Announcement
Collapse
No announcement yet.
How to use the old phones
Collapse
X
-
Hello La6cna
Normally one should not hear the numbering noise (in some old phone a contact insulates the earpiece)
The electromechanical systems used at the time were either a direct order step by step Strowger
or an indirect control register :
American rotary 7a (ITT in Europe)
or Swedish or agf500 Erickson or crossbar
I worked in telephone switching for 40 years
73's F1AAG
-
Originally posted by rv12p2000 View PostHello La6cna
Normally one should not hear the numbering noise (in some old phone a contact insulates the earpiece)
The electromechanical systems used at the time were either a direct order step by step Strowger
or an indirect control register :
American rotary 7a (ITT in Europe)
or Swedish or agf500 Erickson or crossbar
I worked in telephone switching for 40 years
73's F1AAG
An alternative to the Dialgizmo and the voip adapter could be an X-link adapter who lets your old phone work on your mobile, about the same way as hands-free sets in a car. The x-link understands rotary and dtmf.
Comment
-
Hello Kabel
for central battery phone there is intensity required for proper operation
In some telephones in Europe the intensity is adjusted by resistance
for German phones it was the type of micro capsule that allowed to have the required intensity in Ma
For examples the French u43 (origin Erickson) 65 ma after s63 : 35 ma
regards
F1aag
Comment
-
Originally posted by rv12p2000 View PostHello Kabel
for central battery phone there is intensity required for proper operation
In some telephones in Europe the intensity is adjusted by resistance
for German phones it was the type of micro capsule that allowed to have the required intensity in Ma
For examples the French u43 (origin Erickson) 65 ma after s63 : 35 ma
regards
F1aag
I love to learn more, so please explain more detailed.
The phones I mentioned had some kind of coil across the line with a DC resistance of a something like 300 ohms. This was to let the exchange see that the phone was off hook. The voice signal sent or received on the line worked like a local battery line just stopping the DC with a capacitor. That is the reason for needing the battery for supplying power to the transmitter (microphone)
The same system was used on the UK Type F, The US EE-8, TA43/PT, TA312/PT, Sweedish Fälttelefon MT m/37 among others
That has been working on my telephone line wen we had POTS, and it works on my ATA's and on my wireless telephone jacks.
Comment
-
Hello Kabel
for example : EE8 phone has 2 modes of operation local battery with micro batteries and generator
in central battery with the use of the hook switch and the use of the self (common battery holding coil)
In the central battery mode the intensity circulating in the line must have some value to function properly
http://www.kadiak.org/tel/ee8_1.jpg
some explanation
https://mysite.du.edu/~jcalvert/tech/phones.htm
Regards
RV12P2000
Comment
-
Thank you!
Looks like we are talking about the same thing.
Here are 2 diagrams where I have marked the DC path with red dash-dot lines.
The Tischfernsprecher 38 should have a relatively lo ohm ringer working as an holding coil.
The bunker telephone just uses the induction coil (transformer) to make the DC path.
Approx 500 ohms DC resistance is higher than what I expected, but it works here.
Comment
Users Viewing this Thread
Collapse
There is currently 1 user online. 0 members and 1 guests.
Most users ever online was 10,032 at 08:13 PM on 09-28-2024.
Comment