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This table was extracted from "Amateur Wireless" No 122, 4th. of October, 1924.
Maker | Type of Valve | Filament Voltage | Filament Amperes | H.T. Voltage | Purpose |
---|---|---|---|---|---|
B.T.H. | B3 | 2.0 | 0.35 | 20-80 | General |
B4 | 6.0 | 0.25 | 40-100 | Detector and Low Frequency | |
B5 | 2.5-3 | 0.06 | 20-80 | General | |
R | 4.0 | 0.63 | 45-60 | General | |
Cossor | P1 | 3.5 | 0.73 | 20-80 | Detector and Low Frequency |
P2 | 3.5 | 0.73 | 20-80 | High Frequency | |
Cossor "Wuncell" | W1 | 1.6-1.8 | 0.3 | 30-70 | Detector and Low Frequency |
W2 | 1.6-1.8 | 0.3 | 30-70 | High Frequency | |
Dextraudion | 1.0 | 0.1 | 20-150 | General | |
Ediswan | AR | 4.0 | 0.75 | 30-80 | General |
R | 4.0 | 0.75 | 50-100 | General | |
ARDE | 1.8-2.0 | 0.3 | 20-50 | General | |
AR06 | 2.5 | 0.06 | 20-50 | General | |
PV1 | 6.0 | 1.5 | 300-600 | Low Frequency | |
PV2 | 6.0 | 1.5 | 200-400 | Low Frequency | |
PV3 | 4.0 | 0.7 | 70-110 | Low Frequency | |
PV5DE | 5.0 | 0.25 | 50-150 | Low Frequency | |
G.W.I. | A1 | 4.6 | 0.45 | 50-200 | Low Frequency |
G1 | 4.0-6.0 | 0.45 | 50-120 | High Frequency and Detector | |
Louden | (Plain) | 4.8-5.0 | 0.4 | 40-80 | Detector and Low Frequency |
(Blue) | 4.8-5.0 | 0.4 | 40-80 | High Frequency | |
Marconi Osram | DER | 1.8 | 0.4 | 30-70 | General |
DEQ | 3.0 | 0.2 | 24 | High or Low Frequency | |
DEV | 3.0 | 0.2 | 24 | High or Low Frequency | |
DE3 | 2.4-3 | 0.06 | 30-80 | General | |
DE4 | 3.6 | 0.32 | 30-150 | General and Low Frequency | |
DE5 | 5.0, | 0.25 | 30-150 | Low Frequency | |
DE6 | 1.8 | 0.4 | 30-150 | Low Frequency | |
FE1 | 4.5 | 1.5 | 24-100 | Four-electrode | |
FE2 | 4.5 | 1.5 | 24-100 | Four-electrode | |
LS1 | 6.0 | 1.5 | 300-600 | Low Frequency | |
LS2 | 6.0 | 1.5 | 300- 600 | Low Frequency | |
LS3 | 4.0 | 0.65 | 70-100 | Low Frequency | |
LS5 | 4.5 | 0.8 | 150 | Low Frequency | |
Q | 5.0 | 0.45 | 25-200 | Low Frequency | |
QX | 5.0 | 0.75 | 25-100 | Detector | |
R | 4.0 | 0.67 | 70 | General | |
R4B | 3.8 | 0.65 | 50-70 | General | |
R4C | 3.8 | 0.65 | 50-70 | General | |
R5V | 5.0 | 0.65 | 30-150 | General | |
V24 | 5.0 | 0.75 | 24-30 | High Frequency | |
Mullard | DF | 2.0-3.0 | 0.06 | 20-100 | General |
DFA0 | 3.5 | 0.35 | 30-40 | Low Frequency | |
DFA1 | 5.5 | 0.2 | 30-40 | Low Frequency | |
DFA2 | 3.5 | 0.25 | 20-25 | Low Frequency | |
LF Ora A | 1.4 | 0.2 | 20-50 | General | |
LF Ora B | 1.4 | 0.3 | 20-50 | General | |
LF Ora C | 1.4 | 0.4 | 20-50 | General | |
1-volt Ora | 1.0 | 0.25 | 30-150 | General | |
Ora A | 3.8 | 0.62 | 20-50 | General | |
Ora B | 3.8 | 0.62 | 20-50 | General | |
PA1 | 6.0 | 1.5 | 200-400 | Low Frequency | |
PA2 | 5.5 | 0.85 | 100-200 | Low Frequency | |
PA3 | 4.0 | 0.67 | 70-120 | Low Frequency | |
RA | 3.8 | 0.67 | 50-80 | Detector and Low Frequency | |
S3 | 6.0 | 0.65 | 15-30 | ||
Myers | 4.0 | 0.6 | 20-300 | General | |
DE | 2.5 | 0.25 | 20-300 | General | |
Penton | HE2 | General | |||
HE4 | 5.0 | 0.15 | 60 | General | |
Thorpe | K1 | 5.0 | 0.42 | 50-100 | General |
K4 | Four-electrode | ||||
Wecovalve | 0.8-1.1 | 0.25 | 17-45 | Detector and Low Frequency | |
Xtraudion | 4.0 | 0.4 | 30-70 | General |
The following data for the bright and dull emitters was extracted from "A First Course in Wireless" by Robert W. Hutchinson, University Tutorial Press, 1926., p. 151. This data was probably acquired by measurement of samples rather than from manufacturers published data. Data for the Marconi R4c and R5 have been corrected from other sources. Other data is from manufacturer's publications.
Data is given for bright emitter, pure tungsten filament valves and for thoriated tungsten 'dulls'. These two classes are further separated into those designed to work from one, two or three lead acid accumulator cells (~2, 4 or 6 volts). Most were designed to be operated with a series filament rheostat of about 5 or 10 ohms. This allowed for some adjustment as the cells discharged.
For comparison similar data is given for representative examples of 'azide process' and oxide coated cathode valves.
The cold resistance should be considered a rough approximation as it makes no allowance for differences in operating temperatures and powers, or for wiring and connection resistances, which may be significant at these low voltages and high currents.
I hope this information may be of some use to any collector who wishes to 'light up' one of these, by now, rather valuable artifacts.
Name | Filament Current
amps |
Filament Voltage
volts |
Filament Power
watts |
Filament Resistance(hot)
ohms |
Filament Resistance(cold)
ohms |
---|---|---|---|---|---|
Mullard Red Ring | 0.6 | 3.2 | 1.92 | 5.3 | 0.40 |
B.T.H. R | 0.63 | 4 | 2.52 | 6.3 | 0.47 |
Mullard Ora A & B | 0.65 | 3.4-3.8 | 2.47 | 5.8 | 0.43 |
Marconi-Osram R.4C. | 0.5 | 3.8 | 1.9 | 7.6 | 0.56 |
Marconi-Osram R. | 0.7 | 4 | 2.80 | 5.7 | 0.42 |
Ediswan A.R. & R. | 0.75 | 4 | 3.00 | 5.3 | 0.40 |
Name | Filament Current
amps |
Filament Voltage
volts |
Filament Power
watts |
Filament Resistance(hot)
ohms |
Filament Resistance(cold)
ohms |
---|---|---|---|---|---|
Marconi-Osram R.5 | 0.7 | 3.8 | 2.66 | 5.4 | 0.40 |
Cossor P1 & P2 | 0.75 | 4-4.5 | 3.38 | 6.0 | 0.44 |
Marconi-Osram Q.X. | 0.75 | 5 | 3.75 | 6.7 | 0.49 |
Marconi-Osram V.24 | 0.75 | 5 | 3.75 | 6.7 | 0.49 |
Marconi-Osram FE1 & FE2 | 1.5 | 4.5-5 | 7.50 | 3.3 | 0.25 |
Marconi-Osram L.S.1 & L.S.2 | 1.5 | 6 | 9.00 | 4.0 | 0.30 |
Name | Filament Current
amps |
Filament Voltage
volts |
Filament Power
watts |
Filament Resistance(hot)
ohms |
Filament Resistance(cold)
ohms |
---|---|---|---|---|---|
Met.-Vick. D.2 | 0.25 | 1.1 | 0.28 | 4.4 | 0.44 |
Ediswan A.R.D.E. | 0.3 | 1.8-2 | 0.60 | 6.7 | 0.67 |
Cossor W.1 & W.2 | 0.3 | 1.8-2 | 0.60 | 6.7 | 0.67 |
Cossor W.R.1 & 2 | 0.3 | 1.8-2 | 0.60 | 6.7 | 0.67 |
Mullard D.3 H.F. | 0.3 | 1.8-2 | 0.60 | 6.7 | 0.67 |
Mullard D.3 L.F. | 0.3 | 1.8-2 | 0.60 | 6.7 | 0.67 |
B.T.H. B.3 | 0.35 | 2 | 0.70 | 5.7 | 0.57 |
Name | Filament Current
amps |
Filament Voltage
volts |
Filament Power
watts |
Filament Resistance(hot)
ohms |
Filament Resistance(cold)
ohms |
---|---|---|---|---|---|
Ediswan A.R.06 | 0.06 | 3 | 0.18 | 50.0 | 5.00 |
Mullard D.06 H.F. | 0.06 | 3 | 0.18 | 50.0 | 5.00 |
Mullard D.06 L.F. | 0.06 | 3 | 0.18 | 50.0 | 5.00 |
Economic '06 | 0.06 | 3 | 0.18 | 50.0 | 5.00 |
B.T.H. B.5 | 0.06 | 3.8-4 | 0.24 | 66.7 | 6.67 |
Marconi-Osram D.E.3 | 0.06 | 2.4-3 | 0.18 | 50.0 | 5.00 |
Marconi-Osram D.E.Q. | 0.2 | 3 | 0.60 | 15.0 | 1.50 |
Name | Filament Current
amps |
Filament Voltage
volts |
Filament Power
watts |
Filament Resistance(hot)
ohms |
Filament Resistance(cold)
ohms |
---|---|---|---|---|---|
Mullard PM3 | 0.075 | 4 | 0.30 | 53.3 | 11.85 |
Mullard PM1A | 0.1 | 2 | 0.20 | 20.0 | 4.5 |
Mullard PM2A | 0.2 | 2 | 0.40 | 10.0 | 2.22 |
Mullard PM5X | 0.075 | 6 | 0.45 | 80.0 | 18 |
Name | Filament Current
amps |
Filament Voltage
volts |
Filament Power
watts |
Filament Resistance(hot)
ohms |
Filament Resistance(cold)
ohms |
---|---|---|---|---|---|
Cossor 210LF | 0.1 | 2 | 0.20 | 20.0 | 4.5 |
Cossor 220P | 0.2 | 2 | 0.40 | 10.0 | 2.25 |
Osram LP2 | 0.2 | 2 | 0.40 | 10.0 | 2.25 |
Osram HL2 | 0.1 | 2 | 0.20 | 20.0 | 4.5 |
Amongst suitable dull emitters for 4 volt batteries are B.T.H. B.5 (filament consumption 0.06), Marconi-Osram D.E.4 (filament consumption 0.32), Mullard D.F.A. 0 (filament consumption 0.35), etc.
The resistivity of Tungsten increases almost linearly with temperature between 300 and 3500 kelvins (°C plus 273.15). Bright emitters operate at 2500 - 2600 K, dull emitters at 1900 - 2100 K and oxide coated cathodes at 950 - 1050 K. (Note that Kelvins are units in themselves not degrees of a scale. It is incorrect to write °K.)
The cold resistance of a filament may be multiplied by about 4.5 (range 3.8 - 5.0) for an oxide cathode at its working temperature. The ratios for dulls and brights are ~10 (range: 9.4 - 10.6) and ~13.5 (range: 13 - 13.7) respectively.
Temperature Kelvins |
Relative resistance R/R300 K |
Resistivity μΩ·cm |
Cathode Types |
---|---|---|---|
300 | 1.0 | 5.65 | |
400 | 1.43 | 8.06 | |
500 | 1.87 | 10.56 | |
600 | 2.34 | 13.23 | |
700 | 2.85 | 16.09 | |
800 | 3.36 | 19.00 | |
900 | 3.88 | 21.94 | |
1000 | 4.41 | 24.93 | Oxide cathodes |
1100 | 4.95 | 27.94 | |
1200 | 5.48 | 30.98 | |
1300 | 6.03 | 34.08 | |
1400 | 6.58 | 37.19 | |
1500 | 7.14 | 40.36 | |
1600 | 7.71 | 43.55 | |
1700 | 8.28 | 46.78 | |
1800 | 8.86 | 50.05 | |
1900 | 9.44 | 53.35 | |
2000 | 10.03 | 56.67 | Dull Emitters |
2100 | 10.63 | 60.06 | |
2200 | 11.24 | 63.48 | |
2300 | 11.84 | 66.91 | |
2400 | 12.46 | 70.39 | |
2500 | 13.08 | 73.91 | Bright Emitters |
2600 | 13.72 | 77.49 | |
2700 | 14.34 | 81.04 | |
2800 | 14.99 | 84.70 | |
2900 | 15.63 | 88.33 | |
3000 | 16.29 | 92.04 | |
3100 | 16.95 | 95.76 | |
3200 | 17.62 | 99.54 | |
3300 | 18.28 | 103.3 | |
3400 | 18.97 | 107.2 | |
3500 | 19.66 | 111.1 | |
3600 | 26.35 | 115.0 |
This page last modified by AJC on Monday, 29-Mar-2010