benjolin troubleshooting

[horrible.heaven]

just finished assembling my benjolin.

is Osc1 supposed to be much higher in frequency (and lower in range) than Osc2? what could be causing this problem? bad cap?

the filter frq and filter res knobs don't seem to work in any coherent way. the filter rungle knob acts almost like a volume knob.

[inlifeindeath]

i'm assuming you etched your own board? honestly, i had some issues with this circuit and it ended up being a tiny cut in a trace. reference the schematic and use a continuity tester to be sure there are no cuts or shorts and check your offboard wiring.

[horrible.heaven]

no, the board's from rob. i'm going to start checking continuity and parts, but i just wanted to see if the sound of the problem signaled any obvious problems.

[rosch]

maybe you confused some resistor value in the oscillator circuit...
both oscillators are about the same and go down well in the sub audio range.
i've had all kinds of minor issues on my self etched boards and after some time spent checking the pcb held against a lamp and comparing with the pcb layout pdf all issues turned out to be caused by several solder bridges i made!
good luck!

[horrible.heaven]

i filed a point back into the tip of my soldering iron and went to work cleaning up the board (there were a couple of solder bridges). oscillator is now working fine. i feel like i should be hearing the effects of the filter a bit differently, but it seems to be working. the PDF of the layout helped a lot. i couldn't read my printed version clearly enough to trace.

[xi-boy]

the layout is fine
i etched my pcb myself and it worked without problems
i love this circuit