Prototrak Plus Retrofit with Mesa 7i77 & 5i25 cards

Many apology. My intent 1.6v.

For pic of drive look at link or try paste:

forum.linuxcnc.org/media/kunena/attachme...712/IMG_0742_1-2.JPG

MagneTek
Motor drive p/n 15028R
p/n22241000
model: 4020D-143

many thanks!!
Motor Data Sheet

No, that is the motor, and it has nothing to do with the drive other than it is powered by it.
You should be applying your test voltage between two of the terminals on control input of the amp (With regard to servos that are more complex than a simple amp often called the "drive" because it is what drives the motor.)
Here in the old thread you took a picture of the terminal in question.
forum.linuxcnc.org/media/kunena/attachme...21712/IMG_0813_1.JPG
In that picture either the red and green wires, the red and white, or the white and green is the pair you need to apply the test voltage to. You need to test to see what does what.
You will also have to have the two terminals that were connected with the black jumper wire connected by a jumper to enable the amp (drive).

My many thanks go out to: Todd Zuercher, andypugh, tommylight, PCW, lakeweb and bevins for your invaluable advise, unwavering support, humor, honesty and it is with great regret there has been a most regrettable error on my behalf and I have managed to goof up the "x" axes of the amplifier. Todd the pic you referenced is correct as to my method with exception a meter was placed where the variable power supply gator clip-on leads came together with a length of the gray with red plug. No smoke, I think it is very likely when I turning off variable power supply with protrak amp connected.
I have no change in the lights on the protrak amp as to to indicate any error, but cannot get the servo to move at the same value (in the 1.4 to 1.5v range) from "x" & "y" currently, only the "y" axis will move. I have looked at plug interface to cabinet, swapped out center (see link the big blue cylinder in the center) capacitor with its psb, checked the fuses. I did not want to wait any longer to get this out. I would truly like to thank each of you for your time. I will be looking for another ebay I fear. If there is something I am missing?

forum.linuxcnc.org/media/kunena/attachme...21712/IMG_0816_1.JPG

Many, many thanks to all!
Thanks to the forum!

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configurationI don't remember if you said what parts you replaced after your first accident with miss-wiring the transformer.
Did you replace, or repair one or both of the servo amps? Which one? Did you have to spend a lot to find a replacement?

It may be advisable to just cut your losses with these old amps that are undocumented, rare, and probably difficult and expensive to replace, And get something that is common, well documented and easy to use. Something like these.

or

and a simple power supply should work for you.

Hopefully if someone has a better idea for a better amp replacement they will chime in.

Many thanks Todd! Could not find anybody to fix or repair, I purchased "used as where is" and it was high $ enough, from ebay. If you thought the components you describe would work with my servo and power supply I would give it a try.

many thanks!

Absolutely, if your amp is fried, Todd's suggestion is the way to go. I found a few sales of your amp, all were in the $1000 range. And read Todd's list, these things are undocumented. The second link won't work for you, it was for a brushless motor. You want a brushed servo driver. Those Advanced amps are a dime a dozen used. So if you goof one up, it won't cost you like that Prototrak.

If you decide to dump the Prototrak, you will get help here with the power supply you need. Chinese power supplies run less than ten cents a watt. I used them to get a friend's off grid charging going. Link to Off Grid Charging

You won't have to modify the supplies, This was a special case for battery charging. It is that the price point is so attractive.

And everything will be clearly documented. You will get explicit help on how to hook these things up.

Best, Dan.