Buying: Check for Missing Insides
WARNING, with reference to rare 232 British Bakelite telephones there has been a recent trend in a very worrying practice.
Please read carefully, this sounds like a small problem however it is NOT. Fixing this can be VERY Expensive.
This only appears to be happening to 232 telephones as shown above and NOT to Bakelite telephones that are mounted on-top of their Bakelite Bell-sets (Combined Sets) as pictured below:
It appears that some people carrying out telephone restoration and conversion on these iconic pieces of history are systematically removing vital original wiring and components from the inside of these telephones. This is worrying for two very good reasons:
1) It degrades the speech quality of these telephones by approximately 75%. They still appear to work however the sound quality, usability, and compatibility with the British telephone system is significantly reduced.
2) The intrinsic historic value and originality of these telephones is significantly degraded.
If you wish to check if your Bakelite telephone has suffered this fate you will need to look inside your telephone.
Step 1: Loosen the base by unscrewing the two screws in the middle (not the 4 feet)
Step 2: Gently lift off the body off the base.
You should see something very similar to the photograph below.
However if you see that the large round component (the ASTIC coil) is missing as in the photograph below you may have a big problem.
If your telephone insides look like the photograph above someone has cut out a key component of your Bakelite Telephones speech circuit. This component is called an ASTIC coil (or Induction Coil No 24). See ASTIC coil picture below:
I believe that this removal of wiring and ASTIC coil is being performed out of ignorance rather than malice. Possibly in the mistaken belief that this is not key to speech on a modern telephone line.
I can assure whoever is doing this that the ASTIC coil and its wiring is still as key today as it was when these telephones were originally designed.
Some people theorise that the ASTIC coil is being removed to make space for a modern small bell (AKA Chinese bell). See below:
However although most purists resist fitting these Chinese Bells the can be successfully fitted without cutting out the ASTIC coil.
I worked for BT for over 32 years and have over 50 City and Guilds qualifications in Advanced Telecommunication & Electronics (up to Degree standard). Although we live in a digital age land-line telephones are still based on Analogue circuitry that has not fundamentally changed since the 1920's.
If you are one of the telephone restorers performing this practice please contact me and I will be happy to explain the technical detail of why this practice is a very BAD idea.
For the general public I would urge you to check with the people who supply your telephone that they are not doing this to the telephones they are selling you.