Help driving GSI 120DT Galvo motors

[thorson14]

Hi Steve,

I have a candidate for helping with the desoldering and lifting of the component of interest. He works in a fabrication lab and teaches one of the biggest engineering courses in our school building gyrocopters from scratch.

He had a couple of questions, which also echo some thoughts I was having:

1. What is the specific component that requires lifting?
2. Can this component be sacrificed? Can the component simply be cut off thereby exposing the necessary leads? I assume this would be okay IF we knew it was indeed the right connection. In the case that it isn't, could the component be replaced after its removal?
3. What is suggested procedure or what specific tests are you thinking of?

He wants me to find this information out and report it back to him. I think he will help us, he is just hesitant about having to desolder a component with too many pins on a multi-layered, through-hole board.


Thank you,
Todd

[mixedgas]

You don't need just a de-soldering person. You need a person with enough analog electronics skills to listen to me on the phone, and to look at schematics fragments in order to select the component I want de-soldered. We don't know what that is yet. You need a EE or ET on your end who understands OP-Amps and Analog Circuitry. . We (meaning He or She, and I) need to map out the board and select the injection point. Otherwise it needs to come here. This is not that simple, because it is a multilayer board. I can scan in fragments of similar circuits, and they and I can make an educated decision on what to clip/remove and where to inject the signal, and at what voltage level.

!
The LT parts are dual opamps. One op-amp in each LT part converts the current mode signal from the DAC chip to a voltage. The other will add a level shift and/or gain to that signal. We need to locate the second circuit and determine if it is a summing or non-inverting amplifier, locate it's inputs and outputs, input and feedback resistors, and act accordingly. Otherwise it needs to come here.
!

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Did your PI have any luck getting the schematic?

Steve

[thorson14]

Hi Steve,

Thank you for the reply. I have a meeting shortly to discuss this situation. At this point, I don't think he has been able to get that schematic but I will find this out in the meeting.

I have contacted the senior electrical engineering technician among others with the expertise to help but those that I have gotten a response from seem to have little time for me.

I think it is going to be best to send you the board for testing directly. I know my PI was on board with this last week, so there should be little change there. I will confirm shortly.


thank you,
Todd

[thorson14]

Hi Steve,

I would like to send you the board for testing. Do you want to email me directly information of where to send it? Or how would you like to proceed? I will arrange to have a return shipping label sent to you via email as well. If you are able, could you send me a unofficial quote on what you estimate you will charge?

No schematic to send over yet - I will continue to try to track this down.


Thank you,
Todd