Hi all,
I'm helping a friend fix up a non-functional tremolo on a 60's BF Twin Reverb (AB763) and I'm trying to narrow down the likely problem areas.
The oscillator circuit and lamp work fine, but max-ing out the intensity only gives a faint motor-boating effect. I suspected the photocell and removed it from the circuit to test it. At normal room illumination it shows about 60ohms and shining an LED directly on it gives a decrease to about 30ohms so it does function as expected, but I'm not sure if these resistance values are normal spec.
Can anyone shine any light on whether the photocell needs replacement (and if so, where to get one from) or if there is something else I need to look at in the circuit? Your assistance is much appreciated.
I'm helping a friend fix up a non-functional tremolo on a 60's BF Twin Reverb (AB763) and I'm trying to narrow down the likely problem areas.
The oscillator circuit and lamp work fine, but max-ing out the intensity only gives a faint motor-boating effect. I suspected the photocell and removed it from the circuit to test it. At normal room illumination it shows about 60ohms and shining an LED directly on it gives a decrease to about 30ohms so it does function as expected, but I'm not sure if these resistance values are normal spec.
Can anyone shine any light on whether the photocell needs replacement (and if so, where to get one from) or if there is something else I need to look at in the circuit? Your assistance is much appreciated.
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