"Little Angel" - Super Simple PT2399 Mini Chorus

[bluesman1218]

hello, how I can do to increase the volume of the signal delay? o maybe add a mix control.

Check Post #562 on this page. I'm thinking of using this version for my next build of this pedal.

[ppaappoo]

hello, how I can do to increase the volume of the signal delay? o maybe add a mix control.

Check Post #562 on this page. I'm thinking of using this version for my next build of this pedal.

OK, thanks. I'm working in this chorus http://www.diystompboxes.com/smfforum/index.php?topic=90835.0

[frequencycentral]

hello, how I can do to increase the volume of the signal delay? o maybe add a mix control.

Little mod for anyone who's interested try changing the resistor connected to pin 15 to 22k, that makes the wet side a bit louder and sounds more chorusy to me. It might mess with to overall level though.

[GodSaveMetal]

I had a similar problem with my last build. Here's what it boiled down to for me -
1. make sure the 100R is 1k - it has to do with the PT2399 locking up
2. check the 330K behind the voltage regulator - mine drifted in value
3. check the 1meg from pin 7 on the opamp

In bypass. everything was fine, but no signal at all with the effect on. I found that when I touched the back of the PCB in the output path, I got hum .
I also a - touched up my solder connections
        b - checked every solder joint and trace for continuity and solder bridges
The end result was #3 above
#2 above took care of my voltage readings

Hope this helps. I was very pleased with the build once it was working.

Hi thanks for your input
Can you clarify what you mean by checking the 1M and the 330K? Do you simply mean checking their resistance is accurate?
I did indeed use a 1k rather than the 100R resistor mentioned.
[/quote]

Yes, that's what I meant.
[/quote]

You tried to change the PT2399?? I change it with the original values and work fine with the new IC!!!!! some PT2399 can be failure!!!!!!!!!!!!!

[ppaappoo]

hello, how I can do to increase the volume of the signal delay? o maybe add a mix control.

Little mod for anyone who's interested try changing the resistor connected to pin 15 to 22k, that makes the wet side a bit louder and sounds more chorusy to me. It might mess with to overall level though.

[Earthscum]

If you swap the positions of the caps into the resistors' spots at the mixing section, and just put a 20k pot in where the caps were, outer to each cap, and wiper to where the caps used to tie together in the board, you have an adjustable mix. I would probably 'fly' in 4.7k's from either leg and use a 10k, though to limit the amount on either side. Or breadboard and find that sweet mix... 3.3k from the dry side and 5.6k from the wet into a 10k? Just ideas for ya.

on a side note, I keep ignoring this thread when it comes up because it makes me want to build an 'Uber-Angel', a bit of tweak-ability on everything. I already have two extra knobs on my angel, don't need more... but I got etch-happy and have a spare couple boards I really want to use, and maybe together... parallel, in the same box. It would be easy to do using what I described above to mix, then just a buffer and a mix to get them back to a single signal, a level pot, adjustable delays on both... ugh. Rick, I think an Angel might get a Rack... and I still want to make another Toe Jam, gotta finish my friend's Rat, rework a couple distortion designs... my girlfriend doesn't think I love her as much as the circuits. 

[Earthscum]

Oh yeah, Rick, I forgot to mention that I've been having no problems firing up ANY PT with 820R so far. 680R was kind of a crap shoot... out of the batches of newer ones, I wouldn't trust one that worked to keep it up forever. My first PT's still fire up fine with the 100R, as I'm sure all yours do too.

[bluesman1218]

You tried to change the PT2399?? I change it with the original values and work fine with the new IC!!!!! some PT2399 can be failure!!!!!!!!!!!!!

Before building, I ordered 3 PT2399s after reading the thread. Everything works fine once I fixed these problems.

[GodSaveMetal]

You tried to change the PT2399?? I change it with the original values and work fine with the new IC!!!!! some PT2399 can be failure!!!!!!!!!!!!!

Before building, I ordered 3 PT2399s after reading the thread. Everything works fine once I fixed these problems.

I have a problem with one of my PT2399 how to fix em`??? yeah the other sound normal with no changes??? my PT2399 is wrong??? there is no effect with it the sound pass normal!!!!

[frequencycentral]

mictester over at the other place has developed a little sub-circuit to prevent the PT2399 from locking up:

 "The PT2399 datasheet warns about having a low value resistor from pin 6 to ground during the power-on reset that the IC does automatically. The reset lasts 400 ms. I keep pin 6 with a higher value resistor for longer than the reset period. I tried it, and the three ICs I tried it with did not lock up. With the 2N3904 I used, the delay was pretty much identical to that from a 100R resistor. "

It would appear to be verfied twice. Should solve people's problems with some PT2399 not liking this circuit.

[ppaappoo]

You tried to change the PT2399?? I change it with the original values and work fine with the new IC!!!!! some PT2399 can be failure!!!!!!!!!!!!!

Before building, I ordered 3 PT2399s after reading the thread. Everything works fine once I fixed these problems.

I have a problem with one of my PT2399 how to fix em`??? yeah the other sound normal with no changes??? my PT2399 is wrong??? there is no effect with it the sound pass normal!!!!

some PT2399 don't work with the 100R resistor to ground in the pin 6, try with 560R.

[Govmnt_Lacky]

Modest request 

Could someone post a link to a good, recent demo for this pedal WITHOUT ANY OTHER EFFECTS IN THE CHAIN?

I still feel that my build sounds VERY, VERY Subtle compared to some of the demos I have heard however, most of those were used with delays, reverbs, etc.

I used 100K for both pots but others have done the same and their demos sound FAR better than my Angel.

[ralley]

Modest request 

Could someone post a link to a good, recent demo for this pedal WITHOUT ANY OTHER EFFECTS IN THE CHAIN?

This one (not my demo) seems to be Little Angel only: http://www.youtube.com/watch?v=tsbcD4txfZg&feature=related

Rob.

[cgibsong002]

I searched through the last 10 pages but didn't see anything... is there a vero layout for this?

[ppaappoo]

I searched through the last 10 pages but didn't see anything... is there a vero layout for this?

page 4! 

[cgibsong002]

I searched through the last 10 pages but didn't see anything... is there a vero layout for this?

page 4! 

there was a pcb layout there but not a vero.

[frequencycentral]

I searched through the last 10 pages but didn't see anything... is there a vero layout for this?

http://www.sabrodesign.com/wp-content/uploads/2010/10/Little-Angel.gif

[cgibsong002]

I searched through the last 10 pages but didn't see anything... is there a vero layout for this?

http://www.sabrodesign.com/wp-content/uploads/2010/10/Little-Angel.gif

awesome thank you so much. is this the modified 'fixed' version?

[hab]

Here's the version with mictester's "lock-up" fix (yet to be verified): http://www.sabrodesign.com/wp-content/uploads/2011/04/LittleAngelRev1.gif

[robmdall]

What is the group choice schematic to follow? Ricks original (version 2) or Earthscum's (post 141) ?

Bob