Been using a self built, Heathkit audio preamp for many years. Never had reason to try the moving coil amplifier until recently; then found that the right channel is not functioning.
I've been experimenting with hobbyist level electronics repair, with some success and failure. Going to try to fix this myself. I have, and am ok with a digital multimeter. Someone gave me a function generator and oscilloscope which I've yet to use.
I have the original Heathkit schematics. The m/c amplifier board is easily accessible and removable from the pre-amp. The pcb is fairly simply by today's standards. My questions refer to test equipment capabilities and methods.
It would seem to make sense, with the preamp power on and the m/c board in place, to attach the function generator to the m/c imput jacks of the preamp (I already checked for continuity on both channels from the jacks to the selector switch board; no problems.) Assuming that the function generator would send a signal through the m/c amplifier and I could check voltage at each point through the two circuits, comparing right channel to left channel. When I find a difference between the two channels, I could pull the component and check it. I think that that assumes that the function generator will send a signal though the board without any additional current or signal; and I do not need to connect to a load, like a speaker, or headphone output?
Is my thinking correct; what am I missing?
Thanks for the help.
I've been experimenting with hobbyist level electronics repair, with some success and failure. Going to try to fix this myself. I have, and am ok with a digital multimeter. Someone gave me a function generator and oscilloscope which I've yet to use.
I have the original Heathkit schematics. The m/c amplifier board is easily accessible and removable from the pre-amp. The pcb is fairly simply by today's standards. My questions refer to test equipment capabilities and methods.
It would seem to make sense, with the preamp power on and the m/c board in place, to attach the function generator to the m/c imput jacks of the preamp (I already checked for continuity on both channels from the jacks to the selector switch board; no problems.) Assuming that the function generator would send a signal through the m/c amplifier and I could check voltage at each point through the two circuits, comparing right channel to left channel. When I find a difference between the two channels, I could pull the component and check it. I think that that assumes that the function generator will send a signal though the board without any additional current or signal; and I do not need to connect to a load, like a speaker, or headphone output?
Is my thinking correct; what am I missing?
Thanks for the help.