Shared Projects by AudioGeek

Hole and Pad Size Reference.

Don’t find out the hard way that your 1N4007 rectifier diode leads won’t fit in a 0.9mm hole! :)

Plug a dual-triode vacuum tube (12A*7) into a breadboard. Or do it dead bug style with the screw terminals. Yay.

Add 0.5" hex standoffs to rear holes to support tube/board weight when plugged into breadboard.

I have used this board a bunch on a recent project, and it really beats soldering a bunch of wires to the pins of a plain tube socket!

LM386N-3 chip audio amplifier PCB. I power this with 12V DC (Add a 100µF electrolytic filter/smoothing cap across the DC power input if using a wall wart). The other values are:

R1 10 Ω ½W metal film resistor
C1 0.1 µF 50V electrolytic capacitor (or a ceramic or film cap)
C2 0.047 µF 100V box film capacitor
C3 330 µF 16V electrolytic capacitor

I have used this PCB in a couple of projects and it works well. Low noise and very compact. It operates in 20x mode (You can always bodge on a 10µF electrolytic between pins 1 and 8 if you want noisy 200x mode).