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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
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sovtek, standard, svetlana, sylvania, telefunken, tronix, tungsram
united, valvo, westinghouse, zaerix

Here are Portable
Document Format (.pdf) scans of
a 1934 Triotron valve data leaflet.
TRIOTRON VALVES COMPARATIVE TABLE.
2 VOLT TYPES FOR BATTERY OPERATION.
| Mullard |
Marconi-Osram. |
Triotron. |
Cossor. |
Mazda. |
| PM12 |
S21 |
S207 |
215SG |
SG215 |
| PM12A |
S24 |
S215 |
220SG |
S215A |
| PM12M |
VS24 |
S208 |
220VSG |
S215VM |
| - |
H2 |
WD2 |
210RC |
H210 |
| PM1HL |
H210 |
HD2 |
210HF |
HL2 |
| PM2DX |
HL210 |
SD2 |
210Det |
HL2 |
| - |
L210 |
TD2 |
210LF |
L2 |
| PM2A |
P215 |
ZD2 |
215P |
P22A |
| PM2A |
LP2 |
YD2 |
220P |
P220 |
| - |
P2 |
UD2N |
230XP |
P240 |
| PM202 |
- |
E235 |
- |
- |
| PM22A |
PT2 |
P225 |
220PT |
Pen220A |
| PM2B |
B21 |
E220B |
240B |
220B |
4 VOLT TYPES FOR BATTERY OPERATION.
| Mullard |
Marconi-Osram. |
Triotron. |
Cossor. |
Mazda. |
| PM14 |
S410 |
S409 |
41SG |
- |
| PM3A |
H410 |
W420 |
410RC |
- |
| PM3 |
- |
H412 |
410HF |
- |
| PM4DX |
HL410 |
A430 |
410LF |
- |
| PM4 |
P410 |
E414 |
410P |
- |
| PM254 |
- |
E425 |
425XP |
P425 |
| PM24A |
PT425 |
P425 |
- |
- |
POWER AMPLIFIERS.
| Mullard |
Marconi-Osram. |
Triotron. |
Cossor. |
Mazda. |
| AC044 |
PX4 |
K435/10 |
4XP |
PP3/250 |
| D024 |
PX25 |
K480 |
- |
PP5/400 |
| DO60 |
DA60 |
K450/50 |
- |
- |
| PM24M |
- |
P435 |
PT41B |
- |
| PM24B |
PT25 |
P440 |
- |
- |
4 VOLT A.C. TYPES.
| Mullard |
Marconi-Osram. |
Triotron. |
Cossor. |
Mazda. |
| - |
- |
S415N |
- |
- |
| - |
MS4B |
S410N |
MSG/LA |
AC/SG |
| VP4 |
VMP4 |
S434N |
MVSPen |
- |
| SP4 |
MSP4 |
S435N |
MSPen |
- |
| 904V |
MH41 |
A440N |
41MH |
AC2/HL |
| 104V |
ML4 |
E430N |
- |
ACP |
| - |
- |
B430N |
- |
- |
| Pen/4V |
PT4 |
P440N |
MP/Pen |
AC/Pen |
20 VOLT D.C. TYPES.
| Mullard |
Marconi-Osram. |
Triotron. |
Cossor. |
Mazda. |
| SP20 |
- |
S2035N |
- |
- |
| VP20 |
- |
S2034N |
- |
- |
| HL20 |
- |
A2040N |
- |
- |
| - |
- |
E2020N |
- |
- |
| - |
- |
B2030N |
- |
- |
| - |
- |
P2020N |
- |
- |
RECTIFIERS.
| Mullard |
Marconi-Osram. |
Triotron. |
Cossor. |
Mazda. |
| DW2 |
U10 |
G470 |
506BU |
UU60/250 |
| DW3 or 4 |
U14 |
G4120 |
460BU |
UU120/500 |
| - |
- |
G4100 |
- |
- |
| - |
- |
G4150 |
- |
- |