What's the DC voltage measured from gate to source for the two output transistors in that channel?
if its 10ohm r150 r152 r250 r252 they are all 9.9ohm
already measure those on page one, so theyre not gate resistors i think. then i dont know what theyre on board.
already measure those on page one, so theyre not gate resistors i think. then i dont know what theyre on board.
Things change.
Did you check the driver transistors for leakage, open junctions as well as shorted junctions?
Did you check the driver transistors for leakage, open junctions as well as shorted junctions?
Remove the two gate resistors for the two installed output transistors and measure the g-d resistance and the g-s resistance for each transistor and post the values.
Do NOT apply power with the gate resistors out of the circuit.
Do NOT apply power with the gate resistors out of the circuit.
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What could have happened to the good channel if all you did was to replace the FETs?
Do you have the originals that you could solder back in (no need to solder to the MEHSA strip to see if anything changed?
Do you have the originals that you could solder back in (no need to solder to the MEHSA strip to see if anything changed?
well, legs are cut. im not good at trying to take it out when theres three thick legs on board.
yeah, only done is outputs changed and q210 q110 pushed close to heatsink with paste
yeah, only done is outputs changed and q210 q110 pushed close to heatsink with paste
In the future, heat the MEHSA strip from behind and lift the transistor and stand it straight up. Then apply new solder to all 3 legs so that you can lay the tip of your iron across all 3 legs (heating all at once). The transistor will generally fall out of the board.
Do you have positive and negative rail voltage?
Do you have positive and negative regulated voltage on the power supply pins of the op-amps?
Do you have positive and negative rail voltage?
Do you have positive and negative regulated voltage on the power supply pins of the op-amps?
i dont have that wide iron to get them out. post #29 there was both voltages. and left channel seems ok.
these voltages?
these voltages?
Just the rail voltages and the voltage on the power supply pins.
You lay the iron down so the length of the tip is in contact with the pins.
You lay the iron down so the length of the tip is in contact with the pins.
I don't understand your question.
Measure the DC voltage on the power supply pins of the op-amps.
Measure the DC voltage on the power supply pins of the op-amps.
With no power applied and nothing connected to the speaker terminals, what's the resistance across each pair of speaker terminals?
right channel is 17.8V and left 37V measured from here.
speaker terminals 4.8-4.9kohm
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What's the DC voltage on pin 14 of the LM339 in the power supply about 5 seconds after remote is applied?