Valve Veneration
I am particularly fond of thermionic valves. These are the electronic components that paved the way for broadcast radio, television, radar and many other electronic applications. Many of the methods for analysis and design of electronic circuits developed in the valve era are still valuable for today's electronic circuits. So read on.
Admiring the glow
Once upon a time, all electronic devices used thermionic valves. Transistors, ICs and other semiconductors hadn't been invented yet. The charming thing about these thermionic valves is that they glow in the dark. Except for metal valves, the filaments or heaters generally show as a red-hot object in the core of the valve. The equipment usually produces an awesome lot of heat. So even if a piece of valve equipment is faulty, as long as the heaters glow, at least you get a feeling something is going on.
When I started my electronics hobby in the early seventies, I took apart old equipment and salvaged the parts to reuse them. That was a cheap way to find electronic components. Back in that time, friends and relatives gave me a lot of used radios and TV sets that became my main source of electronic components. As a result, I started with somewhat outdated electronics projects. During my study, I left this obsolete stuff behind. But not for good.
At the turn of the century, after more than a decade without electronic tinkering, my interest in electronics revived. Tubes and old display technology have become objects of nostalgia to me. So I keep a small collection of old radios and measurement equipment and from time to time I use old technologies in a project.
Things I built with valves
In the early seventies, I built a number of projects: a 6 W amplifier, an AC voltmeter, a 2*4 W stereo amplifier, a superregenerative VHF receiver, an FM receiver, a universal power supply. From these early years, only my regulated HV power supply has survived. Most of these projects have been lost long ago during removals and house-cleanings.
In 2001, I rebuilt a really nice two valve, two circuit regenerative receiver. In 2014 I took up a bigger project and built a Guitar amplifier combo.
Radio collection
I have a small collection of somewhat historical radios.
- Philips 836A radio from 1934/1935.
- A Philips 456A from 1936.
- A Philips 667A from 1937 (traded).
- Another Philips 667A, restored in 2005-2007.
- Third Philips 667A I fixed, for a
friend.
- An Isis model 127A from 1937.
- A Mende 315W radio from 1938 (traded).
- Philips 470U "Zonnetje" radio from 1938
- Waldorp 120 battery radio from 1940/41 (traded).
- A Philips 915X from 1940/41 (traded).
- A British Philips 170A/15 from 1946.
- British Wartime Civilian Receiver (1944)
- A Philips BX560A-02 from 1947.
- A Philips BX373A "Compass" bakelite radio from 1947.
- An Erres KY485 from 1948 (traded).
- A Philips BX480A from 1949.
- His Master's Voice 1101 radio, early fifties.
- His Master's Voice 1122 radio, early fifties (traded).
- An EAW AT Super 660 WK3, an East-German radio from about 1951 (traded).
- Bush DAC10 AC/DC radio, from about 1951.
- An Erres KY515 from 1952 (traded).
- Tesla Talisman 308U radio from 1953
- A Nordmende Fidelio (53) (traded)
- A Philips BX732A from 1954 (traded).
- An RCA Victor 4-Y-511 radiogram from the early fifties.
- A Philips HX347A radio/gramophone from 1954 or 1955 (traded for the RCA).
- An Erres KY552 portable valve radio from 1955.
- Philips B1X67U kitchen radio from 1956
- Philips B7X63A large luxury radio from around 1957
- Philips B5X74A plano radio from 1957
- Philips B4X82A-01 radio (traded)
- Erres KY585 radio (1959)
- Philips A5X83A AM/FM tuner (1960)
- Sharp UW-122 small table radio.
- Eddystone 840A communications receiver, Made in England in 1960.
- Eddystone 870A receiver, Made in England in 1961.
- Philips B5X14A Plano radio, Around 1961 (traded).
- Philips B7X14A luxury Plano, around 1961 (traded).
- Philips B1X42A AM/FM radio, around 1964 (traded).
- Bush VHF81 AM/FM AC/DC radio, around 1964.
- Philips B8X44A Plano radio with FM stereo, around 1964 (traded).
- RFT Stern Jalta 5360D DDR radio from 1965.
- MBLE BBO840 FM tuner from a kit, around 1965 (traded).
- Blaupunkt Stockholm FM stereo radio from 1966.
Amplifiers
Some amplifiers that I own or have fixed.
- A Geloso G215AN amplifier, from around 1960.
- A Bedrock 600 guitar combo, fixed for a friend.
Scopes and other equipment
So I own a few oscilloscopes, these wonderful instruments that make an electronics engineer or hobbyist feel like he's been a blind man who suddenly can see.
- A Philips GM5653, probably from 1949.
- A slightly newer Philips GM5653, probably from .. and working almost.
- A Philips GM5659 1 MHz lab scope from 1953
- A Philips GM5659-01 1 MHz lab scope from around 1957
- A Philips GM5603 high end scope, from 1961.
- A Philips GM5606, from the early sixties.
- A terrific Tektronix 545B, from around 1965 (traded).
- A simple Hameg HM107 scope, from 1965
Hey, even a transistorised analogue scope merits a place among valve equipment because it contains at least one valve, the CRT.
- A truly impressive Tektronix 568, from around 1968.
- An impressive 200MHz Tektronix 475 from the seventies, that I regularly use.
- A simple transistorised Heathkit IO4560, from the early seventies.
- A unique home-built Elektorscope
- A performing Tektronix 2235, from around 1983.
Scopes that I had the privilege to fix for friends:
- A Heathkit IO-20 ignition analyser, from 1960.
- A Hameg HM207 scope, from 1973.
- A Telequipment D83 scope.
Valve measuring equipment
I also have some other measuring equipment with valves:
- A Philips GM2882 RF generator from around 1945, not working.
- A slightly more recent working Philips GM2882 RF generator (traded).
- A Philips GM2885 Calibrating oscillator (1949)
- A Philips GM6004/02 diode voltmeter, about 1951.
- Another Philips GM6004/02 diode voltmeter, about 1951.
- A Philips GM7635/01 valve multimeter, from 1953.
- A Philips GM2317 LF generator, from 1953.
- A Philips GM2883 RF generator from 1954.
- A Philips GM2886 RF sweep generator from 1955.
- Two Heathkit V-7A Valve
Voltmeters
- A IM-11D Valve Voltmeter
and a wreck
- A Paco V-70 Valve
Voltmeter
- A Philips GM6012 AC valve voltmeter from around 1960.
- A Heathkit IG-102 RF generator, around 1960.
- A Taylor model 67A RF and AF generator, from the early sixties (traded)
- A Philips PM5100 LF generator from 1963.
- A NordMende UW342 sweep generator
from the early sixties
- A Philips PM532O signal generator with AM and FM (1962-1966).
- A Philips PM5321 signal generator with AM and FM (1966-1970).
And I have two tube testers in my collection:
