Wires for the Motors and LED's to the walwart and then ran an MP3 Player into the color organ curcuit you should get a similar effect; IE Mouth moving and LED's flashing in time to the sound track. 

I am in the process of doing something similar to a Gemmy Dancing Santa (Has the Movement and Input Jacks, outputs 6V to the head for mouth movement) and I am thinking of Driving the Skull with the head output. I'll keep everyone posted with the results...

RandalB


----------



## RandalB

RandalB said:


> Has anyone tried using a color organ type curcuit to power the 5V wallwart? I think that if you connected the Wires for the Motors and LED's to the walwart and then ran an MP3 Player into the color organ curcuit you should get a similar effect; IE Mouth moving and LED's flashing in time to the sound track.
> 
> I am in the process of doing something similar to a Gemmy Dancing Santa (Has the Movement and Input Jacks, outputs 6V to the head for mouth movement) and I am thinking of Driving the Skull with the head output. I'll keep everyone posted with the results...
> 
> RandalB


It works, +5 V to the motor leads makes the Mouth open/close so the light organ circuit pulses the wallwart with good aproximation. Can't do the eye motor yet, requires voltage polarity reversal and I doubt I'll have time to fix that this year (A reverse wired wallwart to a separate organ circuit?). The LED's need to be repaired (I broke their + lead while taking it apart...Gemmy doesn't take much time to inspect solder connections I guess...) but I'm sure I can get those working as well.

Best news: The Big Mouth Bass has the same guts... LOL

RandalB


----------



## RandalB

Further update: Hacked the Gemmy Dancing Santa and the controls from that will operate the skull with no problem. The AUX in allows the Skull's mouth and LED eyes to function to an MP3 Player. It's also amusing to watch it sing christmas carols... I was going to dress the body back up as Santa Skull but the wife had a fit.. LOL

The Light organ to 5V wall wart also works well but the Skull will open and close his jaw to various parts of the music, not just the spoken words. A voice track however, works perfectly. 

RandalB


----------

