High-efficiency multiple magneto boards

The author points out that magneto boards have several advantages in isolated or sparsely populated districts. Its main asset is its simplicity, low cost and easy and inexpensive maintenance. The transmission is of high quality and independent of the length of the subscriber's line so far as talking battery is concerned. Lines of higher resistance (iron wire) can be used. The wider operating limits obtained by locating the talking battery and the signalling generator on the subscriber's premises makes for successful operation with a low-grade line plant. Also, where drop indicators are used instead of lamps and relays, no power plant is required. The paper describes two improved types of magneto boards recently introduced, in which various operating improvements are incorporated. The article is illustrated with photographs and circuit diagrams.