Zadel
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Hardware puzzle: Recording modem sounds
I'll start off by stating that this may be in the wrong forum -- it seems that it belongs somewhere between here and the puzzle area.... Thus it has been posted in both. For simplicity purposes, I would prefer it if you post your suggestions at https://www.experts-exchange.com/questions/20795133/Hardware-puzzel-Recording-modem-sounds.html. If however, you post here, that is fine.
Anyway, when files are sent across phone lines via a modem, they are first converted into sounds by the modem. I would like to capture the sounds onto an audio tape. In essence what I am wishing to do is connect a tape recorder to my modem and have the modem send the file to the tape recorder. I would also like to be able to do the reverse process.
So far, I have spliced telephone cable with an RJ-11 to a cable with an audio in connector. The problem I am now running into is getting the modem to send a file with no dial tone or handshaking occurring. I've looked at some of the AT commands that can be used in hyperterminal, but so far I have not had any luck.
Anyone ever played with this before?
Thanks.
Anyway, when files are sent across phone lines via a modem, they are first converted into sounds by the modem. I would like to capture the sounds onto an audio tape. In essence what I am wishing to do is connect a tape recorder to my modem and have the modem send the file to the tape recorder. I would also like to be able to do the reverse process.
So far, I have spliced telephone cable with an RJ-11 to a cable with an audio in connector. The problem I am now running into is getting the modem to send a file with no dial tone or handshaking occurring. I've looked at some of the AT commands that can be used in hyperterminal, but so far I have not had any luck.
Anyone ever played with this before?
Thanks.
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>>>Huh?
I stand by my comments! It's NOT possible to do this regardless of the recording device.
It would probably help if you read the ENTIRE question as well as my explaination.
Doh!
I stand by my comments! It's NOT possible to do this regardless of the recording device.
It would probably help if you read the ENTIRE question as well as my explaination.
Doh!
well, i support jhance..
but this question reminds me of the older commodores and other such computers where you could use tapes as your storage media.
but those times had a different cassate socket to connect the tape recorder thrugh line-in.
data transfer rates as well as capacity was not so great. even the original ibm pcs had the same thing.
most of the pcs had basic code embedded in the bios which kicked off if the pcs is not booted with any bootable disk...you can still see the placeholder by calling int 18 on any modern pc thru dos-debug
now coming back to your problem, as jhance said, u cannot do exactly what u want.
but if u still wish to store data on tape, i have one idea....
you can connect the tape recorder thrusound card's line-in socket and then write a program to output the dataformat thru it which will be recorded.
and another piece of code will then recover back the data from the tape when connected in reverse way...
you may need to do some hard thinking and experimenting on this...but i think this can be done...
waiting for others to comment...
but this question reminds me of the older commodores and other such computers where you could use tapes as your storage media.
but those times had a different cassate socket to connect the tape recorder thrugh line-in.
data transfer rates as well as capacity was not so great. even the original ibm pcs had the same thing.
most of the pcs had basic code embedded in the bios which kicked off if the pcs is not booted with any bootable disk...you can still see the placeholder by calling int 18 on any modern pc thru dos-debug
now coming back to your problem, as jhance said, u cannot do exactly what u want.
but if u still wish to store data on tape, i have one idea....
you can connect the tape recorder thrusound card's line-in socket and then write a program to output the dataformat thru it which will be recorded.
and another piece of code will then recover back the data from the tape when connected in reverse way...
you may need to do some hard thinking and experimenting on this...but i think this can be done...
waiting for others to comment...
Can't be done, so I support jhance and kiranghag.
You won't be able to connect the two because the cassette won't even make it trough the handshake (wich negotiates maximum speed etc)
btw. "Anyone ever played with this before?"
yep, just before I found out that it couldn't be done!! Then I stopped.
LucF
You won't be able to connect the two because the cassette won't even make it trough the handshake (wich negotiates maximum speed etc)
btw. "Anyone ever played with this before?"
yep, just before I found out that it couldn't be done!! Then I stopped.
LucF
>Can't be done, so I support jhance and kiranghag.
>You won't be able to connect the two because the cassette won't even make it trough >the handshake (wich negotiates maximum speed etc)
you set up two pc's with a line in between to handle the connection protocol. Once established, record the sound with a line tap. For reconstruction reverse the process.
you can even set the connection speed with at commands if the recorder is not good enough quality.
At leas one hacker used this technique to capture login info.
Not very practical, but not impossible.
>You won't be able to connect the two because the cassette won't even make it trough >the handshake (wich negotiates maximum speed etc)
you set up two pc's with a line in between to handle the connection protocol. Once established, record the sound with a line tap. For reconstruction reverse the process.
you can even set the connection speed with at commands if the recorder is not good enough quality.
At leas one hacker used this technique to capture login info.
Not very practical, but not impossible.
public, please read the question:
>I would also like to be able to do the reverse process.<
Now, how would you like to do that, even if the recording is possible.
>you can even set the connection speed with at commands if the recorder is not good enough quality.
And how would that hacker do that without anyone notice it (like sitting behind the computer) I think he would have chosen a key-logger instead, easier and more effective.
>At leas one hacker used this technique to capture login info.
Not with a tape recorder, I can assure you that!
>I would also like to be able to do the reverse process.<
Now, how would you like to do that, even if the recording is possible.
>you can even set the connection speed with at commands if the recorder is not good enough quality.
And how would that hacker do that without anyone notice it (like sitting behind the computer) I think he would have chosen a key-logger instead, easier and more effective.
>At leas one hacker used this technique to capture login info.
Not with a tape recorder, I can assure you that!
>At leas one hacker used this technique to capture login info.
You're talking about DIFFERENT problems here.
The hacker has the leisure of being able to do a STATIC ANALYSIS of the data that is captured. While I agree that a tape recorder is not suitable for this work, a digitized recording of the phone line could be analyzed after the fact and the data reconstructed. Actually, this is not that difficult.
The problem posed in this question is a DYNAMIC converstation between a "real" modem and a recording device. That is what is being stated as not possible.
You're talking about DIFFERENT problems here.
The hacker has the leisure of being able to do a STATIC ANALYSIS of the data that is captured. While I agree that a tape recorder is not suitable for this work, a digitized recording of the phone line could be analyzed after the fact and the data reconstructed. Actually, this is not that difficult.
The problem posed in this question is a DYNAMIC converstation between a "real" modem and a recording device. That is what is being stated as not possible.
>The problem posed in this question is a DYNAMIC converstation between a "real" >modem and a recording device.
does not have to be. One can setup two modems and a line tap recording device for both the recording and the reconstruction.
>At leas one hacker used this technique to capture login info.
>Not with a tape recorder, I can assure you that!
he did precisely that!!
does not have to be. One can setup two modems and a line tap recording device for both the recording and the reconstruction.
>At leas one hacker used this technique to capture login info.
>Not with a tape recorder, I can assure you that!
he did precisely that!!
I'd say points to jhance. This is a clear case of "No you can't do that" IMO
LucF
LucF
Huh?
just connect a phone cable to two pc's with a modem, tap into the line and record the sound. You can start recording after the training completes, and start the reconstruction the same way. You will need a pretty good recorder with at least 40dB SNR and good phase linearity.
Would it not be simpler just to record the data on a cd at about 10c ea?