GGG EA tremolo correction & debug question

[dubs]

Correction: wire from middle lug of speed pot should be connected to ground (the right lug). Wiring the other way as on layout makes got turn in reverse.

Question: What is additional transistor for in the new layout to the older layout?

Debug: Made the GGG layout, wired it for led pulsing which works o.k. I get signal coming thru loud and clear when effect is on but no tremolo effect (but can hear faintly in the backgorund). I perhaps question the wiring layout of the depth pot on the new layout as it seems different  to the old geofex layout.

[aaronkessman]

i built the old version from GGG. have not tried making the pulse LED function, but i plan to.

that first transistor is a buffer stage. the version on runoffgroove.com cindenses that circuit back down to 3 transistors by (somehow) using that first transistor for a buffer too.

hope this helps somwhat ;-)

aaron

[dubs]

Thanks, got it working o.k. Found using Mpf102 transistors in Q2 and Q4 had little tremolo effect , then replaced with 2n5457 in Q2 and it worked o.k. Strange as I built geofex 3 transisotr layout and MPf102 worked o.k.

I did the pulsing led by soldering a led & 10k resistor on r8 (15K) and changing R7 to 390k resistor.