Automatic Telephones

n1020.jpg (8343 bytes)The caseworks of this instrument is made of moulded black Bakelite which is easy to keep clean and does not become shabby through long usage. The micro-telephones are fitted with detachable receivers and "inset" transmitters. The ringers (1000 ohms) are fitted inside and apertures are arranged to permit clear audibility of ring.

This modern, distinctive and pleasing design incorporates a form of cradle or micro-telephone rest which is not readily damaged should the instrument get violently knocked or fall to the ground.

The whole of the interior apparatus which is mounted on a frame can be removed as a unit by undoing one screw and loosening two others, the base cover being first removed by undoing one screw only.

Cords on this instrument are side entry.  The internal component fixing plate (which is cranked and has the bell located at a 45 degree angle behind the dial) is a different design to most 300 style instruments.  The case is also slightly smaller.  Click on the blueprint link, below, for more details.

Dimensions 5.5 x 9.25 x 7 inches
Weight 6 lb.

Wiring diagram No's N50647 (1935) and N53896 (1937) the difference being the resistance of the windings in the induction coil.

Introduced around 1935 and made obsolete by Ericsson in 1958

Taken from the Ericsson Telephone Catalogue, edition No. 26, Supplement 1935

Converting the N1020 to work on PST in the UK

  1. Remove the existing line cord.

  2. Move the orange wire of the dial from 8 to terminal 7.

  3. Short out the capacitor by joining the orange and orange/white wires together.

  4. Connect a 3.3K resistor between terminals 3 and 5.

  5. Connect the red wire of the new line cord to terminal 7.

  6. Connect the blue wire of the new line cord to terminal 8.

  7. Connect the white wire of the new line cord to terminal 3.

Diagram N50647 for N1020 Telephone


Click here for Blueprint of N1020

Click here for an article in the Ericsson Bulletin

Home page BT/GPO Telephones Ericsson Telephones Ericsson Home Page Ericsson PABX All Telephone Systems

Last revised: March 10, 2024