debugging booster 2.5

[ward]

Hi there,

I'm debugging a Aron Nelson Booster 2.5.
First I breadboarded it, and liked it so I made it on perfboard now.


But ... No sound at all.

I subbed some components, fets are BF245a, capacitor at the tonepot is different.
But it worked on the breadboad so that should not be the problem

So what I have checked from my little experience ...
In bypass I have sound
The inputsignal, outputsignal, V+ and V- all make it to the board.
Supplyvoltage is 8.07V after the protection diode.

Now what ...

I went looking over here and found the "debugging the sparkle boost" thread.

For an N-channel JFET to be working as a linear amplifier, there's a different set of data than for a bipolar. The source must be more positive than the gate, and the amount of that more positive has to be less than Vgsoff. The drain of the JFET has to be lower than the power supply and have some voltage between it and the source to wiggle around. If it's at the source voltage, the JFET is saturated, and not much if any signal gets through.

Q1: g=7
      s=6.15
      d=5.77
Q2: g=8
      s=7.05
      d=7
Q3: g=6.9
      s=6.03
      d=6
Q4: g=7.9
      s=7
      d=6.94
None off my voltages are ok ... 

[ward]

This is the schem I followed, I added Q1,2,3 and 4 markings

[ward]

Hmm, I have this feeling I put all the JFets in wrong.

 



If I followed this without thinking than logically all my gates and sources are reversed.
Hope I can get them out without destroying them.

Sorry for the rambling and thanks for reading.