Old Electrical Equipment - Friedland minature doorbell transformer

Small doorbell transformer with a brown plastic cover.


Friedland doorbell transformer with brown plastic cover The transformer as it appeared when installed. The cover is made from a dark brown plastic material, and has the inevitable white emulsion paint on the lower corner.

Mains power connects at the top, and one of three lower voltages is available from the bottom terminals. In this case, 8 volts was selected.

The top terminal holes have been shoddily sealed using some R391 compound, which also has another less pleasant two word name, the first word being dog.


Back of the Friedland bell transformer Rear view of the transformer and removeable cover plate. There is no reason for the back to be removable in this way, and a modern equivalent would probably be permanently sealed in resin.

This example was screwed directly to a wall, and showed signs of overheating, as there were black soot marks extending for several inches above the transformer.