Tube amp repair

A few years ago I picked up this little gem of an amp at a gun show for a paltry 25 bucks.  Not a bad snag!


It worked great, except the volume knob didn’t seem to do much… it always sounded like it was on full blast.  So, I brought it down to Skullspace to tinker with it.

Aside from the potentiometer not really changing the volume, it was also quite scratchy when changing volumes.  This is usually a sign of a worn-out potentiometer, so I ripped out the old one and temporary wired up a replacement off ebay.

Doing a test run with alligator clips

I carefully tested the amplifier (you really dont want to touch the high-voltage tube supply wires in there when it’s powered…) and it sounded way better than before!  I deemed it a success and installed the new potentiometer, still with test connections:

Dry fit before everything gets soldered

Everything seemed to work alright, so I soldered everything in place:

hand-wired goodness

The only issue I faced was that the old wires did not really wick up the solder so well.  I suspect there are some poor connections because of this, but for now it works… maybe some proper flux paste would work better than rosin-core solder?


Stay tuned for an audio clip!

Gameduino2 test game

Hello internet, I recently received my Gameduino2 via kickstarter and dreamt up a quick demo – tilting the screen moves the ball around (with realistic-ish physics), and keeping it on the “path” longer earns more points:

This demo doesn’t even touch the Gameduino2’s capabilities – just a fun proof of concept.  Maybe someone can build off of it?

Anyways, code is available at, including a pre-compiled .elf file for the arduino Uno.  I am using the Eclipse Arduino plugin from, and have included the project files.  It should still work in the arduino IDE if you remove the eclipse project files – Enjoy!


Don’t try this at home

My little Samsung netbook’s power supply died, so I thought I would see if it was an easy fix. Turns out the components are too tightly packed and coated with silicone adhesive-y stuff to easily find what is broken, but I did manage to shoot a video of a 150VDC capacitor discharge:

And that’s why you shouldn’t tinker with power supplies!