AION Helios works, but....

[Strat68]

I'm not getting a lot of distortion out of it.  First off, I had to substitute and 741 for the LM308 until I get a 308 in the mail.  Second, the trim pot seems to have no effect.  I did not install Switch 1 (have one or order). 

Is my first problem the 741 instead of the 308? 

The schematic can be found here: http://aionelectronics.com/product/helios-proco-rat-distortion-pcb/

[bluebunny]

Welcome!

So you left out SW1, but did you jumper one of the connections?  Without the switch, none of the clipping diodes are connected to your circuit and it won't distort (much).

[samhay]

As Marc said. But to add, the trimmer is connected to one side of the switch, so it won't do anything at the moment.

[Strat68]

That makes sense.  Thanks everyone.  Now that I look back at the schematic I see what happened.

[samhay]

No problem.

Thanks for linking the schematic, and welcome to the forum.

[Strat68]

Last post on this.  I added a temporary switch until I get the correct size and the pedal is pretty amazing.  Huge gain and a multitude of sounds I've only begun to check out.  I ran it through the distortion channel of my Carvin V3 twin with the Drive (on the amp) set pretty high and it really added some clarity to chords and sounds less "mushy".  Nice feedback as well.

[aion]

Awesome, glad you got it figured out!