stuck with debug on a Small Clone

[Wounded Paw]

I'm building a Small Clone from the Tonepad layout and cannot get it to work.  The clean signal is passed through fine but no chorus is added to it.  I've checked the IC pin connections over and over and gone over all the traces on pcb for continuity.  I've gone through with an audio probe and found where the problem is but I have no idea what to do now.  On the MN3007 the guitar signal is reaching pin 3 but not pin 1 where it looks like it should be.  After D1 the guitar signal crosses the 33k resistor to reach pin 3 just fine but there is no signal on the other side of the 12k resistor going towards pin 1.  I checked the Q3 transistor voltages and they are C=8.93, B=8.84, E=8.35.  I don't know if this is what they should be or not as I'm not familiar with the ICs the Small Clone uses.  Also by checking pins 2 and 6 of the MN3007 I can hear the pulse coming out of the CD4047.
So what's going on?  Is it possible my MN3007 IC is bad?

Here's where the schematic can be found: http://www.tonepad.com/project.asp?id=8

[Andre]

Preston,

On the MN3007 the guitar signal is reaching pin 3 but not pin 1 where it looks like it should be

It should only reach pin 3. Pin 1 is connected to +9V  via Q3. The 12K resistor is used for setting the bias of the MN3007.

I checked the Q3 transistor voltages and they are C=8.93, B=8.84, E=8.35

These voltages appear to be correct.

Maybe the 4047 doesn't oscillate and the pulses you hear on pins 2 and 6 are from the LFO bleeding through the 4047.

Please check the PCB area around pins 1,2 and 3 of the 4047 for solderbridges.
You could also check D3 and the MN3007 and 4047  for the right orientation and the 150pF cap for right value.

I have built a Tonepad Smallclone myself so If you want I can measure IC voltages for you, but that would have to be tonight since I'm at work right now.

André

[jaytee]

It looks like you have an input at pin 3. Pins 7 and 8 are the output of the MN3007 check there for a signal.

[Wounded Paw]

very strange, I tracked it down to the diodes.  I used diodes from a bag from Mouser clearly marked 1N914 but nothing seemed to be getting past them.  So I used a couple from a very old package marked 914PH that was in the spare parts from my Quad8 mixing console and everything works fine.