Rockford Fosgate Punch 800.2

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I removed the jumper from the bias transistor and followed its traces through the board and one of them went to Q309 and from there to Q310.

I removed Q309 and Q310 from the circuit and the amp idles fine with no pulsing but does not produce clean audio.

I will try and put new Q309 and Q310 in the board to see if it helps.
 
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That should be OK.

Jump the transistor shown in the image below. Remove all jumpers from the 300 series channel and have all components installed in the 300 series channel.

Power the amp up through a current limiter. It will pull significant current initially but the current should drop off. Does the current drop to what you'd expect for this amp?

If so, does the 300 series channel work properly?
 

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That should be OK.

Jump the transistor shown in the image below. Remove all jumpers from the 300 series channel and have all components installed in the 300 series channel.

Power the amp up through a current limiter. It will pull significant current initially but the current should drop off. Does the current drop to what you'd expect for this amp?

If so, does the 300 series channel work properly?

I jumped the transistor, and powered up through 2 20 watt 8 ohm resistors for a 4 ohm 40 watt limiter.

The amp powers up and didnt draw any current, it produces sound through that channel but is distorted.

If I remove the limiter and power up it draws 40 amps current and chatters.
 
See if it powers up and produces audio with the 2 ohm resistor, if not we'll have to go at this a bit differently. Reinstall the jumper on the bias transistor for the 300 series channel and re-check to confirm that the amp will produce clean audio from that channel.

A couple of questions:

1: Leave the jumper wire on the transistor Q11 marked 2A?

2: Power the amp up with the 2 ohm 80 watt resistor in line with B+?

3: Check for audio without the jumper on the bias transistor first, then install the jumper again and re-check audio?

I checked for audio a few posts back with the 2 ohm resistor inline with B+ and it produces audio but very distorted.

I just want to be sure we are on the same page here.

Thanks Perry.
 
Before we get started again I found something I thought I would bring up.

I removed all jumpers.

I removed Q10 marked 1A the amp powers up fine and idles and produces audio but wont clip turns into the shark fin waveform eventually. The waveform is clean until that point that it does not clip. The outputs do not get hot either.

What is the purpose of Q10?

Is this important or do I re-install it and proceed with what you asked?
 
OK all 3 jumpers installed, no current limiter just straight to the supply.

100Hz wave scope set to 2ms/20vd

1st pic is 3 series channel we have been working on clean audio, no heating fets, no current draw, idle is stable.

2nd pic is of the defective channel I originally posted that was all burned up, clean up until clipping, no heating fets, no current draw, stable idle. I am sure this channel has some defective components because of the burned source resistors, but one channel at a time and to figure out why this amp cant enable the outputs without the jumpers would be the most important.

Thoughts?
 
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