This is build number 50, I think and the first time I've heard this problem.
I built the 3 legged dog, in an atempt to "NAIL" a 4049UBE build that
works !!!
It does...... almost, but when "backing off" the gtr vol pot ( which works fine with all other builds )
I get lots of "noise and crackling" going on .. ! ??
Also the 1M gain pot "cuts out" at lower settings and seems "reversed" !
Its connected to pin 6 via lug 2 and pin 7 via lug 3, lug 1 not connected
as per the schemo....
Any assistance would deserve a few beers !!
www.runoffgroove.com --> Three Legged dog project
Thanks,
Marty.
http://runoffgroove.com/3leggeddog.html
the gain pot works like this: the larger the R bewteen pins 6 & 7, the higher the gain. (wiper towards "NC" in the schem =max.);
(I don`t know much about numbering pot-lugs...).
I would insert an Rmin in series with the pot (at least a couple of k`s);
I would also insert an input cap (plus pulldown antipop-R),
coz I don`t trust a FET`s gate...
I like a beer in the later afternoon :)
Thanks Ton :D
Next time you're in London ...... "Beer o'clock" !
Marty.
Are you using a J201? What's your voltage reading on the jfet's drain? You may have to adjust the 8k2 to hit 4.5v (1/2 ps).
Btw, forgot to mention that board and wiring layout are important with this ckt, it can behave quite odd if offboard wiring is too long, or layout isn't right.