madbeanpedals::forum

I unfortunately missed out on the dirtbaby's short stock and I went ahead and tried the LED limiting mod on my deep blue delay... unfortunately I think its killing my pt2399's.

i am definitely going from pin 7 to pin4.

will this mod work on a deep blue clone?  or do i need to do something else to the circuit?

Connect it to pin 3. Pin 4 is not ground on the deep blue

Quote from: Matt on December 15, 2014, 12:07:26 PM
Pin 4 is not ground on the deep blue

Whilst that is strictly true for the original, a lot of people connect 3&4 to GND as this fixes an issue with certain PT2399 chips.

Make sure you have the anode on pin 7, and make sure that your pin4 is actually connected to analog ground.

*Checks upon Dirtbaby pdf*

*realizes what he has missed*

well i just quadrupled checked everything- got a new LED confirmed positive and negative legs.  confirmed pin 4 goes to ground.  put positive of the LED to pin 7 and negative to pin 4.  (both pin 3 and 4 connected to each other) 

and i fried another pt2399... that's 4 good pt2399's gone :(

Quote from: claytushaywood on December 16, 2014, 03:46:37 AM
well i just quadrupled checked everything- got a new LED confirmed positive and negative legs.  confirmed pin 4 goes to ground.  put positive of the LED to pin 7 and negative to pin 4.  (both pin 3 and 4 connected to each other) 

and i fried another pt2399... that's 4 good pt2399's gone :(

Chin up man, I get more than that bad in one tayda order :]

Cody

Quote from: claytushaywood on December 16, 2014, 03:46:37 AM
well i just quadrupled checked everything- got a new LED confirmed positive and negative legs.  confirmed pin 4 goes to ground.  put positive of the LED to pin 7 and negative to pin 4.  (both pin 3 and 4 connected to each other) 

and i fried another pt2399... that's 4 good pt2399's gone :(

I don't understand how this is possible. I don't doubt it, but are you sure they are fried and not temporarily locked up somehow? Have you tried grounding all the pins and re-checking it? What are the exact voltage measurements you get on pins 7, 3 and 4?

I have no idea about locking up pt2399s!  How exactly would I go about grounding each pin? Just individually connect.each pin to ground while powered on?

Quote from: sturgeo on December 15, 2014, 12:42:00 PM

Quote from: Matt on December 15, 2014, 12:07:26 PM
Pin 4 is not ground on the deep blue

Whilst that is strictly true for the original, a lot of people connect 3&4 to GND as this fixes an issue with certain PT2399 chips.

I wasn't aware of this, thanks.

Quote from: madbean on December 16, 2014, 09:37:03 AM

Quote from: claytushaywood on December 16, 2014, 03:46:37 AM
well i just quadrupled checked everything- got a new LED confirmed positive and negative legs.  confirmed pin 4 goes to ground.  put positive of the LED to pin 7 and negative to pin 4.  (both pin 3 and 4 connected to each other) 

and i fried another pt2399... that's 4 good pt2399's gone :(

I don't understand how this is possible. I don't doubt it, but are you sure they are fried and not temporarily locked up somehow? Have you tried grounding all the pins and re-checking it? What are the exact voltage measurements you get on pins 7, 3 and 4?

sorry I forgot to quote you on my last post-

how do i unlock the pt2399?  Do I just hook up the deep blue to my breadboard and power it then use a jumper cable to go to ground on the pins individually?

Quote from: claytushaywood on December 16, 2014, 09:06:40 PM

Quote from: madbean on December 16, 2014, 09:37:03 AM

Quote from: claytushaywood on December 16, 2014, 03:46:37 AM
well i just quadrupled checked everything- got a new LED confirmed positive and negative legs.  confirmed pin 4 goes to ground.  put positive of the LED to pin 7 and negative to pin 4.  (both pin 3 and 4 connected to each other) 

and i fried another pt2399... that's 4 good pt2399's gone :(

I don't understand how this is possible. I don't doubt it, but are you sure they are fried and not temporarily locked up somehow? Have you tried grounding all the pins and re-checking it? What are the exact voltage measurements you get on pins 7, 3 and 4?

sorry I forgot to quote you on my last post-

how do i unlock the pt2399?  Do I just hook up the deep blue to my breadboard and power it then use a jumper cable to go to ground on the pins individually?

Often the chips will unlock after a day or two on their own. Your breadboard idea would be fine. I don't think you necessarily have to ground all the pins simultaneously, it's just to remove any stored capacitance. (Which drains over time, hence why I said that they usually unlock on their own after a day or two.)

I can't think of anything about the LED mod that would do what you've described. It simply conducts when the voltage on pin 7 rises to ~1.8V or higher, and it's been done in about 5 different designs now.

Quote from: midwayfair on December 16, 2014, 09:27:06 PM
Often the chips will unlock after a day or two on their own.

Interesting.

Whenever I've had a PT lock up, I kill power to the whole circuit, wait 10-15 seconds, and power back up. Seems to solve the issue.

Quote from: Muadzin on December 15, 2014, 02:24:29 PM
*Checks upon Dirtbaby pdf*

*realizes what he has missed*

me toooooooo!

Quote from: culturejam on December 17, 2014, 02:21:49 AM

Quote from: midwayfair on December 16, 2014, 09:27:06 PM
Often the chips will unlock after a day or two on their own.

Interesting.

Whenever I've had a PT lock up, I kill power to the whole circuit, wait 10-15 seconds, and power back up. Seems to solve the issue.

thanks.  i promise you i am doing everything correctly.  i've tried it 4 times over about 3 days checking connections, checking LED's, having working pt2399's to begin with, checking voltages, everything.  its not exactly a difficult thing to do.

and now my pt2399s dont work.  ill check em tomorrow to see if theyve unlocked or if theyre donezo. 

I believe I'm using those terribly dim LED's that tayda used to carry (maybe still does) and I used a 3mm diffused green LED.

For unlocking I always found just grounding each pin on my testing rig seemed to do the trick. You probably don't even need to do that---just pins 1 - 8.

Quote from: atreidesheir on December 17, 2014, 02:25:07 AM

Quote from: Muadzin on December 15, 2014, 02:24:29 PM
*Checks upon Dirtbaby pdf*

*realizes what he has missed*

me toooooooo!

Somebody made a vero layout here:

http://guitar-fx-layouts.42897.x6.nabble.com/Madbean-Dirtbaby-tp15783.html

It boggles the mind why something as awesome as this was just a temporary project.

I believe he is planning on making it a regular project or at least doing a larger limited release at some point.
Also, I saw the vero... I enjoy vero but this is one of those cases I would opt for a pcb. Gotta hand it to the people building crazy large veros though.

Quote from: Luke51411 on December 17, 2014, 02:15:23 PM
I believe he is planning on making it a regular project or at least doing a larger limited release at some point.
Also, I saw the vero... I enjoy vero but this is one of those cases I would opt for a pcb. Gotta hand it to the people building crazy large veros though.

It's been moved from short runs to the delay section on the projects page, with a release date of jan 2. Happy days!

this project is just prone to locking up my pt2399's- ive never had this problem before but I guess its common.  I changed the opamp and it locked up a chip.  I did unlock one, but then I went and changed the opamp- power disconnected and everything and locked it up again but now I cant get it unlocked.  i've got a few that I cant unlock actually... I've been putting the pcb on my bread board and using an alligator jumper to connect pins to ground.  Can I unlock them without power?

maybe the project I'm using is the culprit?  I'm using rullwowr's deep blue delay board... it looked like a straight deep blue delay copy- but ive historically had all sorts of troubles with the deep blue delay... i mean all sorts.

i do have a sparklehorn has anyone tried the LED trick on that project?

Have you connected pins 3 & 4 together permanently?? I've checked the Rullywow build doc and the schematic hasn't got them connected?


Edit: I'd leave the LED out for now, try to get the circuit working reliably as it should first.

No, I havent connected pins 3 and 4 permanently... should i do that?

I do have the circuit working, itd be reliable as long as I dont mess with it, but like I said, changing the opamp has caused the pt2399's to lock up on several occassions.

Yup, i do on all of mine.
It seems some PT2399s lock up randomly, mostly those sourced form tayda...

It doesn't appear to have any adverse affects, the first dbd i built on vero had the link: http://tagboardeffects.blogspot.co.uk/2012/02/mad-professor-deep-blue-delay.html (http://tagboardeffects.blogspot.co.uk/2012/02/mad-professor-deep-blue-delay.html)

Quote from: claytushaywood on December 21, 2014, 07:49:01 PM
No, I havent connected pins 3 and 4 permanently... should i do that?

I do have the circuit working, itd be reliable as long as I dont mess with it, but like I said, changing the opamp has caused the pt2399's to lock up on several occassions.

Yes, connect them.

connecting pins 3 and 4 together fixed all my problems!  they both showed continuity to ground but since ive hard wired them together i havent had a pt2399 lock up yet and i was able to use the LED limiting.  Now i've got a deep blue delay running at 18v with a charge pump.  killer