Radio Valve Data: 1915-1960

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

Imported Triode Receiver Valves^*

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.}

 Helikon

Miniwatt

D

3.0-3.5

0.06

20-80

29.00

0.21

6.0

1925Ω

B4

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

 Helikon

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

212

General-purpose triode

2.0*

0.12

-

-

B4

1

1927

216

Output triode

2.0*

0.16

-

-

B4

1

1927

406

General-purpose triode

4.0*

0.06

-

-

B4

1

1927

408

AF triode

4.0*

0.08

-

-

B4

1

1927

415

Output triode

4.0*

0.15

-

-

B4

1

1927

430

Output triode

4.0*

0.30

-

-

B4

1

1927

606

Detector triode

6.0*

0.06

-

-

B4

1

1927

625

Output triode

6.0*

0.25

-

-

B4

1

1927