List of historic valves in the ase-museoedelpro collection
Here is a list of some historic valves in the collection, including a survey of early valves, up to mid 1930s, power and transmitting tubes, VHF and UHF types, tubes designed for radar application and several very early prototypes designed and built during the British radar development, magnetrons, klystrons, and conventional gridded types. There are also more recent types added because of their operating principles or even because they are evolutions of early types.
The ASE-Museoedelpro collection includes several hundred types of valves. This is only a partial list that will be updated as other valves cards are ready. Some links could still left open, please access from the Virtual Museum selection. *** Last update: October 2025.
1B42	Mercury spark gap, radar pulse modulator. Western Electric Mercury pool was used to continually renew the surface of the negative electrode. 200 A at 6 µs pulses. Description in the BSTJ Vol. 25, Oct. 1946 and in Glasoe, Pulse Generators, Rad Lab Series, Vol. 5.		**°
2H21	Phasitron' FM modulator, General Electric, 1950s. Also available the 5593, different parameters.
2J21 / 2J21A	Magnetron, very early unstrapped X-band, 1941. Westinghouse. Rare, superseded from 1942 by the WE 725A.		*
2J22 ÷ 2J29	Family of S-band magnetrons. 250 kW typical pulses
2J36	12-vane X-band magnetron. Still unstrapped, it was released early in 1942, being registered to Raytheon only after the war, in October 1945. Used in the AN/MPN-1 ground controlled precision approach radar system.
2J38 / 2J39	Fixed frequency low power magnetrons operating at 3.300 MHz. Integral magnet. Coaxial output. Registered to Raytheon in October 1945, RMA record 445.
2J51A	Packaged magnetron, mechanically tunable from 8.5 to 9.6 GHz. 20 to 70 kW peak power by moving one to four magnetic shunts. Western Electric. Full description given in 1946 in the Bell System Technical Journal.
2J55 / 2J56	Fixed frequency variants of the packaged 2J51A
2J61(A)/ 2J62(A)	Mechanically tunable S-band magnetrons with overlapping frequency coverage. Designed to replace the family of fixed frequency types 706AY to 706GY. Registered to Raytheon in October 1945, RMA record No. 445.
2K33 (A,B)	Raytheon K-band reflex klystron. Derived from early prototypes of VX302 developed in UK at the Clarendon Laboratory from 1941. In the UK the devvelopment of the 24 GHz radar was abandoned due to the excessive attenuation caused by water vapor.
2K50	K-band reflex klystron developed in 1944 by Western Electric. Thermally tuned by electronic bombardment. Waveguide flange.
3B600	Power triode intended for electro-medical applications. Fivre		*
3C27(B)/3C37	UHF power triode, National Union proposed its own variants of the British milli-micropup family. Flying wires replaced by coaxial connector and in the 3C37 a finned radiator was added to the grid rod, for better pulse operation when the grid was heavily driven positive.
3F3-TRX	Forced-air cooledn 3 kW transmitting triode. Fivre		*
3F20-TA	Transmitting triode, external radiator or water jacket.  22 kW. Fivre		*
3F22-TA	Transmitting triode, compact folded anode variant of the 3F20-TA. Fivre		*
4C27	UHF transmitting triode, 'micropup' style. U.S. equivalent to British CV92, CV199, NT99 and to Canadian REL 7
4C28	UHF transmitting triode, 'micropup' style. RCA variant of the 4C27, for the SHORAN navigation system.
4C29	UHF transmitting triode, 'micropup' style. Flying leads replaced by a coaxial connector. Registered in the U.S. by Canadian REL. Manufactured by Canadian Rogers and by Central Sales in the U.S.
4J52 (A)	Packaged X-band magnetron. RMA registration reserved to Western Electric in November 1944, registered only after the war, in October 1948. RMA record No. 703.
4J57	Packaged magnetron operating in the C-band. 250 kW. Registered to Raytheon in 1946.
5J26	600 kW magnetron, mechanically tunable from 1.220 to 1.350 MHz. Intended to replate the entire family of fixed frequency types from 4J21 to 4J30. Western Electric during WWII
5J29	Split anode CW magnetron, liquid cooled. General Electric developmental code ZP579. It was designed to operate from 350 to 770 MHz in the radar jammer AN/APT-4
5J30	Split anode CW magnetron, liquid cooled. General Electric developmental code ZP590. It was designed to operate from 150 to 385 MHz in the radar jammer AN/APT-4.
5J32	Split anode CW magnetron, liquid cooled. Coaxial copper tubes for liquid cooling of the anode blocks. General Electric. It was designed to operate from 350 to 750 MHz in the radar jammer AN/APT-4.
5J33	Split anode CW magnetron, liquid cooled. Three anode segments, the central one connected to the mid point of the line.  General Electric. It was designed to operate from 750 to 1.150 MHz in the radar jammer AN/APT-4.
6C21	Eimac power triode derived from the 1000T. Intended as power pulse modulator
8P1	Ultra hi-rel pentode designed by British GPO to operate in submarine cable repeaters, system life expectancy exceeding 20 years.  Quite late, 1962, and extremely rare. Only evaluation prototypes made before submarine cables were replaced by communication satellites.		*****
10AL1	Reflex klystron, British early experimental prototype in order to improve the 'Sutton tube'. It shows a flat repeller, such as in the WE 707A and close interaction with the electron beam by means of meshes of molybdenum ribbon on the resonator ends. This solution will be later adopted in the new S-band klystron family, as in the CV238. Second half of 1941.		*****
10E501 / CV11	Early reflex klystron, designed by Robert Sutton in 1940 as local oscillator for microwave radar receivers. Also known as 'Sutton tube'. The collection also includes an unbased prototype. This and the unbased one are the only known samples of the original 'Sutton tube'. ** September 1940 onwards.		*****
35T- Vacuum Gauge	Eimac ionization vacuum gauge, derived from 35T transmitting triode. Likely used in the evacuation system of the 'resnatron' 1 MW tetrode.		*
53A	Eimac VHF transmitting triode. Smaller than other similar triodes, 227, 327 and VT-127. Probably used in the transmitter of ASB airborne radar
175HQ	Ultra high rel amplifier for submarine cables designed by Bell Telephone. Used in the Avana-Key West and in the TAT-1 transatlantic cables. Designed for system life exceeding 20 years! June 1941 onwards. ***Extremely rare		*****
356A / 356B	VHF power triode, derived from the 100TH. Used in the modulator of the early CXAS radar. The gridless variant was proposed as 705A, high-voltage rectifier. Western Electric and British STC.		**
357A / 357B	VHF transmitting triode. Western Electric and later Machlett		**
364A	VHF all-glass transmitting triode. Western Electric. Pre-WWII, used in WE radio links. According to Ludwell Sibley, used since 1939 in the Massachusetts coasts to Cape Charles and later in the Cheasepeak Bay radio links. *** Very rare		****
402A	Early Western Electric linear-beam klystron amplifier. This is the only one gone into small production of the many experimental types made at Bell Labs around 1940. *Rare!
410 Westinghouse	Early power klystron developed by the Varian brothers and gone into limited production in the US around 1940. 10 W out at 3 GHz. Complete with Type 10 tuner. ** Very rare!		*****
455A	Ultra high-rel amplifier for submarine cables. Designed to operate 20 years with no failure, in order to replace the 175HQ for the new SD transoceanic system. The tubes were built by Weswtern Electric. Each tube was aged for 5.000 hours. **** Extremely rare!		*****
527A / PL-185	VHF power triode used as radar oscillator or modulator. Four tubes in the ring oscillator of SK-1M set gave 1 MW at 225 MHz. Eimac was second sourced by Penta Labs with its code PL-185.		*
700B	The 700A-D was the first cavity magnetron designed by Westren Electric after the Tizard Mission revealed progress with the E1189 magnetron. Early 1941. *** Very rare!		*****
701A	Power tetrode proposed as pulse modulator. Large glass bulb containing four electrode sets of the 350A with common molybdenum plate. Western Electric, 1941.
706A-C (Y)	Early Western Electric family of S-band magnetrons. Introduced only after the six-cavity 700, the unstrapped 706 was available in three frequency variants, A to C. The strapped version, Y suffix, included more frequency variants, from A to G.
714A(Y)	Western Electric early magnetron, similar to 706A but t operating at 3.300 MHz.
720CY	1 MW S-band WE magnetron. To increase the emission, the cathode and obviously the anode length were doubled with respect to the dimension of the 714 family		**
723A (A/B)	In the US the design of the 723A (in the photo), the first reflex klystron for the receiver of the X-band radar, started at WE in the first half of 1941. The resonator was moved into the evacuated metal envelope and the tuning was possible from the outside by flexing the top wall. Tuning range was quite narrow, around 9.375 MHz. Soon later, in the 723A/B, the tuner struts were lengthened to extend the frequency range.
725A	The X-band strapped magnetron 725A was designed at Western Electric to replace the 2J21. During WWII its production exceeded 250.000 units, more than 90.000 of which supplied to the British Empire under the Lend-Lease law.
728DY	200 kW UHF magnetron family, A to J suffixes covering from 900 to 970 MHz.		*
730A	The Western Electric 730A was similar to the 725A above, with the WG flange rotated 90 degrees.
880 / GL-880	Folded anode 20 kW transmitting triode requiring external water jacket. The very compact arrangement of the electrodes also offers improved frequency performance. An excellent demonstrator of glass-to-copper welding technology.		*
891 / 891R	The rated power of the water-cooled 891 triode was 7 kW. The  891R with finned radiator was rated at 4 kW with forced-air cooling. *** This sample, made by Italian Fivre, survived the shipping to us despite its mass of over 20 kg.***		**
3036D	LMT UHF retarding-field triode for Barkhausen-Kurz oscillator. Early in the 1930s this was the simplest way to generate frequencies above 100 MHz. Unfortunately the obtainable power was very low, in the order of a few milliwatts.		****
6090	Electrostatic beam switch/multiplexer. National Union. *Measurements, rare!
4316A	British STC equivalent for the WE 316A 'doorknob' style UHF triode. The 316A was used in the early eperiments of AI radar, as reported by Bowen. Due to the complex manufacturing process and to the introduction of better performing types by GEC, in England all dooknob tubes entered into the black list of the Inter-Service Technical Valve Committee issued in June 1941.
5531	Transmitting power triode, forced-air cooled. 10 kW power dissipation. Registered to Western Electric in february 1949, RMA release 734.
5586	Pulse magnetron tunable from 2.7 to 2.9 GHz. Replaced the family of fixed frequency types 4J31 to 4J35. 800 kW typical output power.
5593	General Electric 'Phasitron' FM modulator tube. The principle was first introduced by Robert Adler at Zenth Radio in January 1946. Similar to GE 2H21, different operating parameters.
5680 / 7C23	2.5 kW power triode, finned radiator also intended for pulsed operation with 35 A peak emission.
6090	Electrostatic beam switch multiplexer. National Union
6230 / QK299A	Mechanically tunable magnetron, integral magnet, wg out. Used in the active guidance of the Nike-Ajax and in the AN/UPW-1 X-band data link. Raytheon.
6324	25-line magnetically focused beam switch/multiplexer. National Union *Measurements, rare!
6344A / QK235	Tunable magnetron, integral magnet. 260 kW typical from 5.450 to 5.825 MHz.
6410 / QK338	High power packaged magnetron. 5 MW pulses at 2.750 to 2.860 MHz. This sample, still in its factory shipping crate, was manufactured by ElTel.
6896 / 1855	RCA 'Graphecon' scan converter tube. Dual gun tube, basically designed to convert ppi images in a format compatible with raster video monitors
7003 / ML-7003	Screened grid power triode intended to operate as pulse modulator up to 2 MW. Grid wires are protected from direct strikes of electrons when grid is heavily driven positive during pulses.		*
7503	Low power X-band magnetron for beacon application. 200 W peak output power.
A-103A	Experimental split-anode magnetron w/internal loop, probably proposed by RCA in 1941 to operate as local oscillator at 3 GHz.  Later registered as 3J35, no known use.		*
A1396B	RCA experimental beam-deflection amplifier, probably made in the development of the 1636 UHF mixer Experimental, very rare!
ACT25 / CV436	In 1943 GEC introduced the CV288 triode for CW and pulse operation up to 600 MHz. After the war the design was proposed again in the ACT25 wide band UHF power amplifier		*
AT50	50W 'Three-foot' style early transmitting triode. Early 1920s		*
C100A	Quite unique external-grid oscillator designed by Amperex for Collins around the mid thirties. This kind of non-conventional oscillator had been patented in 1915 by Dr. Robert Goddard, the scientist known for his works on rockets.		****
C100D	Negative resistance oscillator, designed by Amperex for Collins as improved variant of the C100A		****
C31007C13	RCA experimental 10-stage photomultiplier. No data
Catkin-Prototype	GEC experimental 'Catkin' prototype with radiator. Derived fro the CAT transmitting power tubes, the smaller Catkin family retained the external copper anode sealed to the bottom glass bulb		****
CG-1162 / VT-14	General Electric pliotron, early transmitting triode, introduced during the Great War. Two variants available with two or with four plate supporting strips.		*
CV8 / E1248	Coaxial diode, micropup style, designed to operate as T/R switch in the duplexer of the Naval Type 270B radar. GEC, 1941		**
CV14	Silica' transmitting triode designed to operate in VHF RDF sets. Operation proved to be marginal above 150 MHz and micropup triodes were preferred About 1941. *** Rare		****
CV15	Micropup' style transmitting triode, conduction-cooled. Intended to operate in the VHF region, up to 300 MHz		*
CV22	Mercury thyratron designed for high-power pulser, 50 A at 20 kV. BTH		*
CV55 / CV155 / CV178	Milli-micropup power triodes, useful for CW or pulsed operation up to 1.200 MHz. In radar applications two CV155s generated 40 kW pulses at 1.200 MHz. Developed at GEC from the late 1939 to 1940.
CV56(*)	Early strapped variant of NT98, used among the others in the Type 271Q Naval radar. Soon later supplied in four frequency variants, A to D suffixes from the 1943 production. Frequency variants available, idntified for their suffix A to D.		***
CV58 / CV258	Planar diode, UHF mixer
CV64	Strapped variant of the E1198/CV38 magnetron. Developed by BTH, it was used in the H2S transmitter. See also the Canadian REL 3C and the German copy LMS 10.		****
CV69	The first strapped cavity magnetron capable of operation at 1 MW input power. Used in the Type 271 Naval radar set. CV69A to D were later relisted as CV1475, CV1476, CV1477 and CV 1478		***
CV76	High power variant of CV56 operating with higher magnetic field. 25 kV at 40A input pulses. Used since early 1943 in the Type 277 early warning radar.		***
CV87 / KRN2	Early X-band reflex klystron using the harmonic resonator proposed by Blumlein at EMI in close collaboration with the Clarendon Laboratory. First samples were available by March 1941.		***
CV94 / DS103	Coaxial diode, T/R switch, probably designed to replace the CV8. Used in the Naval Type 960 radar, 450 kW. 100 A peak cathode emission. About 1945.		*
CV109 / 9PK5	First British power klystron, Only few experimental samples made in 1940, being outperformed by the E1189 cavity magnetron. 150 W at 10 cm. *** Extremely rare!!!		*****
CV150 / PK150	10 cm power klystron designed by EMI in 1941 for the transmitter TR 3539 for airborne radar set. 30 kW peak power. The design of this klystron was requested by Winston Churchill himself for the radar sets of aircraft on missions on the continent, thus preventing the enemy could capture the cavity magnetron. *** Exremely rare!!!		*****
CV160	1 MW S-band high power magnetron. Coaxial output. 1944		***
CV192	High-power variant of the CV64, to be used in pressurized execution of the H2S airborne radar. Conduction cooled from the heavy metal block.		****
CV208 / E1487	GEC early strapped X-band magnetron The collection includes two samples, one with wg adapter/mount and duoble heater stem, the second one with single stem.		*****
CV209 / MX57	BTH early strapped X-band magnetron. Mechanically and electrically compatible with GEC CV206		*****
CV214 / E1531	GEC variant of CV208 with waveguide flange and protective glass boot.		**
CV230	Heil tube oscillator. Probably proposed as local oscillator for the 10 cm radar receiver. *** Exremely rare!!!		****
CV240 / E1495	GEC high-power triode, micropup style. 125 A emission at 15 kV max anode voltage. 100 MHz. Design started in April 1944.		****
CV322	British reflex klystron, functionally equivalent to WE 723A/B. The CV322 title applies to the same 723A/B Probably just few prototype samples made in the second half of 1941, waiting for the release of the WE 723A		*
CV381 / BT85	BTH hydrogen filled thyratron. 90 A at 10 kV. 2500 pps max pulse repetition rate. The sample was in service on the HMS Trenchant.
CV1025 / VT25	Transmitting triode with L4 base. 36 W plate power. Also known as DET25.
CV1030 / VT30	Early MOV 250 W transmitting triode. Introduced as T250, it was accepted by British Post Office as VT30 and by Royal Air Force as 10E/8738. Later, different codes were unified under the title CV1030. 1922 - Rare		***
CV1031 / VT31	Early British 250 W transmitting tetrode.		**
CV1090 / E1046	First 'micropup' VHF transmitting triode, GEC design code E1046. Also known as VT90. Introduced in 1939 with the early AI and ASV radar sets, it was produced through WWII in several countries, US, Canada, Australia, with different codes. One of the most popular VHF power triode in WWII.		*
CV1098 / E960T / REL5 / VT98	VHF transmitting triode for pulse operation. Derived from MOV ACT10 early TV transmitting triode.Used in the CHL radar system. Also made for REL by Canadian Westinghouse for the Panama Channel surveillance system. 1939 variant of the 1938 E960/VT58, with thoriated-tungsten filament.
CV1479 ÷ CV1482	Family of magnetron tubes which replace CV79A to CV79D frequency selections.
CV1483 ÷ CV1486	High power magnetron fsmily, replacement for CV99A to CV99D. 400 kW.
CV2222 / CVX2222	Power triode capable of operation up to 1.5 GHz. Probably evolved from the wartime CV288.
CV2341	Marconi coaxial saturated diode, noise generator. *Measurements, rare!
CW10	Osram early split-anode magnetron. About 1936, rare!		****
D-75910	Western Electric vacuum ionization gauge *Measurements, rare!
D-75912	Western Electric vacuum ionization gauge *Measurements, rare!
DS323	Lorenz UHF power triode. Early type, about 1939, replaced by RD12Tf from 1941. Rare!!!		****
DV27	Heil tube oscillator, 3 GHz Only experimental samples, very rare!		****
DV57	Heil tube oscillator, 10 GHz Only experimental samples, very rare!		*****
E880 / NT75 proto #1	Megaw's split-anode four-segment magnetron built during the development of the E880/NT75 for the transmitter of a ship-to-ship secure communication system commissioned by the Admiralty. About 1937, coming from the today dispersed GEC collection. Megaw's experimental prototype, 1936/1937		*****    Megaw's notes on this magnetron can be read here.
E880 / NT75 proto #2	Split-anode four-segment magnetron built during the development of the E880/NT75. Similar to the previous one, with small differences in the end connections of the filamentary cathode. About 1937, same source as for the previous one. Megaw's experimental prototype, 1936/1937		*****
E880 / NT75 proto #3	This sample has the same four-segmant split-anode design of the other two E880 prototypes but it is fitted with an additional grid wire for direct modulation of the carrier. Megaw's experimental prototype, 1936/1937 *** ABSOLUTELY UNIQUE ***		*****
E1189_Early_Prototype ********************	This is the very early prototype of the eight-cavity E1189 magnetron. It was the first one of a lot of four 8-segment units to operate on the bench, while connected to the vacuum pump at the end of July 1940. It was designed and used by Megaw for laboratory test and life endurance evaluation of the oxide-coated cathode. The third one of the lot was the E1189 No. 12 brought to America by the Tizard Mission. *** ABSOLUTELY VERY UNIQUE ***		to an article
ET1	MOV electrometer triode, 1936 - 1937 *Measurements, rare!		****
ET630 / QK630	Stabilotron', crossed-field 'Amplitron' with external cavity. Made by ElTel, equivalent to the Raytheon QK630. Rare sample of cross-field amplifier, made in Palermo, Italy to Raytheon design.
GEC_Experimental #1	Very early split-anode magnetron, verical structure supported by glass rods. Probably made around 1932-1933 as prototype of the NT52 magnetron with silica bulb. VERY UNIQUE SAMPLE OF POWER MAGNETRON FROM EARLY 1930s!		*****
GEC_Experimental #2	Early high-frequency magnetron. 1934 or before. Not sure but its design could be the E552. Megaw's experimental sample!		*****
GEC_Experimental #3	Early gridded magnetron prototype. Vertical structure, spiral wound modulating grid. 1935 ??? Megaw's experimental gridded sample!		*****
GEC_Experimental #4	Split-anode experimental gridded magnetron designed by Megaw for a ship-to-ship secure communication system. The bi-filar grid was added for investigating the direct modulation of the RF signal. About 1937, coming from the today dispersed GEC collection, its photo appearing in the book 'The GEC Research Laboratories, 1919 - 1984. Megaw's experimental gridded sample!		*****
GEC_Experimental #5	Split-anode experimental magnetron designed by Eric Megaw to investigate operation in the microwave region. Believed to operate at 3 GHz or more. Coming from the today dispersed GEC Research Laboratories collection. Megaw's experimental sample!		*****
German_magnetron_unknown	German split-anode magnetron with built-in back-loop. Believed to be a Siemens magnetron made in 1943 for the Roderich jammer, according to a design made in 1937 at the Reichpost Developmental Department. Kindly supplied by Karl-Heinz Gollmann. *** Exceptionally rare German magnetron!		*****
LBS-1	Electrostatic deflection 10-position beam switch tube. Announced in 1955 by National Union. *Measurements, rare!		***
LG76 = CV76	German copy of the CV76 T/R switch. The sample was probaly used in the ealy experiments on the proper gas mixture to protect the diode mixer, since it has a small hole to the glass wall. Exceptionally rare!
LMS10	German strapped 8-cavity magnetron operating in the 10-cm band. Copy of the British CV64 after the capture of a H2S radar in the crash of a British bomber near to Rotterdam early in 1943. About 1.000 units made, most of which damaged in the crashes of German fighters as for our sample. *** Very rare, about 1.000 units made in WWII!		*****
LMS12	X-band German cavity magnetron built to an almost unknown Telefunken design. AKA LM566/3 Believed to be the only sample today survived, it was stored somewhere at the US War Department. ***Ultra rare, about 50 made!!!		*****
LMS13	18 GHz variant of the LMS12. Still in the pre-production or sampling status before the end of WWII. Almost certainly this is the only sample today survived, coming from a basement of the US War Department. *** Quite unique sample!		*****
M-16 experimental	This CSF 12-segment M-16 magnetron is one of the two experimental 12-segment samples designed by Henri Gutton at CSF for his friend Megaw and brought to GEC in May 1940 by Maurice Ponte. It was used by Megaw to test the oxide-coated cathode before switching to this solution for the E1189 No.2 cavity magnetron. It fully shows signs of the severe use described by Megaw in his 1946 paper on the development steps of the E1189 magnetron. *** The only one of two samples made in 1940!!!		*****
Magnetic field sensor CRT	CRT designed in 1938 at RCA, Harrison to evaluate intensity and direction of magnetic fields. No data, but it was described in Electronics, June 1938. *Measurements, rare!		*
MD10/1900	Brown-Boveri 'Turbator', CW magnetron deisgned for UHF communication links. 10 to 15 W at 1.900 MHz.
MD10/2000	Brown-Boveri 'Turbator', CW magnetron deisgned for UHF communication links. 10 to 15 W at 2.000 MHz.
MD500/2400	Brown-Boveri 'Turbator', CW magnetron probably deisgned for RF heating. No data found: the code indicates a power of 500 W but certainly such a value could not be continuous, rather we must think to short bursts.
MF150/2400	Brown Boveri 'Turbator', single-sided CW magnetron. The basic design joins an eight-segment interdigital magnetron with a surrounding cavity which terminates the external resonating line. Introduced in 1947, this CW magnetron could give about 150 W at 2400 MHz.
MT9	Marconi 600 W power transmitting triode. 1925, very rare!		*
NT39 / CV1222	75 W external anode transmitting triode. Was used in the long range Wireless Set No. 23
NT41A	Silica transmitting triode, early metric RDF transmitters. About 1935-1936, very rare!		****
NT45A / CV1226	Silica transmitting triode, HF communication. Rare!		****
NT46R	Silica transmitting triode, used in early metric RDF transmitters. About 1935-1936, rare!		****
NT57D	Silica valve' transmitting triode designed to operate in the early British radar sets. 1937 *** Rare!		***
NT57T	Silica valve' transmitting triode designed to operate in the early British radar sets. The T suffix indicates the variant with thoriated-tungsten emitter. 1939 ***Rare!		***
NT63A / CV1239	Silica transmitting pentode ***Rare!		**
NT86 / CV1248	High-power silica transmitting triode. Used to generate 1 MW pulses in RDF sets ***Very rare!		****
NT98 / E1198	Early 10 cm cavity magnetron, Admiralty reference code for the E1189 GEC design. Sometimes marked with the Admiralty Pattern AP W2510. The first cavity magnetron. Rare!		****
NT100	Power terrode, 'catkin' style with finned radiator. Intended as pulse modulator for early unstrapped cavity magnetrons, such as E1189, REL 3C or REL 3D. Replaced by CV85 trigatron from the end of 1942. *Very early pulse modulator, rare!		**
QS5033	Strapped magnetronlaboratory prototype. Probably made at Birmingham by the Sayer's group in 1941, ***Experimental sample!		*****
QK174C	CW FM magnetron. Frequency modulation is achieved by means of six auxiliary electron beams directed to the resonators. Its principle was first proposed at MIT and then explored in depth in Proceedings of IRE, July 1947. The Raytheon QK174A was advertised in Electronics in February 1949, while the QK174C was advertisend in March 1953. ***Very intriguing operation! Rare!		****
QK328	Raytheon beam-deflection analog multiplier *Measurements, rare!		***
QK680	Raytheon 'Amplitron', crossed field magnetron amplifier ***Rare!		**
QK707A	Water-cooled CW magnetron. It was intended for microwave ranges. This sample probably dating around 1960 was built in Italy by ELSI, Elettronica Sicula, at the time owned by Raytheon, with a fully qualified production line. ***Likely used in the microwave ovens delivered to Autogrill Pavesi service stations in the late 1950s		***
R1001 / 3C36	R1001 was being developed by National Union at the end of WWII for UHF power application. The 3C36 registration code was assigned in February 1946. According to Ludwell Sibley there was no known production This sample probably comes from the collection of the late Rodney Burman. Very rare, only evaluation samples!		****
RD2Me	Split-anode, four-segment magnetron, designed in 1943 by Telefunken for the 9 cm Roderich radar jammer. ***Very rare, late 1943!		**
RD12Tf	UHF power triode made by German Lorenz for pulse applications up to 600 MHz. Two used in the transmitter of the FuG 200 Hoentweil radar, generating 30 kW pulses. Evolved fron the DS323. WWII German radar technology!		*
REL 3C / E1198	Early Canadian copy of the GEC E1198. Made by Northern Electric it was the frequency variant of the GEC E1189, intended for airborne radar sets. Fully equivalent to CV38. *Canadian early magnetron, 1941		***
REL 3D / E1189	Early Canadian copy of the GEC E1189. Made by Northern Electric it was used in some radar sets designed and built by REL, such as the naval RX/C and the Canadian GL3. 1941 *Canadian early magnetron, 1941		***
RM4025	Quasi-experimental split-anode magnetron with internal resonator made by Siemens around 1944 or 1945. 10 GHz output frequency. Very rare!		****
RS19	Very early Telefunken transmitting triode, about 1919.		**
RS394	UHF power triode used in the transmitter of FuG202 Lichtestein radar since 1941. WWII German radar technology!
RT323	Japanese VHF transmitting triode. Designed by Toshiba for the Tachi No.7 radar set. Instead of copper radiators of the English and American tubes, this tube has a light alloy radiator, maybe aluminum. WWII Japanese radar technology *Very rare!		****
TAL12-35	Large forced-air cooled transmitting triode made by Philips. In this valve various technologies used in the combined processing of copper and glass can be visually appreciated.		***
TS1 / TS1a	GEMA UHF transmitting triodes derived from WE 316. The base connection of TS1a is reversed. WWII German radar technology.
TS5	GEMA VHF triode, ruggedized variant of WE 304A or of 8304 WWII German radar technology. Rare!		*
TS6	UHF triode, 'giant doorknob' style. Two were used in the transmitter of the GEMA marine radar Seetakt, giving 8 kW pulses. WWII German radar technology. Rare!		**
TS41	VHF transmitting triode deigned for GE$MA radar sets. WWII German radar technology. Rare!		*
TS60	UHF triode, 'ship in the bottle' style, 1943 onwards. Used in the transmitter of Wasserman and Jagdschloss radar systems. 100 to 150 kW pulse power. WWII German radar technology.Ultra rare!
T-310	Japanese UHF power triode. It recalls the Telefunken LS180 used in the Wurzburg radar sets. Na data but likely this tube was designed for the Tachi 24 equivalent to the German radar. *WWII Japanese radar. Ultra rare!		*****
TWS-1	Early GEC S-band TWT, 1960. Beleved to be the first TWT listed by GEC		***
VT-158 Zahl Tube	Actually the VT-158 is a power UHF oscillator, using four triodes in a parallel/push-pull configuration, entirelly sealed in a compact glass bulb. Designed between 1942 and 1943 by Dr. Zahl for the AN/TPS-3 radar.		*****
VT30 / 10E8738	Early MOV 250 W transmitting triode. Introduced as T250, it was accepted by British Post Office as VT30 and by Royal Air Force as 10E/8738. Latei it was titled as CV1030. *Early 1920s. Rare!		**
VX302	K-BandClarendon Experimental klystron. The design was abandoned in England but it was completed by Raytheon, originating the 2K33 and its frequency variants. °Clarendon experimental sample!
VX6122 / 19H12	Quasi-experimental power damping diode intended for use in radar modulators. Eight diode systems in parallel, all welded around a molybdenum cylinder. The bulb shape recalls the one of the 833 transmitting triode.		***
XL7900	Actually not a vacuum tube but a Philips vibrating capacitor, intended as low-noise modulator for extremely feeble signals. It replaced electro-mechanic choppers, making it possible to measure currents in the order of femtoamperes, as low as 500 electrons per second! *Measurements, rare!		**