Common type Europe tube/semicond. According to our profound investigations and tests, the tubes ECH81 and ECH83 are equal - not even tested differently, but only stamped differently. They naturally show different values for a different usage (volts anode). See this forum article here about that. More ...

The ECH81 triode heptode was designed in 1954 for the role of frequency changer (mixer) in superhet receivers for AM reception. The ECH81 acting as oscillator and mixer for AM and the heptode being the first IF amplifier on FM. The two valve sections share a common cathode.

2018年11月17日 · ech81就是6u1，后面两个是电视机里同步分离和变周用的，国外很常见，经常能看到成百上千只的，除了ech81能修修收音机外用处不大 回复 支持 反对 使用道具 举报

2007年4月9日 · 6u1是50年代才开发出来的专用混频管，欧洲编号：ech81，是一只优秀的混频管，只可惜当时已处于电子管的黄昏时期了， 用6u1混频，与6a2相比，无论在增益、信噪比、稳定度大大好于6a2，

2020年1月5日 · V2 (ech81) triode section does have a dual function on this schematic. On most tube radios, this tube only works as frequency changer (mixer/oscillator). On this radiogram, it also works as additional audio frequency amplifier for the PU input.

2021年7月20日 · ECH81 also works at low voltage. According to market needs, this tube was either stamped ECH81 and sold for tube radio use or ECH83 and sold as low voltage car radio tube. The UCH81 is maybe more useful for audio purposes than …

ECH81 page sheet date 1 1 1969.12 2 2 1969.01 3 3 1969.01 4 4 1969.01 5 5 1969.01 6 6 1969.01 7 FP 1999.08.15

2024年10月20日 · Being a triode-heptode vacuum tube, the Amalgamated Wireless Valve ECH81 served for fulfilling two distinct roles-at once-the local oscillator and the frequency mixer. Combining both these functions in one valve actually allowed building radios that were smaller and less expensive.

2019年1月28日 · One of the major electronic products of the XXth century was the radio, and that is what I will be looking at next - the tubes of the common radio receiver. In this video I look a common signal...

2009年5月11日 · 欧洲收音机中有代表性的德律风根收音机用管常见配置：1 x ECC85——FM接收1 x ECH81——变频2x EF89——中放1 x EABC80——检波鉴频低放1 x EC92——倒相2 x E ...