Here's the EBAY info.......
1 x Telefunken EF732 microphone amp tube NOS milspec!
You are buying 1 pc. Telefunken Raytheon EF732 (5840, CV3929) premium tube, never used, made in the USA.
These tubes are made by Raytheon in 1974 and tested, labeled and boxed by Telefunken, Ulm in 1979 for for the Bundeswehr certified on the tube by a special mark “Falcon logo” near the bottom.
In original gov-type TFK boxes marked with "1 St. ELEKTRONENRŐHRE 5840 = EF732 CV3929 AEG-Telefunken, Ulm / Donau" and other info. Dates on boxes are 11/79.
The Premium Subminiature EF732 (5840, CV3929) tubes are made for longer life and lower microphonics due to it's rugged construction.
One of the best tubes for vintage and modern condenser microphones!
Used in Altec M20 (1960’s), Brauner (VMA, Valvet, Fantom), Mojave MA-200, Soundelux (U99, E250, U99S), Telefunken USA (Ela M14, Ela M260, RFT AK47)…The 5840/EF732 is one of the last valve types to be designed. The pentode uses lead out wires for direct soldering into circuit as the valve was considered to be as reliable as the rest of the components used in the design. These tipes are characterized by long life and stable peformance, and designed for service where severe conditions of high temperature, high altitude and mecanical shock or vibration are encountered. The flexible terminal leads may be soldered or welded directly to circuit components without the use of sockets.The 5840 features a pure-tungsten heater to give long life under conditions of frequent “on-off” switching. When used in on-off control applications, the tube will maintain its emission capabilities after long periods of operation under cutoff conditions.
Warranty: Unfortunately they are not tested (measured) because our tube tester B&K 747B can not measure such type of tubes. But to ensure our customers we guarantee money back 30 day warranty in case tubes do not poses satisfactorily parameters!