Author Topic: May FSK signals be used to receive a signal about  (Read 18182 times)

Offline dsk

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May FSK signals be used to receive a signal about
« on: October 01, 2013, 12:09:49 PM »
May FSK signals be used to receive a signal about when the called party answers?

I don't know much about FSK, but the need of a detection of answer are still there since polarity reversal are history.
An advanced payphone controller should be able to do a lot with this information, Start the collecting, break the line when the other ends hanging up etc.

dsk

PS USA/Europe use different frequencies for FSK  ???

I have even got a regular New York number :-) 646 570 1796

Offline G-Man

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Re: May FSK signals be used to receive a signal about
« Reply #1 on: October 01, 2013, 04:29:08 PM »
The only Frequency Shift Keying (FSK) signals currently used in the U.S. PSTN are for Caller ID (CID) signaling.

Offline poplar1

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Re: May FSK signals be used to receive a signal about
« Reply #2 on: October 01, 2013, 06:13:31 PM »
FSK signaling is also used to activate/deactivate Visual Message Waiting on POTS lines.

http://tesmw.com/
"C'est pas une restauration, c'est une rénovation."--François Martin.

Offline kb3pxr

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Re: May FSK signals be used to receive a signal about
« Reply #3 on: February 20, 2018, 07:22:56 PM »
Assuming you aren't on a POTS line, I'd recommend doing this signaling outside the voice band or disabling the transmitter until this signal is received combined with disabling the FSK detector until disconnect or forward disconnect is received.

Now obviously this isn't going to be a public pay phone, but the last thing you want is to try demonstrating acoustic coupler modems and cause interference with your supervision system.

Offline HarrySmith

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Re: May FSK signals be used to receive a signal about
« Reply #4 on: February 20, 2018, 09:02:16 PM »
The topic you replied to is over 5 years old.
Harry Smith
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TCI

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do or do not"

Offline Sigmaz

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Re: May FSK signals be used to receive a signal about
« Reply #5 on: February 20, 2018, 10:33:44 PM »
Lol, better late than never..

Offline AE_Collector

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Re: May FSK signals be used to receive a signal about
« Reply #6 on: February 21, 2018, 12:21:26 AM »
But, unlike many new posts to very OLD topics, this time the OP (dsk) is still here actively on the forum.

Terry