Re:Rotary Cellphone
by dublin on Wednesday February 12, 2020 @02:19PM
(#22311808)
The old GTE payphones up in Georgetown, Tx (suburb of Austin, now) when I was a kid would let you dial with the switchhook - no coins required. Agreed, zeroes were a pain, but this was partially compensated for by the fact that 5-digit dialing worked for any local number, e.g. 3-1234 got you 863-1234. Interestingly, most VoIP adapters support the pulse dialing of an old phone, but very few have the cojones to actually ring one that has a physical bell rather than an electronic ringer...
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Er, I'm not sure where you got this information from, but I can tell you categorically that ATAs that support pulse dialing are few and far between. Source: I have a vintage phone collection and wish bitterly the reality were different. (I use a Avaya PBX as a bridge to asterisk/IP telephony as a practical alternative)
That’s because the traditional physical bell needs a high voltage (relative to the digital circuits in modern hardware).
https://www.epanorama.net/circuits/telephone_ringer.html:
”The voltage at the subscribers end depends upon loop length and number of ringers attached to the line; it could be between 40 and 150 Volts.”
I think they also (relatively to the hardware in a VoIP adapter) need a large amount of power.
So, to ring that bell, you need to transform your 5V/3V/…, and you need a larger power circuit. That isn’t worth it for the few who still have an old-style telephone.
I think you need the high voltage anyway, even for a fake bell. The power is probably the problem.
Re:Rotary Cellphone
by defnotarobot on Wednesday February 12, 2020 @07:52PM
(#22314388)
I've seen some grandstreams that'll run a ringer.
Re:Rotary Cellphone
by therealidiot on Thursday February 13, 2020 @01:50AM
(#22315839)
Second this, I've had no trouble ringing an old GPO 746 telephone (and very loudly) with a Grandstream HT802