# SSC-32 and VSA servo problem on ch8-15



## Grimsby (Sep 11, 2007)

Hello
I have an SSC-32 connected to a PC running VSA. I have built a few 3-axis skulls using the Hitec 425BB servos. The SSC-32 has 9VDC for logic power, and a separate 5VDC 20A supply for the servo power.
Everything works for controlling the servos using channels 0-7, and 16-23. 
BUT - when I use ch8-15 and ch24 and up, the servo attached to that output develops a chatter.
I am running VSA 4.0 and the SSC-32 is from 2007.
I am wondering if a firmware update for the SSC-32 will resolve this? I seem to vaguely recall someone else having this issue way back when.
Thanks in adavance


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## HomeyDaClown (Oct 3, 2009)

I've used several SSC-32s and the only time I've experienced chatter is when there was a power issue (voltage drop). At first it appears as though certain channels are not working properly.

I would disconnect servos from the working channels and see if the problem persists. You can get a voltage drop if the servo power leads have been extended and the wire is not a heavy enough gauge as well. 

You might want to monitor the servo supply voltage with a meter as several servos are running. It doesn't take much to drop below 4.8 volts from 5 (the minimum operating voltage for most servos).


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## Grimsby (Sep 11, 2007)

I moved the servos (all 16) to the ch0-7 and ch15-23. It works perfectly, and the voltage stays at 5.02. Very odd. So I put the LED eyes on the other channels. It's functional for Halloween. 
I disconnected the ch0-5 servos, and ran ch6-8. Naturally ch8 gave me problems still. Again, very odd. I will keep researching. 
Thanks again for the advice!!


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## lostskeleton (Aug 30, 2011)

http://www.lynxmotion.com/s-4-electronics-guides.aspx#serv

Lynxmotion makes some terminal programs that might come in handy for troubleshooting this. If your power supply is what you say it is and the jumpers are set correctly you should be in the clear. Make sure the 9 and 5V are isolated in the jumper settings as well as the voltage is shared between all the servos. HomeyDaClown is right in thinking about the voltage drop and wire size, if possible you should check the voltage at the servo to verify that you are at 5V and not below 4.8 as that is the miniumum those servos are rated for and could also effect the current available to the servo Other than that, I couldn't find anything in the manual that would make me think anything else could be wrong.

Keep us up to date if you figure it out or have more questions, I have one of these at home and could fool around with it to test a few things out.


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