Optimized harmonic tremolo circuit 6G8 fender vibrato

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ELS

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Modified and original.
Was the amp engineer at fender drunk when he designed the original circuit? You can easily delete 4 resistors, 1 capacitor
and 1 triode stage (so no need for that dreaded "only one triode used" socket in these amps). (1 less tube)
Also this would increase gain, you wouldn't need the 2nd stage in the tremolo channel. the way 2 tubes are connected it's a mixer, and has a bit higher gain than using resistors.
And there's like no need for the cathode follower for the tremolo oscillator, I think when the engineer started making the design, it wouldn't oscillate with the .1 caps to ground, so he added the CF, but after reducing the intensity with the 4.7Meg he didn't realize that the CF wasn't needed.
So here's a simpler circuit only needing 2 tubes and does the same thing.

There's more ways to delete parts here but at that point the circuit starts being different, consequently a different sound.
 

ELS

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Maybe this might work, using 4 LDR's, here when one pair of LDR's is illuminated, it filters out the high frequencies to one output tube with the 1nF cap, and the low frequencies of the other tube.
So if you can now just illuminate 2 light sources with opposite phase, it should work.
Someone probably could design a 1 tube harmonic tremolo like this, oscillator, and phase inverter. just that LED's are too low impedance, same with incandescents.
That leaves you with Neon's which are annoying to drive.
And the effect would be twice the oscillator frequency same as in fender's design.
And you could just use 2 LDR's, and have the effect before the phase inverter, still need 2 opposite phase light sources.
 
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