The triangle out is working, but square out is not. There isn't much
to what converts the triangle to square, so I thought I could figure
it out. While looking around for bad solders or anything else I had
my headphones plugged into the square out. I started to get a tone..
definitely a square wave. I figured out that if my thumb was touching
pin 8 on the tl072 and the area around sync in or the 100p cap, I
would get square wave. From there I figured out that if I touch pin 3
of the lm311(sync in) and +v the square wave works, however it
distorts the saw out.
I accidentally discovered that if I short the 100k resistor just right
of the 311 it produces a tone out of the sq. out(though it sounds
different). Its connected to a bunch of stuff on the pcb, including
the output of the ca3140.
Ive checked the components all around those portions of the circuit.
I dont understand why messing w/the sync would make the output from
the square work. Should I be looking around the tl072, or the lm311?
Any clues what the cause might be?
thanks
to what converts the triangle to square, so I thought I could figure
it out. While looking around for bad solders or anything else I had
my headphones plugged into the square out. I started to get a tone..
definitely a square wave. I figured out that if my thumb was touching
pin 8 on the tl072 and the area around sync in or the 100p cap, I
would get square wave. From there I figured out that if I touch pin 3
of the lm311(sync in) and +v the square wave works, however it
distorts the saw out.
I accidentally discovered that if I short the 100k resistor just right
of the 311 it produces a tone out of the sq. out(though it sounds
different). Its connected to a bunch of stuff on the pcb, including
the output of the ca3140.
Ive checked the components all around those portions of the circuit.
I dont understand why messing w/the sync would make the output from
the square work. Should I be looking around the tl072, or the lm311?
Any clues what the cause might be?
thanks