valve, tube, thermionic, electron, triode, tetrode, pentode, power,
magic eye, tuning indicator, nixie, history, data, data sheet,
specification, amplifier, radio, octal, B9A, B7G, B4, IO, KT88, KT66,
12AX7, 12AY7, 12AT7, ECC81, ECC82, ECC83, 6L6, 6V6, EL34, EL84, EM34,
EM80, EM81, EM85,
Mullard, Cossor, GEC, Gold Lion, Marconi, Svetlana, Brimar, Ferranti,
RCA, Sylvania, GE,6202, amperex, arcturus, brimar, channelmaster,
colvern, cossor
dario, debanks, edicron, ediswan, ei, elpico, emi
emston, era, eratron, ever-ready, ferranti, ge, gec
heinz, kaufman, haltron, hivac, hrs, itt, jackson
lamba, lorenz, marconi, mazda, mullard, national, osram
philips, rank, raphone, raytheon, rca, rft, selectron
sovtek, standard, svetlana, sylvania, telefunken, tronix, tungsram
united, valvo, westinghouse, zaerix
6X4
Miniature indirectly heated full-wave
rectifier, equivalent to the
EZ90
.