Electrovibe LFO circuit voltages

The Gator

Well-known member
So i have built the circuit. Not in a box yet just testing it now. The LFO circuit is not oscillating it seems, as the lamp is just on.
The lamp driver circuit seems ok. The gain and bias make the lamp dimmer or brighter. If I plug in the pedal and use the gain to make the light dim and bright, you can hear the phasing so the signal path seems good.
I am looking for information on what voltage range I should see when measuring at the junction of Q2 emitter, R19 and + side of C14. Basically this is the connection point between the LFO circuit and the lamp driver circuit.
I'm only seeing 6 volts at that junction and nothing seems to change that.
Any thoughts or measurements would be greatly appreciated.
Thank you
Gator
 
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Swapped it out and the lamp started flashing as soon as I powered it up!
I will say, the lamp goes solid "on" at high speed. Perhaps 2k7 on R14 and R15 is too low.
3K3, 4K3, or stock 4K7 is the question now.
After that it will be time to sheield the back of the double pots and put holes in the box. After I box it up I will fine tune it.

Thank you for reminding me to slow down and just look things over thoroughly.

Gator
Any updates? What value did you use for R12?
 
A 5M1 at R12.
Sounds awesome. Super slow is possible when combined with a 2.2 uF at C8.
I think 3k3 or 2k7 could probably be used at r14 and r15 now for the high speed
 
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