See also Telephone 345
FOR USE ON MAGNETO CALL AND CLEAR SYSTEMS GIVING THE HIGHEST GRADE SERVICE UP TO THE MOST EXTREME CONDITIONS
Telephones AB. 590 and AB. 590G are for use on very heavy bridging circuits.
Telephones AB. 530, AB. 535 and AB. 590 are supplied with push button to cut out the ringer coils and short circuit the induction coil, so as to cut out the home bell when ringing out, and also to give increased reception efficiency during conversation.
Was Telephone 345 except it is fitted with a 1000 ohm ringer.
Known as the APO Telephone No. 1.
In both the 1905 and 1912 Ericsson Telephone Catalogue
Last revised: July 24, 2021