I found this in my files that I had copied from another post back in the day.
SX 828 Bias & Offset Procedure
The bias measuring points for the left channel are pins # 11 (neg lead) and pin # 17 (pos
lead).
The bias measuring points for the right channel are pins # 12 (neg lead) and pin # 18 (pos
lead).
On page 43 IN the scan and page 49 OF the .PDF is the drawing of that board.
this is on page 46 of the downloadable sx-828 .pdf in the database...
Both sets of pins are on the more pin populated long edge of the board, one wire on each
pin goes to the transistors and the other wire goes to the protection board.
Through a long involved search, my best guess (98% reliable) is to set the bias at edit 20
millivolts (0.020 V).
The Pioneer procedures recommend using 8 ohm dummy loads, BUT THEY are talking
about units that have been checked out at the factory!! Not something at initial powerup
after extensive work, ESPECIALLY around the bias section...
The first setup pass for (most importantly ) offset should be done with NO LOAD, as IF
there are HIGH VOLTAGES, there should be no (or little chance of) damage, as
damaging levels of current cannot flow through a missing load.
The OFFSET target voltage is zero volts with NO SIGNAL. 0.000v
You probably won't get it, but the minimum voltage you DO get will tell us of the state of
health of the amp (as discussed in this thread)
Offset voltages can be measured on pin 7 and ground for the left channel and pin 8 and
ground for the right channel. These pins are on the opposite side of the board, at the
corners.
OK, through past experience the bias setting is about 18 to 20 millivolts.
The pots closer to the middle of the board across the long axis are the offset pots.
The pots closer to the outside edges of the board across the long axis are the bias pots.
For anyone who encounters this problem in the future in order to get bright
