Phone Modification

[Keith.p]

I have a Gecophone that I would like to use, it works but its a PAX phone.
So any information on wiring diagrams or any parts needed would be very helpful.
Thanks.

[wds]

Nice phone.  I'm watching one on Ebay right now that I wouldn't mind adding to my collection. 

[dsk]

I like to try to understand those diagrams, are you able to get a better picture of the diagram?

dsk

[Keith.p]

This may help.

[dsk]

This telephone is made for just having transmitter and receiver in series, so I guess this will be OK.
If the dial has the right speed and pulse ratio, (and why should it not) you should be able to use it just connecting the telephone line to the terminals L1 and L2. It will not ring!

If you are going to use it for many long conversations, (more than expected from the designer) I would consider to change the wiring. If you want a ringer, you have to put in another ringer and capacitor, or use an external ringer. (another option is to use a capacitor, a relay and a battery, just to use the built in ringer, experimenting with the use of a capacitor and a 110 to 5 - 20V (approx) transformer)

dsk

[Bill]

It looks like there is DC continuity between L1 and L2 either on-hook or off-hook - not a good thing for a direct hookup.

What are the two devices at the lower left of the diagram, one labeled 30 ohms and one labeled 100 ohms? Presumably, one of them (which?) is the ringer, though both values seem very low for ringer resistance.

Bill

[dsk]

It looks like there is DC continuity between L1 and L2 - not a good thing for a direct hookup.

What are the two devices at the lower left of the diagram, one labeled 30 ohms and one labeled 100 ohms? Presumably, one of them (which?) is the ringer, though both values seem very low for ringer resistance.

Bill

Yes, it is a DC continuity when off hook, and you get DC in your receiver, but that is the original design, so I guess it may work just as original.

The ringer (30 Ω) in parallel with a resistor (100 Ω) are quite typical for a battery call, and definitely not made for regular telephone lines.

I have been proud of being able to substitute parts and getting things to work, today I prefer, if possible to make adapters to get odd stuff like this one stay in original shape and adding an external adapter.  

In this case, if the phone was mine I would connect the line to L1 and L2 and try to get the voice circuit in working order. When that's OK I would try to get ringer to ring, that's requires an adapter circuit.

dsk

Edit:
Here comes a suggestion to an adapter:
The relay has to operate well at ringing current in series with a 0.5-1µF 200V capacitor.
The battery cold be a 9V small battery, ore some AA(A) cells in series, take what you have and test.
An alkaline battery will last for years.

[Keith.p]

Sorry computer blow up, slow laptop time.
Not worried about keeping the originality of the phone, but I would like it to be a complete working phone, it works with L1 & L2 connected, I have gone and fitted a three wire hand set lead, also a modern bell, so far.
It was only a £20 phone.

[HowardPgh]

I think that could be wired like a 202 phone with one of those AE mini networks.
Of course you woul have to change the ringer and get a three conductor handset cord.
Very nice looking phone as is.

[dsk]

Sorry computer blow up, slow laptop time.
Not worried about keeping the originality of the phone, but I would like it to be a complete working phone, it works with L1 & L2 connected, I have gone and fitted a three wire hand set lead, also a modern bell, so far.
It was only a £20 phone.

£ means location UK?

This is  a great opportunity to take a look at non US telephone hybrid's.

Do you have any telephones to cannibalize? The best would be one using a 3 wire handset cord. Then you could put in an ATCS circuit. It may be better, and some experience of modernizing the circuit.

No need for rushing this, it works as it is  

dsk

[twocvbloke]

I think that could be wired like a 202 phone with one of those AE mini networks.

If it's to be kept as original as possible, fitting it with GPO 162/232 Pyramid phone (which GEC was one of the manufacturers of) parts would be better (rather than using US phone parts in what is typically a british phone), as they're designed to fit that case anyway, and no-one will notice any difference...

The ringer could be left in place, but disconnected from the circuit and a GPO Bellset No. 26 (includes the ringer capacitor)...

[Keith.p]

That would be a option, I have a scrap pyramid phone that I got cheap.
3 wire handset cord has already been replaced, as I don't know anything about phones, or if I needed a capacitor or not.
Sorry £ UK.

[dsk]

Great, I guess you have everything needed.

You make good photos, so this should be possible.

dsk