pushme pullyou gain pot is not functioning

[gtfitzie]

Built a pushme pullyou from original schematic and the gain pot is not functioning.

Here's is Voltage of the transistors

2N3904 Q2    2N3906 Q3  2N3904 Q1
E - 3.88           E - 3.88     C - 4.61
B - 4.45           B - 4.31     B - 2.70
C - 4.96           C -4.96      E - 2.13

Help would be appreciated, it's my first try

gtfitzie

[PRR]

> pushme pullyou from original schematic

Give link! Not everybdy has everything memorized.

This?? http://iopscience.iop.org/1367-2630/7/1/234/fulltext

Or this?? http://folkurban.com/Site/PushmePullyou-716.html

It appears your gain pot is much larger than 1K; however if the cap at the wiper is connected correctly, it should vary gain.

[gtfitzie]

The schematic i used is from www.folkurban.com

The gain pot is a 5k

[petemoore]

  Q1 has the gain pot wafter value which sets bias.
 1k emitter / 10k collector resistor sets this up as a booster.
 With 5k emitter resistor the voltage of emitter will tend to be high as shown in the voltages taken, reducing operational swing voltage.
 Try a 1k5 or 2k2 across the 5kpots outside lugs to build a reduced value fixed E resistor to about 1k [measure what you end up with or visit resistor calculator or calculate it].