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Elvis Kabong
 
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"boardjunkie" wrote in
message
oups.com...
You have mail.


In case anyone else was following this and may
need to know, the following is what I sent to
Travis:

A brown wire goes to one of the AC leads of the
bridge rectifier to the anode of the diode
on the far right bottom corner of the left channel
PCB (the module toward the front of the amp).

Another brown wire goes from that same PCB at a
junction of a 2.7K 1 watt resistor and a
..1mfd 250 volt cap next to that above mentioned
diode on the right bottom corner to the
right channel's PCB 2.7K .1mfd junction similar
location.

On the schematic, the brown wire goes from and is
labeled going from AC bridge terminal
to D7's anode. However, not indicated on the
schematic, but on my notes, the other brown
wire goes to both channels' Q14 collector, C17,R7
and R8's junction - from one channel
to the other.


This is the SWR bias method as follows:
1KHz on signal generator
2 ohm load - one channel at a time
Signal in to Mono Return
Master pot full CW
Effects pot full CW
Bias trimmers full CCW
Variac set to 115VAC RMS
Signal generator output full CCW
Amp on Stereo mode

Raise signal to get 2 volts RMS at output of amp

Set Sweep to 50 µ seconds
Set Volts/Div to .2 volts

Position waveform to find tiny notch in waveform,
turn trimmer CW until notch removed. Same
procedure
for each channel.


Hope this helps,
Good luck,

Ed @ Sonic Surgery