Perry when I scope the output for the low side if I put the probe ground to the source leg the amp goes in protect as soon as I touch the ground to the source leg.
That's why the low side was grounded the amps Ground Terminal that's the only way I could read the low-side waveforms.
I'll get back to you with the answers for the other questions ASAP
That's why the low side was grounded the amps Ground Terminal that's the only way I could read the low-side waveforms.
I'll get back to you with the answers for the other questions ASAP
What's the resistance from the B+ terminal to the positive and negative speaker terminals (disconnect B+ to measure)?
From B+ to speaker + it started at 5.98 megaohms and just kept climbing ever so slowly.
From B+ to speaker - it started at 7.05 megaohms and just kept climbing ever so slowly as well.
From B+ to speaker - it started at 7.05 megaohms and just kept climbing ever so slowly as well.
I'd like to determine why you have DC on the low-side drive.
Are all of the rail caps completely discharged?
Are all of the rail caps completely discharged?
The rail caps are not on the amp.
if I put the rail caps, output fets or rectifiers in the amp. The amp goes in protect so they are all out of circuit.
if I put the rail caps, output fets or rectifiers in the amp. The amp goes in protect so they are all out of circuit.
What's the DC Voltage (black probe on the main ground) on the low-side source leg of the outputs.
Okay black probe on Main ground Red probe on the low side Source pads I get a measurement of 10v then it drops to 9.79v then back to 10v.
It repeats that bouncing voltage.
It repeats that bouncing voltage.
Black probe, same place, what is the DC voltage on the secondary center-tap?
Solder a rail cap on the negative rail (connection can be made with small jumper wires), what pin of the 494 is driving the amp into protect?
Solder a rail cap on the negative rail (connection can be made with small jumper wires), what pin of the 494 is driving the amp into protect?
Okay black Probe on Main ground Red probe on center tap I get. 0.001
On the tl494 it looks like pin 16 is causing protect it's reads. 12.11
On the tl494 it looks like pin 16 is causing protect it's reads. 12.11
Ok both waveforms are in .5v 5us probe x10 pics below.
Ground reference source pad for high and low side.
Ground reference source pad for high and low side.
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