Ok I got 60mv when first connected and this rose upto 200mv, and was still rising, pretty fast.
When I first turned on the amp the waveforms were more pronounced on the emmiter side, then this diminished to this:
There was a lovely peak literally a top half of a waveform, then this quickly dropped to the above
On the base side I got this:
When I first turned on the amp the waveforms were more pronounced on the emmiter side, then this diminished to this:
An externally hosted image should be here but it was not working when we last tested it.
There was a lovely peak literally a top half of a waveform, then this quickly dropped to the above
On the base side I got this:
An externally hosted image should be here but it was not working when we last tested it.
In post #40, only the top was distorted/clipped badly. What have you done to the amp since then?
The waveforms in post #47 are just noise. You'd set the timebase to about 2ms. You'd set the vertical amp to whatever is needed to capture the waveform (approximately the same as you used above). Always post the timebase and vertical amp settings when you post images of the waveforms.
The waveforms in post #47 are just noise. You'd set the timebase to about 2ms. You'd set the vertical amp to whatever is needed to capture the waveform (approximately the same as you used above). Always post the timebase and vertical amp settings when you post images of the waveforms.
Ok, the only thing I have done is bend over Q909 a little so I could reach the legs to pop the probe across. I have changed nothing else.
I don't know if there is a loose connection somewhere on 909?
I tried other timebases and V/div's for testing 909, however I got nothing but a flat line, which didn't change when a tone was played.
I don't know if there is a loose connection somewhere on 909?
I tried other timebases and V/div's for testing 909, however I got nothing but a flat line, which didn't change when a tone was played.
Ok, on the other channel (left side) I get the same deadline, with a little noise.
However I may be having the black probe on the wrong part....
Here's a pic of what i'm doing. The 4 screw heads i'm using as the gnd probe. From the top left I get a waveform on both the bas and emmiter of both left and right channels, however, on the bottom left I get nothing but the noise as descibed above... The bottom left has perfect conductivity with the -ve speaker terminal.
However I may be having the black probe on the wrong part....
Here's a pic of what i'm doing. The 4 screw heads i'm using as the gnd probe. From the top left I get a waveform on both the bas and emmiter of both left and right channels, however, on the bottom left I get nothing but the noise as descibed above... The bottom left has perfect conductivity with the -ve speaker terminal.
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