[sdiy] asm-1 vco help

[Josh Randall]

I'm having more vco problems.  I have a scope and a multitester. and have
taken some measurment in hopes that somebody will help me.

I put a 5V(from the LFO) triangle on the input of the VCO.  I get a 5V
triangle out of pin 1 of U1 which is what I would have expected.  At the
base of Q1 I get a .1V triangle.  The emitter give a .1V triangle with a
-.5V offset.

The emiter and collector of Q2 has a .1 V triangle wave with a .5V offset.
The base of Q2 is at ground.  I assumed that everything is OK so far
except that turning the 10k trimmer doesn't seem to do anything and I was
expecting it to change the amplitude at the transistors.

The drain(if I got the correct pin) of Q3 is at 15V.  U3 pin 6 is at 15V.

I get a .1 triangle at -.5V offset at 2 of U3.
At 7 of U4 I get a weird rolling hills(or rectified sinewave) with an
amplitude of 25mV.

My guess is that the summer and the exponential converter are working but
that the collector drain oscillator part are not.  The square out signal
is at -7V.

I would apreciate help.  I am almost a total betinner so there is no such
thing as too much handholding.  Let me know if you need more measurments.

Thanks in advance.

sincerly,

Josh Randall