Hi everybody. Im working on my AL5A arm and gotten to the point of testing the servos on Lynxterm. They all work according to the instructions except for the shoulder servo (HS 755HB). When I click on channel 02 of Lynxterm the shoulder slowly falls forward like its losing power and then does not respond to the sliding bar for me to make adjustments to move it back. When I click on ALL=1500 my arm is not at 90 degrees, closer to 45 degrees because of the shoulder servo. I have taken out the shoulder servo and tested it with Lynxterm without the arm and it responds fine with the sliding bar, servo horn moving back and forth. I hit ALL=1500 for the shoulder and reinstalled it, but once again when I tested it with the arm it does the same thing of slowly moving forward and does not respond to the sliding bar. Looking at the instructions can it be that the mechanical dampners are too lose? I know there was a caution of not to over tighten to avoid overheating of the servo. It seems like the servo is not able to maintain the weight of the rest of the arm. Does anybody have ideas/suggestions of what might be causing this or a test I can do to see whats up.
Appreciate any help.
Your words are fine, but an image or two would help. Also this link is helpful. viewtopic.php?f=32&t=6286
I am thinking you may have a jumper in the wrong place or a power supply not connected. 
Can you post some images of the wiring on the SSC-32?
A weak servo under load may indicate a weak power supply. What is your power supply?
The two pics that Im sending is the SSC-32 set up for Lynxterm. I know that the 6v wall pack is not plugged in, but I did use it during the servo test lol. The servos are plugged into the proper channels with the black wire on the outside and the green power light is on. I looked over the Servo Mid Position Tutorial and have a couple of questions about power. When you are referring about power is it the 9v that is applied for Lynxterm or the 6.0-7.2v? I used the 9v and was wondering if this is causing the shoulder servo problem? Also under Connecting Power I noticed that I have to install a jumper to VS=VL which I did not (refer to pic). Under SSC-32 it says “To allow custom servo positioning on powerup, the servo controller does not automatically generate pulses. Apply 6-7.2vdc to the VS1 terminal and install the following jumpers: VS=VL, VS1=VS2, Both baud for 115.2k, TX and RX to enable DB9 port.” Im a little confused about baud for 115.2k, TX and RX to enable DB9 port. Is this something that I adjust on Lynxterm or my laptop? I hope the pics help. Zoomkat and Robot Dude what do you mean by weak power supply and can I figure it out using a volt meter or portable digital mutimeter? Is this where to move the servo’s output shaft to its mid position, the servo needs to receive 1.5mS, positive-going pulses every 20mS.
Thanks.
So nothing is changed except to install the servo into the brackets? This makes no sense.
Leave the arm assembled.
Remove the VS1=VL jumper.
Power the VL with a fresh 9vdc battery.
Plug in the wall adapter.
Run Lynxterm and select the shoulder servo and move the slider.
What happens?..
Sorry for the misunderstanding… I did reinstall the servo back into the C brackets of the arm and it continued to do the same thing. Now… I doubled checked my work and the VS1=VL jumper is removed, have a new battery, and plugged in wall adapter with success of green light on circuit board. So it looks exactly the same as my pics. I am still having problems with the shoulder servo. Before it would slowly fall forward and would not respond to the slider bar to move it back. Now I have to first physical put it in a 90 degree angle, but only able to control it going forward not backward. When I hit ALL=1500 its at a 45 degree angle and I am still able to control forward but not backwards to lift the arm up. All the other servos work fine. I hope this makes sense. Any suggestions?
It sounds like the servo amp has lost a bank. In other words the motor controller inside the servo has one half of the output stage blown. We will replace the servo if you can provide an invoice number. You can email us for more help.
Ok I still have the invoice that was emailed to me that has the Order Number. Im going to forward it to support email. If it needs to go somewhere else please let me know.
Thanks.