I asked Tom McNally if he had any ideas for a new project and he requested a Darling PCB. I thought that was curious, as he can whip them up in a couple hours but I saw where he was coming from. Let's take an easy build and make it *easier*. At the time, I was working on a SE 807/1625 amp and I decided to marry these ideas together. So you can build a 3/4W Darling, or use it to build a 4W trioded 6L6 family amp (ie 6L6, 807, 1625, 6BG6). Obviously you can use other pentodes - like an EL34 - but I'm focusing on the 6L6-types right now. I figure if I tweak one, I tweak them all.
Here's the first run with the Darling build. I used Tom's Darling variant. Obviously, many props to the Darling originator, Bob Danielak. All the voltages tested perfect and I got *exactly* 3/4W.
The Clementine is 3" by 8" and .091" thick with 4oz copper - quite stout. I used the newer Hammond 269EX with 125V primary and my variac set to 120V for power. It is a cute transformer! Output transformers are the Edcor GXSE15-8-5K that I got in a trade from Ed Brown (these are the ones he tested in another thread). I think with the GXSE10-8-5K (the smaller 10W version) that it would be feasible to squeeze this all into the Hammond 6x10x2 chassis, in particular, the 1441-16BK3CWW. If not, the 8x12x2 would be a cinch. Parts to stuff the board minus sockets were $22.
Schematic for a 1626 Darling Build of the Clementine