SOLVED Parenthesis mini

[chongmagic]

I built a Parenthesis mini, and I get nothing but a clean signal even with the distortion pot all the way up. Filter and amplitute seem to change and the octave and boost work but no distortion what so ever. I used a LM308 and the voltages at the pins seem ok. I am guessing it could be the IC is bad. I don't think any tranny's directly effect the input to the chip, but does anyone have the voltages so I can compare?

 

[Nostradoomus]

I think I had that same problem and it turned out to be the JFET in the rat circuit. I’ll get some voltages for you though, give me a bit.

 

[chongmagic]

I think I had that same problem and it turned out to be the JFET in the rat circuit. I’ll get some voltages for you though, give me a bit.

Awesome thank you!

 

[Nostradoomus]

I used 2n5458 in place of the 5102s.

Supply voltage : 9.08

From left to right on the board top down.

2n5458 #1
8.85
1.91
0.0

2n5458 #2
8.85
2.71
0

I can do the other transistors too if your voltages for the JFETs are good, but they are mostly parts for the octave and clean circuit so I don’t think they are the issue.

 

[Nostradoomus]

Sorry and the IC (dist at max), used a metal can UA308 for fun

1- 8.85
2-4.44
3- 3.8
4- 0
5- 0
6-4.44
7- 8.9
8- 4.1

 

[Bobbyd67]

Have you got a lm741 to test ? Had troubles with my build... Turn out I bought some fakes on eBay... What a surprise xD. With the new ic everything works like a charm

 

[chongmagic]

Sorry and the IC (dist at max), used a metal can UA308 for fun

1- 8.85
2-4.44
3- 3.8
4- 0
5- 0
6-4.44
7- 8.9
8- 4.1

Thank you so much, I will take a look at Q5, and see if my voltages match yours. From memory I believe my IC voltages where around the same as yours. I don't have another on hand to compare with, people keep wanting to buy the ones I build. So I planned on keeping this one myself, and of course I have an issue with it. LOL.

 

[chongmagic]

It was the chip that was bad. I got it from JAMECO too.

 

[K Pedals]

It was the chip that was bad. I got it from JAMECO too.

I just bought 100 2N5457s from them and like 61 of the 100 were bad...

 

[chongmagic]

I just bought 100 2N5457s from them and like 61 of the 100 were bad...

I just bought a bunch of 2n5457s from Mouser, I hope it won't be the same case.

 

[K Pedals]

I just bought a bunch of 2n5457s from Mouser, I hope it won't be the same case.

I’ve never had a problem with mouser
I order a lot of stuff from them...
For some reason I thought they didn’t have any 5457s... I should have just bought them from mouser...

 

[Nostradoomus]

I don’t trust any through hole j201 or 2n5457 any more. I’ve found some good 2n5458 though.

 

[K Pedals]

I don’t trust any through hole j201 or 2n5457 any more. I’ve found some good 2n5458 though.

Yeah they seem to be few and far between now a days...

 

[Nostradoomus]

That and the legit ones are so outrageously priced. I can get 10 mmbf5457 and 10 adapter boards for the same price as one haha

 

[chongmagic]

Not cheap, but I got a few to have on hand, I am not sure how much longer they will be around.

I have used some J201s from Pedal Hacker and they have been fine thus far, and got some from GuitarPCB and they were fine as well.

 

[K Pedals]

Not cheap, but I got a few to have on hand, I am not sure how much longer they will be around.

I have used some J201s from Pedal Hacker and they have been fine thus far, and got some from GuitarPCB and they were fine as well.
View attachment 2921

You mean those mpf102’s from pedal hacker??
I got some of those too....

 

[chongmagic]

You mean those mpf102’s from pedal hacker??
I got some of those too....

Back almost a year ago they had some J201s in 10 packs and I bought like 4 packs.