First Build Proco Rat "La Rata" from Tonepad - very little output volume

[DarntheRat]

Hello,

My effect appears to work only the output volume is extremely low.  I have used an audio probe to go through the circuit and it distorts etc but doesn't not seem to get reamplified.  If I add gain on my amp I can hear the effect. 

http://www.aronnelson.com/gallery/main.php/v/the+rat/

Voltages on chip

7.9          4.34
4.31        8.56
2.08        4.29
0            4.29

on J-Fet

8.59
1.34
0

Thanks for any advice//

[sasuke_kun12]

have you made any part substitutions?

[DarntheRat]

Hi,

thanks for the reply...I have a couple of large voltage pF caps...the 30pF cap above the chip and the 100pF cap beside it are both rated to 500V. 

[Mark Hammer]

Those will not make any difference.

Other than solder bridges, bad pots, fractured wires or pins bent under the IC when inserting into a socket, the most typical culprit is going to be your JFET pins.  Only 3 pins, but so many possibilities!  And if my experience is any indication, the "correct" pinout will be the 4th or 5th you try.

[DarntheRat]

Can you clarify that a little.  I'm using the 2N5458 from the specs...should I be trying a different J-FET or are you suggesting the ones of got don't work.  I've bought another 2 to try because I though I may have overheated the first one when soldering.  Neither make a difference.

Cheers

[Mark Hammer]

Nothing quite that complicated.  I'm just suggesting that in the process of mentally rotating poorly drawn pinout diagrams, manufacturer to manufacturer differences, and JFET to JFET differences, you may just have one or more pins of the 2N5484 going to the wrong pad.  It happens.....a lot.