Sparkle boost help

[griffin]

I have build the sparkle boost (thanks Dragonfly). Lay from Veroboard photo bucket, (J201)

I have all the correct values of resistors and caps , but I can't seem to get a reading of 4.5 V from the drain, useing the trim pot it stars at full batt Volts and then drop as I turn it to .1 volts well past 4.5v.

In bypass the effect is just as it should be
but when activated I get nothing.
Please help!

[MartyMart]

Triple  check the wiring/solder bridges - sometimes they are tiny !
in particular around the Jfet sockets.
Also make sure your trimmer isn't bad, I've had three "duff" trimmers lately  !
They can also be VERY sensitive, you may be missing 4.5v by half a millimeter of turn . . .

Marty

[lethargytartare]

...and if you don't have trimpots laying around, just wire in a normal pot -- I found it easier to fiddle with when testing; and then when I got the resistance reading that was right (around 24Kohms), I was actually able to use a smaller trimpot I had laying around.

Good luck!

ltt

[R.G.]

Can you read "What to do when it doesn't work" and give us that info?