I'm looking for some help on a Belles 450 using J50 K135 combo.
40mv DC left channel
115F output temp
140mv DC right channel
130F output temp
Added Temps because it was not running hot at all.
Never played thru speakers yet as I wanted to check bias and try and reduce DC at outputs.
Can't find a trim pot to adjust.
Can't find info on the amp anywhere except a schematic of one channel which I can post as well as internal pics if this would be a proper place to do so.
Thanks
Mark in GA
40mv DC left channel
115F output temp
140mv DC right channel
130F output temp
Added Temps because it was not running hot at all.
Never played thru speakers yet as I wanted to check bias and try and reduce DC at outputs.
Can't find a trim pot to adjust.
Can't find info on the amp anywhere except a schematic of one channel which I can post as well as internal pics if this would be a proper place to do so.
Thanks
Mark in GA
Those pics should cover the board from input to output.
The 2 threaded holes in the middle of the board are direct to speaker binding posts.
Looks like the schematic shows 100ohm variable resistor in the middle of schematic? Am I correct?
If so I can't find it.
The 2 threaded holes in the middle of the board are direct to speaker binding posts.
Looks like the schematic shows 100ohm variable resistor in the middle of schematic? Am I correct?
If so I can't find it.
Huggy,
Do I have to desolder and remove the T03's to check good or bad, or can I check them on the board?
Do I have to desolder and remove the T03's to check good or bad, or can I check them on the board?
In the picture in post #5 the two resistors that form a "V" are the degeneration resistors for the upper(+) differential pair. The two resistors side by side of the same value below the "V" pair are the degeneration resistors for the lower(-) diff pair. The schematic shows those two resistors as a trimmer, that should be for DC offset. Should be simple to pull resistors and install a trimmer.
Craig
Craig
