MBQuart PAB 1200.1D

[mon5t1]

With ground reference on the base of Q1A Pin8 -8.955V Pin 9 -8.955V with reference on Driver Board Ground Pin8 0.66mV Pin 9 0.00V

I also saw the pulled vias, it happened during the second desoldering of the driver Board, except for 4 connections all traces are on the other side of the board, of course I checked and repaired them. The 4 connections on the top side I repaired with short cables.

After repairing the power supply, the error pattern was exactly as it is now. Since I had not yet unsoldered the driver card so I do not assume that it is due to the pulled vias

 

[Perry Babin]

ChipQuik will prevent any via damage (when used correctly).

At this point, I don't have any more suggestions. If/when I have anything else, I'll post.

 

[mon5t1]

I use AMTECH NC559 normally I have no problems with the vias but this board seems to be very sensitive.

Thanks for your help Perry 👍

 

[mon5t1]

i have just decided to remove the two output inductors and remove the bridge between G-S of Q1A. The amp turns on normally without drive but as soon as I inject a signal the driver ic starts but only as long as I inject a signal.

Measured at the high/low site gate resistor and at the drain of the output fets

 

[Perry Babin]

Is the drive the same as the input frequency or at the normal operating frequency (100kHz, approximately)?

If you install only one inductor at a time, will it power up with either inductor in the circuit?

 

[mon5t1]

I forgot to write that the drive has the same frequency as the input frequency.

I will test tomorrow if the amplifier starts with one of the inductors in the circuit at a time

 

[mon5t1]

If only one of the two inductors is in the circuit, the amp turns on but without drive. With both in the circuit it is of course the same, drive is there but the amp draws a lot of current.