[Robert Sumption] a.k.a [W9RAS] takes on the daunting challenge of building a WWII spy radio called the Paraset as the topic of this week’s Retrotechtacular. It was originally a tube based CW (Morse code) transmitter/receiver used by the French underground to communicate with the Allies. Many of these radios were dropped behind enemy lines and could run on European AC or 6 V DC with the added advantage of being able to use most anything for an antenna, including fence wire. These small, low power and highly mobile radios tuned in the 3 to 8 MHz range were instrumental in the resistance. But they still make for a really fun scratch-built radio project.

Hobby groups still build this brilliant little radio and use it regularly to make contacts at great distances using the 40 and 80 meter ham bands. This may not be a weekend project for everyone because you need to work with vacuum tubes and build a 400 V power supply to operate this type of radio. Plus, sourcing some of the old components in working order is sometimes near impossible. [Bob] circumvents some of the problems by altering the design to marry up with his surplus supply of radio bits and bobs such as tubes (a.k.a. valves) and FT243 crystals he had on hand. And don’t forget, just as [Bob] says in his 5 part build video seen after the break; “Every day is a Hamfest on eBay”. So getting some of these parts, if not a partial-intact original Pareset radio, is always possible.

If you search on the Internet for “PARASET RADIO” you will find other home-built examples with circuit diagrams and plenty of advice such as found on W7OIL.com and SHAW.ca.

part 1



part 2



part 3



part 4



part 5



Retrotechtacular is a weekly column featuring hacks, technology, and kitsch from ages of yore. Help keep it fresh by sending in your ideas for future installments.