We did more detailed test to the board last week.

Since last week when we powered up the board with NIM rack, it heated up very soon and had some bad smell. Just in case the NIM rack we have doesn't give the right power and may cause some damage, this time we powered up the board with external power supply. The first problem we found out, it is the 8V power supply of this board which give power to drive the galvo, has a much large current than it is supposed to be, that is also the reason why they board heat up so soon we guess.

At the beginning, we just powered up the 20V part of the circuit, and sent a sine wave instead of the quadrant signal to A,B,C,D port one by one. By checking each check-point inside the board, we could see clear sine wave. 

Then we powered up also the 8V part, the signal at the check-point started to have high frequency oscillation in MHz range. We traced it back, found out the oscillation was already there since the beginning of this path.  

When we wanted to do more investigation of the problem, we were looking for some checking point on the board according to the design, but we could not find them. So we checked the date written on the board, it has been done in Aug 1999, but the design was finshed later than that, so we guess there may be newer version of this board in TAMA and they could have better performance than the one we have in Nikhef now.