|
Vintage Telephony and Telecomms Vintage Telephones, Telephony and Telecomms Equipment |
|
Thread Tools |
19th May 2020, 3:32 pm | #1 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Converting a 1950s Ericsson phone for "normal" working
Hello everyone,
I recently got hold of a ~1950 Ericsson N1071A16 wall phone, which is also marked as type H1385, a New Zealand post office designation. The numbers on the dial are backwards compared with what we're used to, but otherwise it's very similar to the UK variants, which have an almost standard 300-series chassis albeit modified to work in a wall-mounted case, see here: https://www.britishtelephones.com/ericsson/n1071.htm The dial was a mess (seized clutch and broken return spring) but I've restored everything now and would like to use it at home. However, there's a catch... this seems to be an instrument re-designed for the NZ telephone system. It has an extra changeover contact on the gravity switch and a separate earth connection. There's also an odd, asymmetrical leaf spring on the bell motor. I've attached a photo of the paster in mine. You can see it's very similar indeed to the standard GPO 332: https://www.britishtelephones.com/gp...t322paster.jpg So, to the big question... What do I need to do? Certainly, linking T2-T3 would be a start, connecting the line to the points marked A and B. Two-wire working would be fine. And obviously, I realise that I'd need to do a bit of mental conversion when dialling! Thanks, experts, Nick. EDIT: Mods, please delete the "party line" bit from the title Last edited by Nickthedentist; 19th May 2020 at 3:43 pm. |
19th May 2020, 4:38 pm | #2 | |
Dekatron
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,127
|
Re: Converting a 1950s Ericsson phone for "normal" working
Quote:
To save the mental gymnastics, could you swap the dial, or at least the number ring, for a UK one? And no, I don't claim to be an expert!
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley) |
|
19th May 2020, 8:56 pm | #3 | |
Heptode
Join Date: Jul 2007
Location: Flintshire, UK.
Posts: 707
|
Re: Converting a 1950s Ericsson phone for "normal" working
Quote:
Quite easy to mod to have an identical circuit to a GPO Tele 332 - a) Remove the green wire that runs between T1 and Switchhook spring No 3 b) Move the brown wire from T3 to T1 c) Remove the Slate(grey) wire between Dial terminal Strip 2 and Switchhook No 4 d) Remove the Orange wire between T12 and Switchhook 7 e) Strap Dial Terminal strip 2 and 3 f) Strap T11 and 12. Then your telephone is identical circuit to a Tele 332 except that Switchhook make contacts are No 5 and 6 rather than No 3 & 4 on the Tele 332. Line A wire goes to T1 and B wire to T9 as per Tele 332 Then just go ahead with converting a Tele 332 to three wire as per Bob F's instructions - Then the telephone is ready to go. Note the NZ dials are identical to the UK ones except for the fingerplate. |
|
19th May 2020, 9:38 pm | #4 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Re: Converting a 1950s Ericsson phone for "normal" working
Thanks Dave for your thoughts, and Ian for your in-depth advice... I tried to work it out for myself, but it made my head hurt. That's amazing, I will have a go later this week.
I willl look up multi-party party lines and code-ringing. Yes, I thought the dials were identical and have swapped the fingerplate in anticipation, but nice to have it confirmed by someone who knows! Nick. Last edited by Nickthedentist; 19th May 2020 at 9:44 pm. |
19th May 2020, 9:44 pm | #5 | |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Re: Converting a 1950s Ericsson phone for "normal" working
Not much to be found except stuff like this:
Quote:
Thanks again, Nick. |
|
20th May 2020, 1:26 am | #6 | ||
Dekatron
Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,713
|
Re: Converting a 1950s Ericsson phone for "normal" working
Quote:
http://www.awaruamuseum.co.nz/nzpo-e...telephone.html Party Lines Initially it was common for more than one customer (subscriber or 'sub') to share a telephone line, particularly in rural areas where for example, one phone line might provide service to all the farms in a valley. There was no privacy on such a line, as all users could hear every ring on the line and by lifting their handset could listen to any other phone call. A system of coded short and long rings was used to identify who a call was for. The shorter Morse Code letters were allocated first, however on 10 party lines the ring codes inevitably were longer. The ring codes used were A, D, M, R and S for a 5-party line. These were extended by using J, K, U, W and X for a 10 party line. Example ring codes for S, M and W were: S was three short rings; M was two long rings; and W was a short followed by two long rings. Consideration for others was important. For instance, when first picking up the phone a user would say 'Working?' to see if the line was in use. They would limit the length of their call - say to 5 minutes on a line with many subscribers, then at the end of their call would crank their phone 'magneto' - the ring generator - to make a short ring burst on the line advising the operator and all other users that they were finished and the line was available.
__________________
-- Graham. G3ZVT |
||
20th May 2020, 5:33 am | #7 | ||
Dekatron
Join Date: May 2006
Location: Invercargill, New Zealand
Posts: 3,457
|
Re: Converting a 1950s Ericsson phone for "normal" working
Quote:
It was only in remote areas - for example my wife grew up in Monowai and they had a party line until the late 80s, on an automatic exchange by that stage and it would have been one of the last areas. The last couple of manual exchanges were gone by then too - funnily enough Queenstown was one of the last. As far as I'm aware our phone system shouldn't be significantly different to the UKs - BT jacks are still in common use here, and one of the reasons for our emergency number being 111 is because of sharing equipment designed for UK's 999 system. If you google "NZPO type 100" you'll find a very familiar looking device as well.... It might just be me, but I always thought counting from 0-9 made more sense than 0-9...1 |
||
20th May 2020, 12:43 pm | #8 |
Heptode
Join Date: Jan 2008
Location: Hakadal, Norway
Posts: 643
|
Re: Converting a 1950s Ericsson phone for "normal" working
The dialgizmo may be switched to read reverce pulses, and convert them to DTMF. I have several Oslo telephones and have tested that
dsk |
20th May 2020, 1:03 pm | #9 | |||
Heptode
Join Date: Jul 2007
Location: Flintshire, UK.
Posts: 707
|
Re: Converting a 1950s Ericsson phone for "normal" working
Quote:
The other type of party line was a 5 party 'revertive call' line where the caller would dial the code of the required 'party phone' then replace the handset. It used loop dialling rather than the earth 'Simplex' dialling. All the phones would then ring with the relevant code ring. When the person whose code it was answered, the ringing would stop and the caller would lift the phone and they could speak. WE have managed to get the 'multi-party' party line with the S/A/D/M or R code ringing working on CNet with up to five telephones working on an ATA - only works with Linksys ATAs. Luckily I've got hundreds of NZPO circuit diagrams for their Strowger exchanges including the NZ version of the GPO's UAX13. |
|||
20th May 2020, 2:38 pm | #10 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Re: Converting a 1950s Ericsson phone for "normal" working
Fantastic, all very interesting stuff, thank you!
Does anyone know what the little spring on the bell motor (post 1, last pic) is for, please? Nick |
20th May 2020, 2:56 pm | #11 |
Dekatron
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,127
|
Re: Converting a 1950s Ericsson phone for "normal" working
Could it be to ensure that it always returns to the same rest position regardless of where in the ringing cycle it was stopped? I'll leave others to say why this may be desirable!
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley) |
20th May 2020, 2:58 pm | #12 |
Heptode
Join Date: Jul 2007
Location: Flintshire, UK.
Posts: 707
|
Re: Converting a 1950s Ericsson phone for "normal" working
|
20th May 2020, 3:03 pm | #13 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Re: Converting a 1950s Ericsson phone for "normal" working
Thank you both, the latter had crossed my mind.
|
20th May 2020, 3:14 pm | #14 |
Dekatron
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,127
|
Re: Converting a 1950s Ericsson phone for "normal" working
I was wondering about anti-tinkle, but was thinking the effectivenes would depend upon the polarity of the voltage change causing the tinkle. I suppose, however, if the spring holds the clapper in contact with one gong it couldn't ting against that one, and the resistance of the spring prevents it reaching the other one.
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley) |
20th May 2020, 4:20 pm | #15 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Re: Converting a 1950s Ericsson phone for "normal" working
I suppose I could experiment...
I'm still intrigued how a 1950s wall-mounted instrument from NZ ended up over here, being sold by a house clearance outlet on eBay. N. |
20th May 2020, 8:57 pm | #16 |
Dekatron
Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,713
|
Re: Converting a 1950s Ericsson phone for "normal" working
My Bell No 1A has a similar bias spring
__________________
-- Graham. G3ZVT |
20th May 2020, 9:09 pm | #17 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
|
Re: Converting a 1950s Ericsson phone for "normal" working
Well I never, that's interesting.
|
20th May 2020, 11:20 pm | #18 | |
Heptode
Join Date: Jul 2007
Location: Flintshire, UK.
Posts: 707
|
Re: Converting a 1950s Ericsson phone for "normal" working
Quote:
And there are some NZ Party-line phones still working on a mile long code ringing party line in the UK - on a little island with no mains electricity or flushing toilets! Time has stood still there - the last house there was built 150 years ago! Only three houses are lived in all the year round. Took a long while to install as cabling had to be virtually 'invisible'. Even filmed for a TV program whilst I was installing one of the phones and interviewed for Radio 4 on another trip! Last edited by Pellseinydd; 20th May 2020 at 11:35 pm. |
|
21st May 2020, 5:36 pm | #19 |
Tetrode
Join Date: Nov 2017
Location: Bromsgrove, Worcestershire, UK.
Posts: 63
|
Re: Converting a 1950s Ericsson phone for "normal" working
|
21st May 2020, 6:50 pm | #20 |
Dekatron
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,127
|
Re: Converting a 1950s Ericsson phone for "normal" working
That does appear to be the prevailing opinion in this thread.
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley) |