1930’s GPO PBX3+9

Over the bank holiday week, I took a trip down to the Forest of Dean, with my family, to see the Thomas The Tank Engine event that was being held by Dean Forest Railway. Now, obviously, this has nothing to do with hack, tech or phreaking. However, before we left I noticed a small museum crammed into the back of the gift shop, I slowly walked around the minitures and plaquards before coming to what was easily the best part of the day - telephones, lots of telephones. Surrounding the phones was alot of old machinery, not just any old machinery, no, old school GPO telephone exchanges and manual switchboards, dating as far back as the 1930’s. Behind a glass wall was something even more impressive - a fully functional STROWGER Unit Automatic Exchange #13 (UAX13) from the 1950’s.

1950’s STROWGER UAX13

The UAX13 was protected behind a wall of 3 large glass windows, infront of which were a number of GPO 332 rotary dial phones, standard issue during the 1930, 40 and 50’s. Each phone had a 3 digit extension number which you could use to place calls between one another. And, looking closely, you could see the dial elements move as the call was placed, routed and terminated.

To the sides of the UAX13 were various manual switchboards dating from the 1930’s. Including the PBX 10+50 (10 exchange lines, 50 extensions) which was introduced in the 1930’s and continued operation well into the 1980’s.

After schooling my girlfriend in the fine art of manual pulse dialling and its implications in todays telecommunications, and, conseqeuntly, impressing a middle aged man who was simulaneously schooling his family in manual call routing, I proceeded to take a number of photo’s for the site. From left to right, top to bottom we have (click image to enlarge);

• - Collection of oldschool telephones;
• - GPO PBX 10+50 close up of panel : 10 exchange lines and 50 extensions, It was the standard private switchboard provided by the GPO from the 1930’s and was sill being fitted in the 1980’s.
• - GPO PBX 10+50 full unit
• - GPO PBX 10+50 panel
• - Stacked PBX’s from the 1930’s, bottom to top : GPO PBX 5+20, GPO PBX 2+5, GPO PBX 1+3
• - UAX13 routing section
• - UAX13 admin and control section
• - Old Payphone

If you have any problems viewing these pictures, the gallery can be found by following this link to flickr.

If you would like to view the systems yourself, you can find the museum at the Norchard station of the Dean Forest Railway, just north of Lydney. It maybe be worth contacting them first to ensure that they will be open as I am not aware of their operating times.