Problem with Deep Blue Delay clone.

[HarryQ]

I recently got a Deep Blue Delay clone.  It was nicely made from a kit, though not by me.  It runs from an external standard 9 volt power supply.  The odd thing is, when you first plug it in to the power supply, and connect it to the guitar and amp, it doesn't work.  It passes signal in the off mode, and the LED lights in the on mode, but there is no effect.  If I unplug the power supply from the box and plug it back in, it works perfectly, and turns on and off with the foot switch fine.  If I unplug it for about 20 seconds, the effect is gone again when I next plug it in, until I unplug the power supply and plug it in again.  Then it works perfectly again.  I'm hoping you kind folks can help me understand what's going on, because this is driving me nuts!  Thanks for any help!

[Ripthorn]

It seems from your description that perhaps the power supply filtering cap might be bad. It might be that it is having trouble either charging up, or it shorts a little bit initially. That is where I would look first.

[HarryQ]

Thanks very much Ripthorn!  I'll check that out.

[antonis]

Brian, your catch should be good only in case of LED powered from different supply..

[duck_arse]

welcome, HarryQ, as antonis might say.

the deep blue delay is PT2399 based, is it not? they are known to lock-up under certain circustances [sic], one being too low a resistance-to-ground on the delay pin (pin 6) at power-on. the other is the grounds problem - some circuits are about that don't connect pin 3 ground and pin 4 ground, upsetting the internals. inspect your board for a link between pins, or just flat out fit one.

[antonis]

welcome, HarryQ, as antonis might say.

My post came AFTER his SECOND post, Stephen... 

[slashandburn]

I second what Duck suggested. I'm no authority on this but what youdescribe sounds a bit like the pt2399 "locking up" which will apparently happen if pins 3 and 4 aren't both grounded.  Seems like an oversight on a few of the pcb kicking about. On the one I found I had to jumper the pins myself.

Jumper pins 3 and 4 and see if it solves it. They should both go to ground anyway so I can't see it doing any harm if its not the issue.

[duck_arse]

welcome, HarryQ, as antonis might say.

My post came AFTER his SECOND post, Stephen... 

the point, antonis, is that a new poster had not been welcomed, by anyone, and he's already at post 2.

[antonis]

welcome, HarryQ, as antonis might say.

My post came AFTER his SECOND post, Stephen... 

the point, antonis, is that a new poster had not been welcomed, by anyone, and he's already at post 2.

I fully empathize with your rightful frustration, Stephen, but I'm not able to establish a formula for posts number/wellcomes received time proportion...

[HarryQ]

Thanks everyone, and I do feel properly welcomed!  I have lots of experience wiring guitars, and I just built a Mod 101 kit amp, but pedal electronics is new to me.  You've given me some great advice, and I'll try not to blow up the pedal.  By the way, it really is a great sounding delay when it's working!

[HarryQ]

Update- I soldered a hard link between pin 3 and 4 of the PT2399, and it worked perfectly!  It now works first time every time!  Thanks very much to everyone who took the time to help a newbie.  You guys are great!

[patrick398]

I fully empathize with your rightful frustration, Stephen, but I'm not able to establish a formula for posts number/wellcomes received time proportion...

Foruhm's Law right? Welcomes received = Posts number divided by Time proportion

[patrick398]

  I'll see myself out.

[duck_arse]

nice one, Harry. if only they was all as easy.

[antonis]

You've given me some great advice..

Not great enough to never mess up with those #@%$ PT2399s, I'm afraid ..