Was it possible to send data over the phone-line without a modem?
- Was it possible to send data over the phone-line without a modem, either by connecting computers directly to the phone line, or, by connecting cassette-recorders/players directly to the phone line
- It must not require the use of a commercially available modem, but allow only a bit of extra wiring and maybe some resistors, and, or, audio-speaker and microphone .
- This is for the scenario where two people may want to share a program or data, and they don't want to waste money on the modem .
- I'm assuming the answer is no, or else people would not have bothered buying modems.
I suspect that either it may have worked for some computers and phone-lines, or, that it may have been easy for the computer manufacturers to design the specifications so it would function well without a modem, however, I suspect it was strongly discouraged in order to avoid damage to computers or to phone-lines :
- Only commercially available modems were legally certified to be connected to the phone-line, not the computers themselves, to prevent people damaging the line .
- And connecting a computer straight to the phone line may risk damaging not only the line, but also the computer .
- It must not require the use of a commercially available modem, and only a bit of extra wiring and maybe some resistors .
- Initially, this question is not about the use of any external memory devices like cassette-recorders etc.
- Or if required, this question is about computers that had access to cassette-tape-recorders, not disk-drives, but information about disk-drive machines may also be useful.
- For the common affordable home-computers in the years approximately 1978 - 1984 (a few years before, or after, is ok)
- NOTE - By plugging the cable straight from the transmitting computer and into the telephone, the cable that the transmitting computer normally used to save to cassette-tape, to the microphone-jack of the telephone (did that exist?).
- Or, by attaching an audio-speaker to the cable that the transmitting computer normally used to save to cassette-tape, and then placing that audio-speaker next to the telephone-microphone.
- (Theoretically, could you just have left a program on a cassette-tape-answering-machine, unless there were copyright problems in those days, or data quality loss because of the cassette tape)