Routemaster DIY

Dead simple combined power supply / bus board, suitable for Euro, MOTM, and Dotcom power headers.

Purchasing Options:
Buy for £15 *
Build Document


Routemaster is a simple to build combined power supply and busboard. It can be powered from a 12VAC wallwart, or alternatively a 12VAC centre-tapped transformer.

Options are included for Euro. MOTM, or Dotcom power headers. The supply is adjustable for +/-12V DC or +/-15V DCusing multi-turn trimmers

There is an onboard 5V DCsupply too.

Only available as DIY.

So… what’s it capable of?

LM317 and LM337 are rated at 1.5A each, but to get that much current you’d need a 3Amp AC source, and much bigger heatsinks than those specified! (The bigger the heatsinks, the higher the current that the regulators can operate at). It’s also not great to run the power regulators at or near their maximum rating. I’m recommend assuming that you ask about 500mA of each power rail (+12V 500mA, -12V 500mA) from the supply, assuming a 1A wallwart. The 5V source is rated at 100mA.

Thanks to C.K. for allowing us to share his Routemaster build video:

Product Specifications


249mm x 70mm