Radio Valve Data: 1915-1960

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

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

 BSA Standard

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

G125

General purpose triode

1.0*

0.25

30-60

-

-

25.0

0.22

B4

1

1926

G125A

General purpose triode

1.0*

0.25

30-60

-

-

25.0

0.22

UV

1

1926

G225

General purpose triode

2.0*

0.28

60-120

-

-

17.0

0.50

B4

1

1926

H125

RF or detector triode

1.0*

0.25

60-90

-

-

45.0

0.26

B4

1

1926

H125A

RF or detector triode

1.0*

0.25

-

-

45.0

0.26

UV

1

1926

P125

Output triode

1.0*

0.25

-

-

B4

1

1926

P125A

Output triode

1.0*

0.26

-

-

B4

1

1926

P425

Output triode

4.0*

0.28

130

-

-

2-8

1.10

B4

1

1926

P425A

Output triode

4.0*

0.29

130

-

-

2-8

1.10

B4

1

1926

P485

Output triode

4.0*

0.90

130

-

-

3-12

1.00

B4

1

1926

P612

Output triode

6.0*

0.12

130

-

-

2-8

1.00

B4

1

1926

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

 BSA Standard

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

G.125

General-purpose triode

1.0

0.25

60

-

-

25.0

0.24

B4

1

1925

G.125A

General-purpose triode

1.0

0.25

50

-

-

25.0

0.24

UV

1

1925

H.125

RF or detector triode

1.0

0.25

60-90

-

-

45.0

0.24

B4

1

1925

H.125A

RF or detector triode

1.0

0.25

60-90

-

-

45.0

0.24

UV

1

1925

P.425

Output triode

4.0

0.90

120-160

-

-

2-8

5.5

1.00

B4

1

1925

P.425A

Output triode

4.0

0.25

120-160

-

-

2-8

6.0

1.00

UV

1

1925

P.A.4

Output triode

4.0

0.25

100-160

-

-

5-15

6.0

1.00

B4

1

1925

P.B.1

Triode (no data)

-

-

-

-