Radio Valve Data: 1915-1960

Keith R Thrower OBE, The Valve Museum, April, 2022.

Triode Receiver Valves (pre-1926)^*

Type or
Trademark

Filament

Anode

Grid

r_a

g_m

μ

Year

Base

Notes
and applications

^{(1)The letters indicate the three types of filaments found on these valves. B = bright emitter, D = dull emitter, O = oxide-coated.}

Volts

Amps

Volts

-Volts

kΩ

mA/V

^{(2)The year shown is when it is believed the type was first issued. This date is accurate for most types but cannot be guaranteed for them all.}

^{(3)Pin-out details for non-exhibits can be found with the base details.}

  ^{★This table lists valves that were manufactured in the UK or which were claimed to be of UK manufacture. In practice several of the smaller companies imported their valves from abroad.}

 Cleartron

C.T.08

D

3.0

0.08

30-150

18.0

0.42

7.5

1925

B4

General purpose

C.T.15

D

1.8

0.15

30-160

18.0

0.42

7.5

1925

B4

General purpose

C.T.25

D

5.0

0.25

30-150

10.0

0.90

9.0

1925

B4

Output

C.T.25B

D

5.0

0.25

90-200

20.0

1.0

20.0

1925

B4

General purpose

Post-1925 amplifying valves, frequency changers
and signal diodes

Type

Description

Filament

Anode

Auxillary Grid

Grid

r_a

g_m/g_o

R_L

P_o

R_k

Base ^{(1)Pin-out details for non-exhibits can be found with the base details.}

Year

Volts

Amps

Volts

mA

Volts

mA

-V

kΩ

mA/V

kΩ

Watts

Ω

Type

Ref

 Cleartron

 Note: for Loctal B8G read B8B, USS & USM = UX, Y8A = Footless

C-T.2.S-S-D

Gas-filled detector triode

2.0*

0.13

30-50

-

-

B4

1

1926

C-T.4.S-S-D

Gas-filled detector triode

4.0*

0.10

30-50

-

-

B4

1

1926

C-T.6.S-S-D

Gas-filled detector triode

6.0*

0.10

30-50

-

-

B4

1

1926

C-T.08

General purpose triode

3.0*

0.08

30-120

-

-

0-6

18.0

0.42

B4

1

1925

C-T.08+

AF or output triode

3.0*

0.15

60-120

-

-

5-15

8.0

0.50

B4

1

1926

C-T.10

General-purpose triode

4.0*

0.10

-

-

B4

1

1927

C-T.10+

AF or output triode

4.0*

0.10

-

-

B4

1

1927

C-T.15

General-purpose triode

2.0*

0.15

30-120

-

-

18.0

0.42

B4

1

1925

C-T.15+

AF or output triode

2.0*

0.30

60-120

-

-

4.5-21

5.0

0.70

B4

1

1927

C-T.25

General-purpose triode

5.0*

0.25

30-150

-

-

10.0

0.90

B4

1

1925

C-T.25B

RF or RCC triode

5.0*

0.25

30-200

-

-

20.0

1.00

B4

1

1925

C-T.25+

AF or output triode

5.0*

0.50

60-180

-

-

12-21

4.0

1.25

B4

1

1927

Click for pin-out: B4 - UX4 - B5 - Ct5 - UX5 - UX6 - B7 - B7G - UX7 - B8A - B8B - MO - IO - Ct8 - Footless - B9 - B9A - B9G - B10B - Others

C-T.199

Triode

2.0*

-

-

B4

1

1925

C-T.201A

Triode

5.0*

-

-

UV

1

1925

C-T 210HF

Triode

2.0*

0.10

-

-

B4

1

1929

C-T210LF

AF triode

2.0*

0.10

-

-

B4

1

1929

C-T.215

RF tetrode

2.0*

0.15

90-150

60-90

B4+st

28

1927

C-T.215H

RCC triode

2.0*

0.15

-

-

100.0

0.45

B4

1

1927

C-T 215P

Output triode

2.0*

0.15

150

-

-

B4

1

1929

C-T 215SG

RF tetrode

2.0*

0.15

90-150

60-100

B4

1

1929

C-T 410HF

Triode

4.0*

0.10

-

-

B4

1

1929

C-T 410 LF

AF Triode

4.0*

0.10

-

-

B4

1

1929

C-T 610HF

Triode

6.0*

0.10

-

-

B4

1

1929

C-T 610LF

AF triode

6.0*

0.10

-

-

B4

1

1929

Click for pin-out: B4 - UX4 - B5 - Ct5 - UX5 - UX6 - B7 - B7G - UX7 - B8A - B8B - MO - IO - Ct8 - Footless - B9 - B9A - B9G - B10B - Others