Sample Rate Reducer

[dustfilledhobo]

Today I attempted to build a Sample Rate Reducer guitar pedal, but something is wrong.  When I turn on the pedal the LED flashed, but almost instantly turns off.  I am using a design that I found here:  Schematic

I used j201 for Q1 as suggested, perfboard and point-to-point soldering, I wasn't sure which op amps to use, so I used two LM358's, and I used the suggested 1n914 diodes.

Here are some voltages that I measured with a 9.23 V battery connected and the effect on:

X1 and X2: LM 358 (datasheet)
1:  7.66 V
2:  7.66 V
3:  3.84 V
4:  0.00 V
5:  7.02 V
6:  7.04 V
7:  7.04 V
8:  9.23 V

X3 and X4: LM 358 (datasheet)
1:  0.15 V
2:  7.64 V
3:  4.19 V
4:  0.00 V
5:  7.65 V
6:  0.05 V
7:  7.91 V
8:  9.23 V

Q1: j201 (datasheet)
(I don't know much about jfet transistors, so this one I will use left center and right, where I'm assuming the flat side is away from me)
L:  7.67 V
C:  7.02 V
R:  7.03 V

D2: 1n914
A:  0.04 V
K:  0.14 V

D1:1n914
A:  0.14 V
K:  .04 V

RED LED (I added this in series with 1k between the battery and Vb)
A:  9.16 V
K: 7.65 V

Thanks again for the help everyone always gives me.

Dusty

[oldrocker]

Since the LED is the bypass try going straight in and out first.  As for the LM358 I'm not sure what effect that will have.  I used TL082's.  When you get it working these are some component swaps I did which IMHO improved it.
I used 1n34a GE's in place of the 1n914's.  I replaced C4 from a .0033uf to a .1uf cap.  I switched R7 from a 100k to a 47k.  The last two changes were to stop uncontrolled sqeal and oscillation.

[TELEFUNKON]

here is the original project: http://www.diystompboxes.com/smfforum/index.php?topic=48809.0

[dustfilledhobo]

Thanks for the replies.  I'll definitely try your mods once I get this figured out, and I'll check out the original project when I have a chance.  Thanks again.

Dusty