Wireless Set 18, 48 or 68 static battery

[Chris Suslowicz]

The Static Battery Box for the WS18 provides HT (144 volts), Grid Bias (-12 volts) and LT (3 volts) as follows:

HT + Grid Bias = 156 volts with a tap at 12V, from 2 x 60 volt batteries (120V) + 24 volts from two of the "8-cell refill" batteries, totalling 144 volts, and a third "8-cell refill" battery to provide Grid Bias.

The filament (LT) supply was provided by two "O" cells (which may have been either a single large cell or a cardboard case with several cells connected in parallel).

The static battery was considerably higher capacity than the 'battle battery' and the HT section would have lower resistance so that the 6-volt difference would not be a problem.

There was a US manufactured equivalent for the WS48 that is almost identical except that the cells/batteries listed for filling it are American types.

Your second "static battery box" is actually the HT battery for Wireless Set No.1, and is filled with 20 of the "8-cell refill" batteries to provide 240 volts HT.

The "8-cell refill" consists of 8 approximately AA-sized cells in series, with a negative lead and two brass terminals for +6 and +12 volts. They were used in various remote control units to provide relay power, and were still in production in the 1970s or later.

Chris.