TELEPHONE No. SA 5030
|Modified 300 type table telephone, used with Privacy
Sets No. 6 and No. 7 on Automatic and C.B. systems. The Privacy sets were speech scramblers and
afforded secure communication to a distant privacy set. Privacy sets
are also known as Frequency Changers.
These telephones were generally built up, when required, using a Telephone No. 328 Black and a Telephone No. 164 Green. The green handset was a to allow easy identification of the secure phone.
The telephone had provision for three press button keys. Normally the middle button would be left blank and only used if recall facilities or a ring button were required. The left button was originally labelled "Secret", which later changed to "Scramble" and the right button labelled "Normal".
The newly introduced Receiver Inset No. 2P was also specified for these telephones as the reception quality was considerably better than the Receiver Inset No 1L. The Receiver Inset No. 2P also used the newly introduced Earpiece No. 23 and due to war time shortages black earpieces were used when green was not available. When green handsets were not available the GPO Factory would paint the handsets a Lime Green colour.
Factory modified sets would have been marked SA 5030 but those built in the field would have retained the original Telephone No. 328 markings on the base and chassis.
Introduced in 1940.
Circuit diagram - SA 5030.
Telephone SA 5030 comprises of the following:-
These are assembled and connected as follows:-
Privacy Set No. 6A internal view
Last revised: February 21, 2023