Try connecting a load across the output to see if that helps the high-side.
Are you using a sinewave or music?
I'm surprised that the external trigger didn't work.
Are you using a sinewave or music?
I'm surprised that the external trigger didn't work.
I can't offer any opinions on the signals without better images.
Have you tried reducing the vertical amplifier settings to give the scope more signal to trigger on?
Have you tried reducing the vertical amplifier settings to give the scope more signal to trigger on?
If you tap on the sencore, does that affect triggering? Mine constantly had problems with bad connections.
If that's loaded with a cap, it's possibly OK but I don't understand why there isn't a break between pulses.
If that's loaded with a cap, it's possibly OK but I don't understand why there isn't a break between pulses.
Yes I deal with bad connections. I need to go into both scopes.
On the signal, It just goes in waves. One pulse will be wide and the next narrow. The driver board must be running correctly because 3 of the amp channels will run clean and good output. It could be the driver chip but I get good drive signals with no outputs in it. So I'm lost at this point. I guess I'll change the driver again. This has really been a teaching moment for me. thank you for all you do.
On the signal, It just goes in waves. One pulse will be wide and the next narrow. The driver board must be running correctly because 3 of the amp channels will run clean and good output. It could be the driver chip but I get good drive signals with no outputs in it. So I'm lost at this point. I guess I'll change the driver again. This has really been a teaching moment for me. thank you for all you do.
Perry, I have a quick question on this amp. I noticed on the channel giving me the problem there's 6VPP on the high side gate with no outputs in it. the other three that are working have 2VPP on the high side gate with no outputs in the amp. I changed the driver chip yet again. Drive signals look good but when I put outputs in all I get is the noise. I think it then knocks out the driver chip. I don't want to try outputs again if it's just going to knock the driver chip out. I have the input to the filter choke lifted. So there's no load on the outputs.
With no outputs in the amp, you won't get high-side drive unless you supply the high-side driver with voltage (generally with a 9v battery). The voltage of the drive will be dependent on the voltage that's supplied.
Final post to this thread. Found the problem with the bad amp channel. Embarrassed to say the problem was as simple as an open resistor. R272A was open. I suspect this caused all the initial destruction. One set of outputs shorted and power supply burned up. Thanks to Perry for all the help. It was a great learning experience.
That appears to have been the resistor that is used to produce the high-side drive for one of the ICs.