I'm looking for a device that will input a dialled telephone number and convert it to another number. Both input and output must be standard telephone line characteristics.
This is to change a device that has a permanent number that it dials and I need it to dial a different number.
I was guessing, from the wording of his posting, that he had some dedicated device, maybe a WebTV or one of those little dedicated email devices or maybe some industrial equipment, that was hardwired to call a specific phone number for service and that the poster wanted to divert that call somewhere else. So I was just guessing from how he described this that attacking the problem at the far end wasn't feasible.
I haven't heard of a commercial product that would do this but I did think that it might be feasible to build a little something that would reconize when the dialing device took the phone off hook and then would flip a switch, to keep the dialing device thinking it had an open line to dial, while this "device in the middle" would just poke a button on a little hand-held tone dialer device you can buy. After that was done the switch would flip back and let his original hardware continue with the call from there.
Ah. So we're talking HIGH security. Hasn't everybody know for >35 years that the 1st thing you do before burgling a building is cut the phone line and see if the cops show up?
The smart ones bring along a roach clip and just jumper it at the block. Upon leaving, they retrieve the jumper. Sometimes folks don't know they've been burgled for days.
I'm betting you could read that ROM, search and find the digit string, then replace it in an otherwise duplicate EPROM. At least, that's what I'd try.....
if it only ever dials one number you may be able do do something simpler -- record the tones you want it dial in a small solid-state audio recorder (like found in greeting cards etc) and arrange to have them play instead of its internal tone generator when it goes off-hook to dial.
Who owns the phone number that is dialed? And how did it get in there in the first place?
You might look at this DTMF transceiver or others. I have no idea if it would work for you or not. Or just DTMF receivers that could trigger something like a speed dial. I have no idea what you want to transmit.
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Or why not just buy a whole new device? Like others I would be wary of a strictly landline connection if this is important.
Now that you mention it, Bill, there are the liability issues accompanying any retrofit of this sort. Suppose a conversion device is put in place (seems to be do-able, now that Jack has provided a bit more information) and at an alarm event, it fails. Deep regret, if what's being protected is owned by Jack; lawsuit city if it's not.
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St. John
Never make anything simple and efficient when a way can be found to
When I was working with security systems all the dialers had a cut line detector. If the DC voltage went to zero, it set off the local alarm, which was a siren or two, and maybe some strobe lights. Some used a RF telemetry system with the phone line as a secondary reporting system.
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Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
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