How to identify and date a pyramid telephone?
 

I got myself my first UK non field telephone.
The only one I have seen here in Norway, but I'm sure that others exists too.

One before, and ne after picture.

I had at least some cloth covered cords and the transmitter capsule was not good, so I soldered a pen spring in bottom of a modern capsule, and it worrks like a charm.

All you can tell me about this phone are welcome, Thank you!

dsk

PS! am also posting here: http://www.classicrotaryphones.com/f...6018#msg236018 DS

Re: How to identify and date a pyramid telephone?
 

Is there anything on the base that may provide any identification? This is where model numbers and date codes are usually printed.

Re: How to identify and date a pyramid telephone?
 

If that circuit diagram (photo 2) applies to this telephone then its what it says on the diagram, a Telephone 232.

Diagram N332 is the circuit for the telephone, N526 is the circuit for the associted 'Bell Set' (bell + capacitor) that the telephone line cord connects to. And N4300 is the diagram for the entire installation.

You can get these diagrams from Sam Hallas's web site. A google search for that name, or for 'N diagram' will find them.

Re: How to identify and date a pyramid telephone?
 

The only stamp on the under side is No1/232 F. G.P.O. TE2

TE and 2 is also stamped in the bakelite.

Re: How to identify and date a pyramid telephone?
 

The 'F' after the 232 suggests the dial has figures only, rather than letters and figures. What is stamped (moulded) in the handset? There's sometimes a date of manufacture on there but not always. And it mightn't be the original handset, of course.

Re: How to identify and date a pyramid telephone?
 

The handset has this:
TE37
GPO-No 164
234

So I guess on 1937.

Re: How to identify and date a pyramid telephone?
 

A date of 1937 for the handset makes sense. The TE designation on the handset and the phone itself is the GPO abbreviation for the manufacturer Telephone Manufacturing Company. Remember that these phones were rented to users and were regularly repaired on site or refurbished back at the factory so that the dates on the component parts don't always correspond to the original manufacturing date.

The forum mentioned in your first post is US based and the enthusiastic members there may not have much knowledge of phones originating from the UK just as I know nothing at all about US phones.

Alan

Re: How to identify and date a pyramid telephone?
 

Lovely, and a real bargain.

You can polish the Bakelite with what the GPO would have originally used, i.e. Greygate Polishing Paste No.5 :https://www.ebay.co.uk/i/12380745463...xoCNzoQAvD_BwE

Re: How to identify and date a pyramid telephone?
 

Thank you! Regarding the other forum: You are right here too, but the forum has a structure where it is possible to sort and easily find what you are looking for. Sitting her in Norway, and I have actually never touched a pyramid phone before. It was no big issue to understand the phone thanks to Sam Hallas's web site, but still i got 2 things, 1) dating the phone if possible, and 2) getting the anti sidetone circuit working.

Here in this forum I got help to at least indicate the age of the phone.

Regarding 2) I have to be careful to state that it is wrong info on Sam Hallas's web site, but by opinion it is. Ill take that in next reply. I have to make some drawings to show what I think. It may just be my bad English, and not the Sam Hallas's web site who makes the confusion ;)

Re: How to identify and date a pyramid telephone?
 

Actually Sam Halls web page is right! but only if you use the UK master socket with a common capacitor. Even when I know that system it was confusing!

The chemais under will ekplain whats happening:

Re: How to identify and date a pyramid telephone?
 

For my use with no ringer, and just 2 wires, I need the capacitor. Since that capasitor should hve as small resistance as possible for the speech but should block DC the original 2 uF was the best regarding size, cost and function.
That is why I say 2 uF or more.