Australian Post Office
Telephone No. 35MW & 135MW

Telephone, Magneto, Wall

The Telephone No. 35MW was the British Ericsson Model No. N2500 and made in England. This type of magneto telephone was selected in 1912 as a cheaper replacement for the No.1 as the standard PMG telephone for installations in country areas. However the advent of World War 1 delayed its introduction until 1920, when the Ericsson Factory in Beeston, UK, had gone back to civil production. It was initially designated as the Commonwealth Ericsson but later was re-designated as the Telephone No. 35MW when the PMG numbering scheme was changed.

There were three variations in the model from 1920 to 1929. Initially the Telephone No. 35MW came fitted with an Ericsson designed transmitter with a No.3 insert with a stamped steel mount but later deliveries were fitted with a solid-back transmitter. The next variation had a simpler folded brass mount and solid-back transmitter. The last variation had a blanked off mounting hole for a dial and could be changed to CB or automatic operation by removing the magneto, changing the induction coil, adding a capacitor and strapping some links inside the case. There is no evidence that subscribers telephones were converted as it was standard PMG procedure that existing telephones were replaced with newer models when magneto exchanges were converted to CB or automatic working. However there was a Telephone No. 765AW for long line automatic working but this used a different circuit to the Telephone No. 35MW.

The British Ericsson model N2500 with solid back transmitter became the standard Australian Post Office model, Type 135MW . The APO models usually had an “Ericsson- England” transfer or a PMG brass plate. Issued in Australia from around 1920. A four-magnet generator was standard, but five-magnet ones are known ( Ericsson model N2501).

The APO also purchased the British Ericsson with a Bakelite inset transmitter, which was also called the APO Type 135MW. These had a wooden plug fitted below the transmitter to allow a dial to be fitted. Few were converted to automatic working, and most of those only retained the generator for use on party lines connected to automatic exchanges. Most dial versions of this phone were later conversions for the antique market.

With the introduction of the Telephone No. 162MT around 1932 and the later Telephone No. 232MT, the PMG ceased purchasing 35MW telephones but many thousands of them remained in service, some as late as 1965. Many of these telephones were refurbished and used for new installations when other standard telephones were not available due to shortages. These were re-designated as Telephone No. 135MW and refitted with a Bakelite transmitter housing and a No.13 insert transmitter. In 1942 some were rebuilt in the PMG Workshops and fitted with a No.164 handset. These were re-designated as the Telephone No. 235MW.

The Telephone No. 135MWH had a 2000 ohm bell coil.

Australian Post Office Telephone No. 35MW & 135MW

Australian Post Office
Telephone No. 35MW & 135MW