Question re item (Identified as Bellset 20)

[petervk2mlg]

Can someone tell me what the item pictured is and what function it might serve?

[duncanlowe]

Judging by the switch positions it's a mini exchange. The incoming main telephone line (exchange) can be directed to the primary (main) telephone or the secondary (extension ) phone. Also the primary phone can call the secondary as an internal call.

[Dave Moll]

What you have there is a Bellset 20.

Perhaps I should add that Duncan's description of its function is spot on.

[petervk2mlg]

Many thanks gentlemen. I'm pretty much a novice with old phones. Could I use this with magneto phones?

[Dave Moll]

It's designed for use with CB/auto rather than magneto. I'm not sure how happy it would be with magneto ringing current coming from the extension(s). The magneto included is to signal to the extension(s). What sort of magneto 'phones are you intending to use?

[petervk2mlg]

Thanks Dave. I thought that the ringing current might be a concern. I have a few magneto phones, such as the 300MT and the 338MT. These are Australian numbers perhaps but must have been based on English models.

[Dave Moll]

Looking at your circuit diagram, those 'phones should be fine as long as you resist the temptation to turn the magneto handle. Lifting the handset on the extension should make a loop which activates the indicator on the BS20, so no need for a magneto signal. Best to avoid connecting to the telephone network though - presumably, Australia has similar rules to the UK about this.

I look forward to hearing how you get on.

[Pellseinydd]

Originally Posted by Dave Moll

Looking at your circuit diagram, those 'phones should be fine as long as you resist the temptation to turn the magneto handle. Lifting the handset on the extension should make a loop which activates the indicator on the BS20, so no need for a magneto signal. Best to avoid connecting to the telephone network though - presumably, Australia has similar rules to the UK about this.

I look forward to hearing how you get on.

A magneto phone as an extension is no problem as an 'external' 'extension' phone off the Bellset 20 used a magneto to call the main on the GPO system in the UK. See GPO diagram N4309

There is a separate Australian PMG version of the 'Bell Set 20' for use on magneto systems -see picture

In the UK, the Bellset 20 was used on CB(manual) systems and on automatic exchange lines.

[Pellseinydd]

Originally Posted by Pellseinydd

A magneto phone as an extension is no problem as an 'external' 'extension' phone off the Bellset 20 used a magneto to call the main on the GPO system in the UK. See GPO diagram N4309

There is a separate Australian PMG version of the 'Bell Set 20' for use on magneto systems -see picture

In the UK, the Bellset 20 was used on CB(manual) systems and on automatic exchange lines.

Whoops picture vanished - herewith

[petervk2mlg]

Thanks. Later, I found this for sale online.

[petervk2mlg]

Pic