Harmonic Percolator - Q1 hFE?

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Harmonic Percolator - Q1 hFE?

Postby andrewnelles » 15 Feb 2014, 01:02

I'm just about to start work on a Harmonic Percolator clone, and I've got a pair of 2N404A's to work with. One is 105 hFE the other is 160 hFE, which is way higher than what seems to be recommended for this circuit based on digging through some older threads.

I'm working off of this schematic: http://topopiccione.atspace.com/pjimages/HarmonicPercolator.sch.png

If I run with this using the 105 hFE in Q1, will I need to adjust any resistor values to compensate for the higher gain?

Any advice is appreciated, thanks!
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Re: Harmonic Percolator - Q1 hFE?

Postby astrobass » 15 Feb 2014, 03:56

I recall reading in that thread that someone had good results from a Q1 with 180.
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Re: Harmonic Percolator - Q1 hFE?

Postby Alex Frias » 27 Apr 2017, 16:19

Nothing better than your own experience.

Try both and tell us wich one is your preferred!
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