All Dry Battery AD3

Combined H.T.-L.T. Battery.
Not listed as a Layer cell, so probably uses 60 x "B" size cells for the 90V portion. Originally referred to as "All Dry Battery No. 3"
Quoted as giving the Ever Ready "All Dry Battery Portable" 240+ hours in a 1939 advert, so LT must be 8 x "F" cells (R25) in parallel. 60 x B cells (U10) nicely fills the rest of the box and also has the "right" capacity.
10 Shillings in 1939 as it gave more than 240 hours at 1/2d per hour (12d in a Shilling, 20 Shillings per Sterling Pound, 240 pence per pound)

Balanced for 250mA LT and about 9mA HT, one of the few combo batteries without layer/"biscuit" cells for HT as it was released before layer cells used in the UK.

Connector type "H", the socket is identical to British B4 valve base (same connector and voltages on a B103, B130, B136 and B137 but the B136 & B137 balanced for half the filament current of AD3, B103 and B130)

Equivalents:

• GEC BB395
• Vidor L5054
• Others: H1178, K748, 1438, 6TA60

Here you find 204 models, 146 with images and 92 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Ever Ready Co. (GB) Ltd.; London