Routemaster DIY

  • 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 or +/-15V using multi-turn trimmers
  • There is an onboard 5V supply too.
  • Dimensions: 249mm x 70mm


So…what’s it capable of?

LM317 and LM337 are rated at 1.5A each. However, to get this much juice you’d of course need a 3A AC source. As well 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.


Route case

Routemaster PCB: £15 GBP

Build documentation: Routemaster Build Document

For orders and queries please contact me at:

[email protected]