Re: ?problem with WH Purple Platypus

Posted by Kalimna on Feb 27, 2018; 3:49pm
URL: http://guitar-fx-layouts.238.s1.nabble.com/problem-with-WH-Purple-Platypus-tp41935p41938.html

Hi Marbles,
I'll get some photo's up tonight along with the voltages, but I think I have the components the correct way around (having followed the schematic and updated layout). However, that assumes I have the correct ECB orientation on the specific transistors I have. I did google the pinouts, but understand these can sometimes differ depending on producer.

The transistor pair currently in the unit are a 2N3904/3906, but I have tried BC550/560, 2N2222/2N2907 and another pair that escapes me right now. All showed similar characteristics. Also a couple of combinations of non-complementary pairs for the hell of it, just to see.

Daft question time - if the transistors are reversed, why would a signal come through at all? Also, do you mean I may have placed the NPN and PNP in their incorrect sockets, or the ECB orientation for each is incorrect.

Many thanks for your help. I *am* slowly learning about the electrickery behind the effects, but it is a long process!

Adam