Sanity check - this is likely to be RF causing trouble, right?

[anotherjim]

You have me puzzled Duck.
Do you mean use that regulator as an AGC control?
I've considered NE570, but it would take me a while to understand how to make it do just what I want -  I can't make head or tail of the application notes!

[snap]

has anyone here tried the TL431 as replacement for the 386 in a this type circuit? only 3 pins!

http://www.diystompboxes.com/smfforum/index.php?topic=101141.0

[duck_arse]

indeed, "tca" was the name I couldn't remember.

http://www.diystompboxes.com/smfforum/index.php?topic=97109.0

is where I got all I know about it. tca is the man.

[anotherjim]

Ok, thanks.
That's a cheap part too - only 20 pennies from my usual source. I will get some next time I order.
Cheers

[duck_arse]

**possibly**, I think, -also- the lm336.

but that's not for quoting.