9-10-11 k/c Whistle Filter Unit

9-10-11 K/c Whistle Filter Unit.

This whistle filter is designed to be used in conjunction with the Voigt speaker unit, its object being to remove the 9 k/c whistle superimposed on your program by the neighbouring stations, chiefly after dark.

This band of frequencies is essential if the best is to be heard, and so all filters are fitted with a switch to put them out of the circuit when circumstances permit (throughout the daytime). It also acts as a very efficient "scratch filter" when a Piezo electric type of pick-up is used.

The filter is connected in the leads to the speech coil, no other alteration or adjustment being needed.

£2 10 0 ex-works. Without cover £2 2 0

In questo link sono elencati 56 modelli, di cui 51 con immagini e 2 con schemi.
Elenco delle radio e altri apparecchi della Lowther Manufacturing Co; Kent