> European tubes are easy to evaluate in that respect because the letter codes > designate what's inside. I remember the EABC80 (not sure that's the correct
EABC80 _is_ the correct number. It is a triple diode triode. The number decodes as follows : E : 6.3V heater A : diode B : double diode (so a total of 3 diodes) C: triode 8 : B9A (noval) base There is also the (more common) UABC80 (with a 100mA heater for series string use) and PABC80 (least common, with a 300mA heater for series string operation). > number), which is a diode plus double-diode plus triode. Intended > application, > if I remember right, was FM detector (discriminator, double diode), AGC > detector > (single diode) and audio preamp (triode). More often it was used in AM/FM radios. 2 diodes for the FM detector and one for the AM detector and AGC. And the audio amplifier triode. -tony