Ever Ready and Lissen

Lissen bought in valves without bases and added their own. It’s not clear if ANY early Lissen valve wasn’t bought in. In 1928 Ever Ready bought control. By 1935 Noah Cole the founder of Lissen was gone as he had founded Vidor in 1934.

Ever Ready adopted a continental style scheme and from 1935 bought Mullard valves (or possibly some were really made by Philips in Netherlands) but used their own continental style scheme

A = 4V (usually indirect, but not always)

C = 200mA series indirect, any voltage.

K = 2V (usually direct battery filament)

S= 4V (Usually direct)

Next digit is number of electrodes. i.e. 2 = Diode,  8 = Octode, though Pentodes are 7. If it’s a single device, then second digit is zero. If a dual device such as TDD13C, then 2nd digit is different device C23B, the “3” indicates a Triode. Thus K33A is a dual 2V Triode and  K77B  is a Dual 2V direct pentode.

The suffix letter indicates a later version, or for battery types selected matching bias; for Push Pull, or Screen grid bias tap to use.

All the All Dry valves (1.4V) using Ever Ready Branding used Mullard type numbers. Mullard used US numbers 1938 to 1946 for US imports they resold.  In 1945 the late 1930s 5 pin and 7 pin 2 volt valves (Ever Ready K series)  had Octal bases fitted as there was a market still for Accumulator fed LT (no home Electricity and cheaper than All Dry LT batteries if a nearby cycle shop or neighbour to charge the cell). The 2 Volt valves thus in radios sold up to 1950. But Ever Ready being a Battery maker sold no sets using 2V LT after 1939. Only one post 1942 Ever Ready set even had a mains option, the 1956 BEREC Fiesta.

From Mullard Valve Guides

Usually AC parallel 4V (Mostly Indirect)

A11B IW4-350
A11C IW4-500
A11D IW4-350
A20B 2D4A
A23A TDD4
A23B TDD4
A27D Pen4DD
A30B 904V
A36A TH4
A36B TH4B
A36C TH4B
A40M MM4V
A50A SP4
A50B SP4B
A50M VP4
A50N VP4A
A50P VP4B
A70B Pen4VA
A70C PenA4
A70D PenA4
A70E PenB4
A80A FC4

All AC/DC series 200mA (All indirect)

C10B UR1C
C20C 2D13C
C23B TDD13C
C27D Pen40DD
C30B HL13C
C36A TH21C
C36B TH30C
C36C TH22C
C36N TH30C
C50B SP13C
C50N VP13C
C70D Pen36C
C70E Pen36C
C80B FC13C

All DC battery parallel Direct 2V (Lead Acid Cell)

K23A TDD2A
K23B TDD2A
K30A PM2HL
K30B PM1LF
K30C PM2HL
K30D PM2HL
K30E PM2DX
K30G PM2A
K30K PM2HL
K33A PM2B
K33B PM2BA
K40B PM12
K40N PM12M
K50M VP2
K50N PM12M
K70B PM22A
K70D PM22D
K77A QP22A
K77B QP22B
K80A FC2
K80B FC2A

Usually Mains 4V Direct

S11A DW2
S11D DW4-350
S30C AC044
S30D AC042