10 replies to this topic

[Spaz101]

Well who else likes to make things.... i know i do,
well i was watching this show on techtv (spy school) and they were showing off some fancy phone secuity gear, well they showed a dtmf recorder... you know the ones, where you record the number being dialed and it shows the numbers by using the tones... well i was like wow that looks like a phun project (another fum one im messing with with my father is a gps scrambler) but i was looking everywhere for some plans... can anyone else throw me a bone if you have this file or know where i can find it

[anovak]

If you were searching for dtmf Recorder plans, than that is probably the problem: http://www.google.co...F Decoder Plans

[Captain B]

Yeah, the proper term here is DTMF decoder. And, a much quicker and easier way rather than building or buying one is to simply use a pager as DTMF decoder. If you have one, or know someone who does, just play the DTMF string into the phone, and VOILA, there's the numbers showing on the pager's display. Of course, this method wouldn't help if you were playing MF, red box tones, blue box tones, green box tones, or probaly even tones from the DTMF A, B, C and D column (Also called, the Silver Box). or basically anything other than the standard DTMF found on a standard 12 key phone keypad.

[unity]

Captian, I dont understand that last statement. Playing the tones into the telephone? Where is the pager?

[ntheory]

If you have an alpha-numeric pager you can call your pager number, play the tape, and wait for the numbers to show up on your pager. A lot of cell phone providers provide this service too.

Unfortunately you have to make sure that there are no *'s or #'s in there if your cell/pager provider uses either (or both) of those as special tones. Sometimes # is used when you're done sending your message and that can screw the whole thing up.

[unity]

Ah. All clear now. Thanks.

[Captain B]

Yeah, and when it was availible, there was a feature where you could play a DTMF string through 2600's voice BBS phone number. But, of course, that's now gone the way of the dino. But, with that hidden menu on my local ANAC (see my other post about that on this forum) it has a "keypad test" feature. Simply put, you just hit some keys on the phone keypad, and after a few moments, it'll read back what it heard. Now figure, with that, you could also send a DTMF string down the line via acoustic coupling. (A DTMF string recorded on a micro cassette, tapeless digital, or other type recorder) held up to the transmitter (mic mouthpiece) and send the tones down the line.

[ntheory]

Maybe I should pimp the DTMF decoder I wrote...

::looks around innocently::

[Captain B]

Like I always say, no time like the present. Well, actually, I don't always say that, but I am now. Heh, heh.

[ntheory]

tt-dec

Have gotten some good feedback but haven't touched it in a bit. If someone wants to give me some more suggestions I'd be willing to open this project up again.

[Spaz101]

Well I found quiet a bit on this web page
http://www.commlinx..../schematics.htm
I thout it was good at least well I knew that pager trick but my pager got disconnected (it was old too so i didnt care) but im in the process of making a DTMF decoder (thanx to all of you), and a GPS bug (ya know the tracking divice)

Spaz