Even in the strange and eccentric world of the ham radio operator, Fred Judd G2BCX (1914–1992) was something of an outlier and maverick. Fred designed two well-known antennas, the Slim Jim and the ZL Special. Both of these are now antenna standards. Fred was also an advocate of early British electronic music, inventing or modifying the tools he needed to make this adventurous music along the way. G2BCX was the quintessential tinkerer; a man who loved audio, radio, and the new possibilities for music being opened up by the careful application of capacitors.
As a radar technician in the armed forces during WWII Fred had the opportunity to develop his electrical aptitude and became a full blown engineer. After the war he found a spot working for the Kelvin Hughes company where he researched and developed marine radar devices. To this day Kelvin Hughes continues to create navigation and surveillance systems.
Fred was a man of strong ambition, and the day job in electronics wasn’t enough to keep him satisfied. As part of his side hustle he wrote articles for hobbyist magazines on radio and the new remote control models coming to market. The first of his 11 published books hit the shelves in 1954. When Amateur Tape Recording (ATR) magazine was launched in 1959 he joined the staff as technical editor and wrote on all kinds of topics connected to tape, electronics and hi-fi.
The slim jim antenna for which G2BCX remains famous among hams is itself a variation on the J-Pole. The J-pole is at the time of this writing a 110 year old design, first invented by Hans Beggerow in 1909 for use on Zeppelin airships. In that regard, the J-Pole, commonly made of copper, can also be considered a steampunk antenna. Trailed behind the airship, the J-Pole was made of a single element, one half wavelength long radiator with a quarter wave parallel tuning stub for the feedline. By 1936 this design had been refined into the J configuration and given the J Antenna name in 1943, now just called a J Pole.
Fred introduced his J-pole variant in 1978. He derived the name from its slim profile and the J type matching stub (J Integrated Matching). It has similar performance and characteristics to a simple or folded Half-wave antenna and identical to the traditional J-pole construction. Judd found the Slim Jim produces a lower takeoff angle and better electrical performance than a 5/8 wavelength ground plane antenna. Slim Jim antennas made from ladder transmission line use the existing parallel conductor for the folded dipole element.
The ZL special antenna came from another variant Judd made, this time on the 2-element horizontal phased array created by George Prichard ZL3MH –hence the name ZL Special in tribute to Prichard’s work. L.B. Cebik, W4RNL has written up a detailed analysis of this design at: http://www.antentop.org/w4rnl.001/mu5a.html.
It can be presumed that when Fred wasn’t at work, or on the air as a ham, he was engaged in another aspect of his electronics hobby: making circuits sing. He also wrote one of the first how-to books in the world for making electronic music in 1961, titled Electronic Music and Musique Concrete. It included circuit diagrams alongside practical do-it-yourself tips. (A copy of this tome is available from the Public Library of Cincinnati along with his Radio and Electronic Hobbies book.)
Around this time he also promoted the creation of electronic music via lectures and demonstrations at amateur tape recording clubs all around Britain. As an editor and writer for the Amateur Tape Recording magazine he had access to these clubs and lots of street cred within them. Fred started putting out 7” records of electronic music which were made available through the magazine. Judd was also the editor of Practical Electronics magazine. Chris Carter was an avid reader of both of these magazines and spent time building a lot of the circuits Judd published. Chris Carter went on to be a founding member of Throbbing Gristle, the first industrial music band. Chris continued to innovate in electronic music with his wife Cosey Fan Tutti as Chris & Cosey and latter Carter Tutti.
As any sci-fi movie or old-time radio show buff will know, one of the things electronic music is perfect for is making sound effects, and Fred became adept at making his own. Have you ever flipped around on the tube and come across the strange sci-fi puppet show Space Patrol? Broadcast in 1963 on the ITV network it was the first on British television show to have a composed electronic music soundtrack running throughout the whole series. Fred made those sounds himself using the techniques of tape manipulation, loops and tone generators in his home studio in London.
The Castle record label and its sister label Contrast issued a range of sound effects discs that he made in his studio, including 3 discs of electronic music. These tracks were later issued by library label Studio G, who specialized in providing stock music and sounds, on the Electronic Age album.
Fred also prototyped and built his own synthesizer. This simple voltage controlled, keyboard-operated unit was used to generate, shape and switch electronic sounds. The feat was small but impressive as it predated the Synket, Moog and Buchla synths.
Fred was also interested in the visualization of electronic sounds. One can imagine he knew his way around an oscilloscope and other test equipment. His tinkering in this area led to his Chromasonics system. By running a pulse generator and amplifier into a modified black and white tv that had a high speed color scanning wheel placed in front of the screen Judd was able to make trippy abstract patterns that moved in accordance with the sound input from oscillators or tape recordings. At the 1963 Audio Fair in London he demonstrated Chromasonics with much acclaim, but interest from electronics firm Stuzzi never made it to commercial development.
From the late 1970s Judd continued to operate as a ham from his home in Cantley, Norfolk. Towards the end of his life, he built several detailed reconstructions of early electrical devices including a Wimshurst machine and Edison phonograph. He was honoured by the University of East Anglia for constructing a working replica of apparatus used by Heinrich Hertz, but it seems that none of this equipment, the Chromasonics apparatus or his experimental music-making machinery has survived. He became a silent key in 1992.
In 2010 all of his remaining original quarter inch tapes have been cataloged and deposited with the British Library Sound Archive. In 2011 Ian Helliwell made a documentary on Judd called Practical ElectronicaA retrospective album gathering together as much of his experimental music as can be located, titled Electronics Without Tears was released by the Public Information label. It also contained an official biography of Judd written by Helliwell. It is available from their bandcamp page at: https://publicinformation.bandcamp.com/album/electronics-without-tears.
Here is a short bibliography of books by Fred C. Judd:
Radio control for model ships, boats and aircraft. London: Data publications, 1954.
Electronic music and musique concrète. London : N. Spearman, 1961.
Tape recording for everyone. Blackie, 1962.
Radio and electronic hobbies. London: Museum Press, 1963.
Circuits for audio and tape recording. Haymarket Press, 1966.
Electronics in music. London: Spearman, 1972.
Amateur radio. Newnes Technical Books, 1980.
Two-metre antenna handbook. Newnes Technical, 1980.
CB radio. Newnes Technical, 1982.
Radio wave propagation : (HF bands). London : Heinemann, 1987.
Electronics Without Tears, Public Information, Biography by Ian Helliwell
This article originally appeared in theJune 2019 issue of the Q-Fiver. (All the articles in the Radiophonic Laboratory series have appeared first in various issues of the Q-Fiver.)