Hello all.
Okay, I've been lucky with trial, and error troubleshooting, and eventually repairing circuits. Don't want to waste anyone's time here with stuff I should already know. But I just can't figure this one out.
Getting weirdness from bridge mode.
First thing I did was replace the open 27K feedback resistor that had failed open.
In bridge mode, I'm getting a larger signal on negative side (inverted right channel) than I'm getting from the positive side (non-inverted left channel).
Both right, and left channels are putting out the correct wattage in stereo mode.
Bridge switch seems fine. The R channel input is being muted by JFETS when in bridge mode. Getting signal from L channel output at 12K/27K junction.
When scoping output negative terminal I'm getting 36V RMS before clipping
Positive terminal is reading 22V rms.
At this point, I can apply more signal and get 36V on Pos terminal as well, but the negative side is clipping.
With the above 36/22V RMS scenario, I'm reading 58V across NEG and Positive with DVM.
Obviously, far below the specified 800 watts for bridged into 8 ohm load.
Using electric stove hotplates parallel to get a perfect 8 ohms.
Hoping someone can see something obvious here.
I appreciate, and humbly await any response to guide me.
Thanks,
Stan
Okay, I've been lucky with trial, and error troubleshooting, and eventually repairing circuits. Don't want to waste anyone's time here with stuff I should already know. But I just can't figure this one out.
Getting weirdness from bridge mode.
First thing I did was replace the open 27K feedback resistor that had failed open.
In bridge mode, I'm getting a larger signal on negative side (inverted right channel) than I'm getting from the positive side (non-inverted left channel).
Both right, and left channels are putting out the correct wattage in stereo mode.
Bridge switch seems fine. The R channel input is being muted by JFETS when in bridge mode. Getting signal from L channel output at 12K/27K junction.
When scoping output negative terminal I'm getting 36V RMS before clipping
Positive terminal is reading 22V rms.
At this point, I can apply more signal and get 36V on Pos terminal as well, but the negative side is clipping.
With the above 36/22V RMS scenario, I'm reading 58V across NEG and Positive with DVM.
Obviously, far below the specified 800 watts for bridged into 8 ohm load.
Using electric stove hotplates parallel to get a perfect 8 ohms.
Hoping someone can see something obvious here.
I appreciate, and humbly await any response to guide me.
Thanks,
Stan
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