Deep Blue Delay Clone Build

[PRSplayer02]

Hi
I am building a clone of the Deep Blue Delay pedal. I currently have everything set up on a breadboard but when I play my guitar through the circuit there is no delay sound.
The signal is very clean, almost like the effect is bypassed. I have checked everything a couple of times and I cant find the problem.

Any ideas as to what is causing this?

Here is the schematic I am using.
http://revolutiondeux.blogspot.com/2012/01/mad-professor-deep-blue-delay.html

[vigilante397]

Welcome to the forum If you're confident in your layout, post some voltages on the ICs and the 5V regulator. Pictures of the breadboard in question could help in debugging as well.

If everything looks good and you still can't figure out what's wrong, try switching out the PT2399. They can be kind of finnicky, and I've had several builds that gave only clean tone because the PT2399 was fried.

And for your reference, following these steps will help you get help faster: http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

[anotherjim]

PT2399 chip has changed inside - it seems - some won't work unless pins 3 & 4 are connected together.

[PRSplayer02]

Here are the voltages
9vlt battery- 8.91v
Voltage Regulator- pin 1- 4.35v
                           pin 2- 0v
                           pin 3- 5.8v
IC1- pin1- 2.99v
       pin2- 2.88v
       pin3- 2.88v
       pin4- 0v
       pin5- 2.87v
       pin6- 2.87v
       pin7- 2.82v
       pin8- 5.76v
PT2399- pin1- 4.27v
             pin2- 2.13v
             pin3- 0v
             pin4- 1.5v
             pin5- 4.24v
             pin6- 2.13v
             pin7- 0v (after the cap drained)
             pin8- 3.92v
             pin9- 4.01v
             pin10- .72v
             pin11- 2.12v
             pin12- 2.12v
             pin13- 2.11v
             pin14- 2.1v
             pin15- 2.11v
             pin16- 2.11v

[PRSplayer02]

PT2399 chip has changed inside - it seems - some won't work unless pins 3 & 4 are connected together.

I tried this but had no luck, still doesn't work.

[bluebunny]

Something up around your regulator?  Given a 8.91V battery, I would expect most of this to turn up at the regulator.  You didn't sub the 33R (R7) with something much larger?  The power going to the TL072 is similarly short.

[anotherjim]

Something up around your regulator?  Given a 8.91V battery, I would expect most of this to turn up at the regulator.  You didn't sub the 33R (R7) with something much larger?  The power going to the TL072 is similarly short.

++1

[PRSplayer02]

R7 measures 33.1 ohms. Should I try changing this with a 30 ohm for more voltage?

[bluebunny]

R7 measures 33.1 ohms. Should I try changing this with a 30 ohm for more voltage?

Nope.  Somehow you're dropping about 3.1V across that resistor.  Are R20 and R21 really 10K parts?  Together they're a 20K divider with the 33R, so you'd expect most of your nominal 9V at the top of the two 10K.  If they were much smaller parts, then this might explain the 5.8V measurement.

[Renegadrian]

I just got one in front of me, hope those readings help

Here are the voltages
ww - 8.73v

Voltage Regulator
pin I- 8.73v
pin G- 0v
pin O- 5.04v

IC1- pin1-4.33v
      pin2- 4.33v
      pin3- 4.30v
      pin4- 0v
      pin5- 4.30v
      pin6- 4.32v
      pin7- 4.32v
      pin8- 8.73v
PT2399- pin1- 5.04v
            pin2- 2.52v
            pin3- 0v
            pin4- 0v
            pin5- unconnected
            pin6- 0.27v
            pin7- 0.67v
            pin8- 2.52v
            pin9- 2.52v
            pin10- 2.52v
            pin11- 2.52v
            pin12- 2.52v
            pin13- 2.52v
            pin14- 2.52v
            pin15- 2.52v
            pin16- 2.52v

I completely ditched the 33r resistor, it's not so useful, get rid of it and see if the regulator and pin 8 of 072 get the same input voltage. I also cut pin 5 from the chip. 2399 pins 3 and 4 should read both 0v (ground both). pins 8 9 10 have strange voltage readings...

[anotherjim]

PRSplayer... did you measure the battery voltage when it's switched on? It's acting like a bad battery.

[bluebunny]

.

[PRSplayer02]

R20 and R21 both read 10k.  The only substitutions I made where R3 and R18. R3 is 363k where it should be 360k, and R18 is 2.65k where it should be 2.7k

when its on the battery only reads 8.5v

[PRSplayer02]

Re-built the circuit and it's in perfect working order!! Thanks for all of the help!