Tuesday, 12 April 2016

Quick & dirty DIY Buchla to Euro conversion

These are my quick and dirty DIY notes for a Buchla to Euro power converter.
This blog is my diary for ideas, projects etc that are on going. It helps me to remember details that I usually loose if I don't write down.

This will probably change as I refine the circuit. if you have any suggestions for improvements, please let me know.

Buchla provides -15,+15,+12,+5.
Euro needs +12,-12,+5.
So we need a -12V for Buchla & Euro modules to exist in the same case.
Using a L7912CV voltage regulator.

This was my first attempt using perf board.
In the first attempt, the caps were both 1uF electros

Attempt # 2 ... using a 1uf & 2.2uf cap.

I built this for a friend about a year ago and he reports that it's still happily chugging along.
It might be a good idea to add a heat sink to the regulator. C1 is required for stability. A tantalum is recommended, though in this mock up I used a straight electro.

If electrolytics are used and you are planning to run lots of euro maybe ten times (or more) value capacitors should be selected.???

AND: a high current diode from input to output (1N4001 or similar)
should be introduced to protect the device from momentary input short circuit.

Some new pics care of Cobramatic.
Paul has used tanties and he reports no problems.
This board doesn't use a heatsink -- will see how this goes over time.

The Buchla (BEMI) power board is on the top.

I take no responsibility if this damages any Euro or Buchla modules or starts a fire. 
Modular gear requires care and more that a casual understanding of electronics.
Don't build this if you are not totally confident with your soldering skills.
These are just working ideas that will be refined over the coming years.


  1. This is a great idea. Look forward to seeing where it goes..

  2. Many electronic products are directly marketed by the manufacturing companies. Many wholesalers also offer attractive gifts on bulk buying of the electronic items. transistor