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I know that there are tape backup systems available. I do not know how they work.

Can I use an audio tape recorder and audio tapes (like the 60/90 minute kind) and backup data somehow? (Pardon my n00bness, I've never done tape backups before.)

J Diggs
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    It might be possible – old PCs like C64 used audio tapes as [primary storage mechanism](http://en.wikipedia.org/wiki/Commodore_Datasette) – but I doubt it's possible to reliably store large amounts of data on a medium designed for audio. – u1686_grawity Mar 03 '13 at 15:49
  • @grawity: You were faster, but same Link ;) – mpy Mar 03 '13 at 15:55
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    Also in early 90s there was a popular tape backup system for PC using home VCR - http://en.wikipedia.org/wiki/ArVid 3hr tape would hold about 2Gb of uncomressed data. – Alex P. Mar 03 '13 at 16:11
  • Its my understanding Windows 7 does not support this tape backups. So even if this were possible the operating system your using wouldn't support it. – Ramhound Mar 03 '13 at 17:43
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    Eeew! just eeew! Shades O' Radio Shack TRS-80. Low quality, unreliable storage for a negligible amount of data, not worth even considering in this day and age. Yes, I've been there, no need to revisit it except for historical interest. There's a reason we moved to floppy disks and QIC tapes. Let's resurrect the old analog phone modem where you dropped the handset into the cradle. 300 baud anyone? – Fiasco Labs Mar 03 '13 at 17:57
  • **ATTN people - I had old tapes lying around - this was meant to be kinda for fun, just interesting to see if it'd actually work. thanks** – J Diggs Mar 05 '13 at 22:59
  • I'm also looking into this for fun. Just speculating: probably using 56K baud modems to help could get over 18MB per channel per side on a 90 minute tape, resulting in over 72MB on a 90 minute tape. 48MB on a 60 minute tape. Two synchronized modems, one per channel (left and right), might be the ideal solution not to play/record the whole tape twice. Already implemented solutions like what I described, I haven't yet found. – Pedro Palhoto Aug 16 '14 at 01:23
  • BTW, since audio tapes have a higher frequency range (20-20000Hz) than phone lines (300-3000Hz), developing a better encoding scheme than 56K should be possible, hence increasing overall data storage beyond 100MB on a regular compact cassette. – Pedro Palhoto Aug 17 '14 at 12:53

3 Answers3

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You can and that was very common in the 80th: Datasette (Wikipedia), but nowadays you won't be satisfied with a storage capacity in the order of 1MB. For a review of modern Tape Storage format, also see Wikipedia.

mpy
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  • Holy crap! An Audiocassette might store 1Mb of data. I remember those days. I don't remember anything resembling that capacity. Though, I guess materials must have improved a lot since then. – killermist Mar 03 '13 at 23:26
  • @killermist: I wrote "in the order of" ;) According to cited article "Datasettes could typically store about 100 kByte per 30 minute side. The use of turbo tape and other fast loaders increased this number to roughly 1000 kByte." – mpy Mar 04 '13 at 10:26
  • Not related to the topic by much, but I remember a "high speed poke" that could be done to bump the CPU speed on the COCO2. With it, you could write faster... but FAR less reliably. And if you were able to read (at all), you could only read it back again at high speed, low speed wouldn't recognize the data at all. – killermist Mar 04 '13 at 18:03
  • @killermist A lot of the limitation was the fixed tape speed and the limited processing ability of machines in question. With a modern system and a good-quality audio encoder/decoder chip you can push it all the way up to... 2MB... Hardly worth the effort. Could probably do better with digital encoding using purpose-built hardware. There were attempts at digitally encoded cassettes to compete with CDs back in the day that stored about 600MB of data. But that never took off. – Perkins Nov 14 '22 at 23:47
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Noooooo!!!

When I was starting out on my first computers back in the 1980's this is exactly what we did.

But programs were around 16-32 kB at the very most - yes that's kilo not even mega, certainly not giga!!

And, the backups failed to restore as often as not.

And, it took AGES to both backup and restore.

These days, disk space is very cheap and even Internet based storage is fairly cheap. So use those for backups. Keep at least 2 backups of all data and they must be both automatic and located in at least 2 different locations. Don't keep all backups onsite - fire, theft, etc. will see you loose all of your backups.

Personally, I have one backup to another machine locally in the house and a second to servers in the US (I'm in the UK). Oh, backups of data should also be locally encrypted as well. For reference, I use a tool called CrashPlan.

Great question though, welcome to SuperUser.

Julian Knight
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Can you? Yes.

Is it worth the effort? Not any more.

Back in the 1980s it was a somewhat common method for software distribution and backup for home computers.

But, if you assume that your tape recorder can reliably maintain enough fidelity to duplicate the signal of a much more modern 56K modem (which would need a top quality recorder and a top quality tape) then you're looking at, at most, about 25MB per hour of tape. And probably more like 25MB on a 90 minute by the time you add in sufficient error correction data since, unlike a modem, you can't just request a retransmit.

Now... If you go digital with your tape (say with an old DAT recorder) and don't mind modifying the hardware a bit then you're looking at about the same data density as an audio CD. So about 600MB. But those tapes will be more expensive.

If you're going to go to the trouble of building custom hardware, one thing I remember hearing about (but never actually saw in person) was using VHS cassettes. With proper configuration those can push 2Mbits/s. So a gigabyte or two per tape. That might actually be approaching the point where it's worth the effort these days... Except that you can just buy a DVD drive for twice that much space and disks are cheaper than tapes now.

So if you're looking for a project to teach yourself advanced electronics then building a backup tape system that uses consumer VHS cassettes might not be a total waste of your time if you have a bunch of old tapes lying around. But, even when this question was first asked, there were cheaper options available if you were buying new.

Perkins
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