How we Restore 300 Series Telephones (1937-1959)

Before we start work on 300 Series Bakelite telephones in our workshop we inspect them thoroughly checking all the electrical and mechanical components, to make sure no key parts are missing or damaged.


Professionally repair the electrical and/or mechanical faults.

Perform a very comprehensive electrical and mechanical service of the 300 series telephone.

Then we will adjust and lubricate (using the correct oils) all the mechanical elements of the telephone such as the bell mechanism, the rotary dial and switch hook assembly etc. This will ensure the peak performance of your 300 Series Bakelite rotary Telephone.

Please note that the cost of any missing or faulty part would be additional to these repair costs. However we would include these costs in the detailed quote after examination in our workshop.

Finally we always "soak test" the telephone on a comprehensive (ex BT Telephone Exchange) telephone tester for several days before returning the telephone.


Convert the 300 Series Telephone so that the phones ringing circuit has as REN of 1 and fit a rectifier to prevent acoustic shock. Because we convert and test them professionally we make sure the telephone's electrical circuits will not cause problems with your other telephones or impact your Broadband speeds/stability.

Our 300 Series Bakelite Phone Conversion also includes the cost of the following items:

  • A new high quality (round profile) 3 meter plastic black line cord that plugs into a standard BT style socket. We have these line cords made in the UK and they use the correct GPO telephone colour code wiring.
  • We always replace the old carbon granule microphone with a new crackle free electronic microphone as standard.

We then perform a comprehensive electrical & mechanical service of the 300 series telephone.

We adjust all the mechanical elements such as the telephone bells, rotary dial (speed and ratio) and switch hooks etc. This will ensure the peak performance of your 300 Series Bakelite Telephone.

Full Restoration

Restoration includes all the items listed in option 2. In addition we also perform a deep clean and a 4 stage restoration of all the individual Bakelite parts. This involves both hand renovation and the use of a buffing machine (using several unique Bakelite restoration compounds). We do NOT use coloured polishes or dyes to simulate a restored Bakelite finish. We also clean the dial mechanism and internal components (such as internal bells) to the same high standard.

This 4 stage Bakelite telephone restoration process requires a lot of "time" using unique cleaning/polishing compounds and complex restoration techniques. As you can imagine the majority of the cost is in the time it takes to perform these tasks.

As with all our other options we always test the 300 series telephones thoroughly on a comprehensive BT/GPO telephone tester before it leaves our workshop.

After completing a full restoration we "soak test" the Bakelite 300 series telephones for 5 to 7 days .

Please note that Bakelite is a thermosetting plastic so it is not possible to repair any splits or cracks.

The 300 series Bakelite telephones (1937-1959) were the first British Telephones to contain an internal bell. When serviced and adjusted correctly these mechanical bells sound fantastic.

Please read our FAQ (Frequently asked Questions) for more details on old telephone compatibility regarding rotary dial phones etc.

312 Bakelite Telephone

Our 300 Series Guarentee

After all the work has been completed all our Bakelite telephones are soak tested in our telephone workshop our chief engineer will quality check your 300 series telephone thoroughly. We pride ourselves that you will not find better attention to detail or quality workmanship anywhere else.

All our work and any replacement parts (vintage or new) we provide are guaranteed for twelve months.

Antique Telephone Engineer