I've built Runoffgroove's Modified EA Tremolo (http://runoffgroove.com/eatremolo.html) but I think that the tremolo is a little too deep even when the depth-pot is at minimum so I'd like to mod it a bit. It can be probably be done by changing the values of the resistors connected to the depth-pot (68k and 120k) and the pot itself (250k). What values should I try to make my tremolo less deep?
Just short the two legs of the 68k resistor, so one end of the 250k pot is going to ground. The 68K resistor is acting as a minimum depth limit (and the 120K resistor is acting as a max depth limit). That section of the circuit gives you a 438K (120K + 250K +68K) voltage divider (to divide the LFO voltage from max to zero), that you can only sweep the middle 250K.
I can also recommend running a 0.47uf (470n) cap to ground from the junction of the 120k and 250k pot. That will roll off content above roughly 2.8hz and provide a less obvious pulsation as well as less modulation when you turn the speed up. On mine, I have it as a switchable function. Provides a pleasing variation. Not quite tube-bias tremolo, but moving more in that direction than a stock EA.
Thanks, bypassing the 68k resistor did the trick! Maybe I'll play with the resistor values later (raise the min limit a bit from zero and lower the max limit) but this is good for now. :) And thanks to Mark Hammer for the other tip too, I'll probably try that too.