I was arguing with my father about how unlikely it was for the magnetic tapes to erase after a certain period of time. Does anyone know roughly how long it takes VHS tapes to automatically erase if it's played on an occasional basis? He said 20 years. I thought much longer. He's been paranoid about his 20-25 year old VHS tapes and quickly converted them to DVD. Is he worrying too soon? Should he even be worried at all?

The old tapes may yet outlive the recordable DVDs! So hang on to those tapes just in case.

I have old VHS tapes from late '70s, some 30+ years old now, that play fine. Only issue I've had is the leader tape on a few fatiguing at the point it's anchored to the take up hub, and breaking. Have to take the tape apart and re-affix it to the hub and all's well.

Unlikely to erase but the tape itself could degrade and become unplayable at some point, I haven't found many like that yet unless they were stored very poorly.

DVD-r isn't a good solution, I have had quite a few of them (and CD's) become unplayable in a relatively short period of time, far shorter than tape, largely due to the stick on labels that were popular a decade or so ago.

Unlikely to erase but the tape itself could degrade and become unplayable at some point, I haven't found many like that yet unless they were stored very poorly.

DVD-r isn't a good solution, I have had quite a few of them (and CD's) become unplayable in a relatively short period of time, far shorter than tape, largely due to the stick on labels that were popular a decade or so ago.

I knew it was more of an "old wives' tale" than anything else, probably just another plea to get everyone to "modernize."

Tape does not generally erase itself magnetically beyond a possible loss of maybe 3dB due to magnetic domains that weren't firmly aligned, going back to random orientation.

The Cartrivision folks studied this very carefully, as they intended to use a thermal contact printing process for duplicating tapes, and they needed to know what processing was necessary to get maximum transfer. The thermal transfer was like an instantaneous life test. They found that whatever temperature/time profile they used (within reason) the maximum degradation was 3 dB.

Degradation of tape is generally due to chemical/mechanical deterioration, so storage conditions are important, as are the formulation of the plastic base and the binders that hold the oxide on. The oxide itself, however, retains its magnetism well, as far as I know.

I have noticed 8mm camcorder tapes developing increasing dropouts after 20 years, so that would be a reason to make copies.

Tape does not generally erase itself magnetically beyond a possible loss of maybe 3dB due to magnetic domains that weren't firmly aligned, going back to random orientation.

The Cartrivision folks studied this very carefully, as they intended to use a thermal contact printing process for duplicating tapes, and they needed to know what processing was necessary to get maximum transfer. The thermal transfer was like an instantaneous life test. They found that whatever temperature/time profile they used (within reason) the maximum degradation was 3 dB.

Degradation of tape is generally due to chemical/mechanical deterioration, so storage conditions are important, as are the formulation of the plastic base and the binders that hold the oxide on. The oxide itself, however, retains its magnetism well, as far as I know.

I have noticed 8mm camcorder tapes developing increasing dropouts after 20 years, so that would be a reason to make copies.

Yes, I know for a fact that the 8mm tapes will deteriorate after several decades. My grandmother's tapes from when my mother was young have been severely damaged so my father advised her to make them into DVD's, which can be done at many electronics stores for a small price.

Unlikely to erase but the tape itself could degrade and become unplayable at some point, I haven't found many like that yet unless they were stored very poorly.

DVD-r isn't a good solution, I have had quite a few of them (and CD's) become unplayable in a relatively short period of time, far shorter than tape, largely due to the stick on labels that were popular a decade or so ago.

What about gold lacquer DVD-ROM's? They have a rated archival life of 100 years.

Hello..Fascination overcomes me with this thread. I have wondered this myself

My father and mother have VHS tapes, taken on an '86ish Hitachi camcorder in 86-88, which exhibit virtually ZERO degradation when viewed today....However, there are a pile of VHS tapes taken in '84 or so on an unknown machine owned by my great-uncle, which are quite lousy and are barely viewable.

The good tapes: TDK 'hi-fi' standard
The bad: JVC archival, ironically.

Which leads me to believe that the machine which recorded the programme originally, is the most important factor.

Which leads me to believe that the machine which recorded the programme originally, is the most important factor. Without seeing the symptom, one common cause of playback problems is alignment differences between the recording machine and the one playing back. This interchangeability problem will show up especially on the slower speeds. At EP speed (aka SLP) the track width the heads lay down is 19 microns wide (1 micron is 1/1000 of a millimeter), so there's not a lot of room for error.

Most of the tapes in question were made on 2head camcorder machines, but a few were hifi sound and 4head. In any event, the misalignment of which you speak seems likely....it's rolling noise bar interference which causes the audio buzz and all....some segments are fine, and some are just shot....and the tape itself doesnt appear too battered at these points...so....this is one of the reasons i chimed into the thread.

I've actually mis-aligned a VCR to a particular tape just to get a decent copy. Then re-aligned the playing VCR afterward. Not recommended if you don't know how to align the tape path, mainly the cylinder entry and exit guides.

interesting, Ed...That reminds me of something in the audio world; where a user would adjust vertical tracking angle of his stylus to accommadate a particular label or pressing....in an effort to tame sibilance/splosives.

I've aligned the playback deck to the tape with audio cassettes and reel to reel tapes too; switch to mono, listen closely and adjust head azimuth for maximum treble then switch back to stereo, to get a decent copy with all the highs (and phase of L-R channels pretty close) to copy to a CD-R.

I'm not well versed on this but something I've noticed is that many home-recorded tapes that I've found tend to have bad audio, as if it is misaligned. Tape in general seems to have an incredible lifetime. I have some early 80s Beta that looks as good as live, and have mentioned before the paper-backed audio tape I have that must be from around 1950. Still sound like it was just recorded.

One way I've heard of VHS tapes erasing themselves with time is when some one would punch a hole in a VHS cassette to be able to record S-VHS on it using a pre S-VHS-ET recorder. This supposedly made good recordings that would only last about a month before becoming unwatchable.

Tom C.

The magnetism on a particle used in a magnetic medium lasts forever. It is a single domain with a permanent magnetic charge. The signal on a recorded magnetic medium, however, depends solely on the pattern of the billions of magnetic particles. Recording rearranges their magnetic (not physical) orientation to a particular pattern. Erasing randomizes their magnetic orientation so that no pattern is evident.

On another subject in this thread, the protective lacquer on any optical disc makes no difference what color it is, as long as it seals the edges of the disc and prevents air or moisture from reaching the mirror layer. Sputtered gold as a mirror layer does not oxidize, so it is superior to silver alloys or aluminum only in case the lacquer is defective and allows sulphur-bearing air to reach the mirror layer. In other words, gold is superior only for CD-R discs that might be damaged or defective. Gold reflects less than silver alloy and must be relatively thick in order not to modulate the reflected laser output.

For DVD use, gold is inferior to silver alloys in writable optical discs because the specifications for DVD+/-R were designed for silver alloy. I have never found a DVD+/-R disc with a gold mirror layer to have initial PIE errors lower than about 50, while the best silver alloy DVD discs could have PIE errors in the low single digits.

The average expected lifetime of a well recorded DVD+/-R disc is about 52 years according to the most accurate environmental tests done on them. 95% would be readable after 39 years with proper storage. CD-Rs using phthalocyanine dye would be readable in 125 years. The weak point for both discs is the dye used, not the mirror layer. The quotes of 100/300 years of lifetime expectancy for DVD/CD recordable discs are bogus because the testing was too short and used only a single stress factor--heat--instead of the double-stress tests using both heat and humidity.

Just like audio tape it will pretty much live indefinitely, or until the material degrades. Audio tapes need to be baked to alleviate the moisture and it does something to the material to allow that one last play to transfer whats on em safley....ive done it to 40-50 year old tapes with no issue...and no quality degradation. There is still wire recorders out there too...with material still on teh wire from 70-80+ years ago!

Audio tapes do not need "baking" or any other special treatment unless they used a particular hydroscopic polyurethane in their binder formulations. A good portion of Ampex and Agfa production suffered from this instability, and some 3M production also used the same binder. BASF, Maxell, and TDK tapes do not suffer from the same problem and should never be "baked" prior to playing them.

I think the oldest VHs Tapes I Have are a couple from 1978 and 1979. have made copys of them on other vhs tape and dvd-r. Both tapes play back just fine. I use DVD mainly to play them on my laptop.one tape is Elvis in concert. One of the last concerts he did, with the original 1970's commercials. "At GE we never stop inventing the lightbulb"

Audio tapes do not need "baking" or any other special treatment unless they used a particular hydroscopic polyurethane in their binder formulations. A good portion of Ampex and Agfa production suffered from this instability, and some 3M production also used the same binder. BASF, Maxell, and TDK tapes do not suffer from the same problem and should never be "baked" prior to playing them.

Really? I have transferred tapes from the 50's up to the 80s, and ive had to bake em all. Every time I tried to play one, be it 1/2" up to 2", and 2" especially i have nothing but shedding, and more so binding problems....the tape machine just stops, literally. After baking at low temp 130 deg in a food dehydrator for 6-8 hours, plays fine, almost no shed, and no binding, done and done. Then again I canot remember what brands they were. defiantly remember doing ampex stuff, but i dunno bout other brands. It doesnt hurt the tape to bake it

It may very well hurt the tape if the tape is baked and doesn't need it to drive moisture out. It all depends on the particular chemistry the manufacturer used to make the tape. Cross-linking, base pre-treatment, surface treatment, varying lubricants, double-calendering, and a number of other manufacturing techniques may respond differently when a tape is subjected to heat beyond that for which it was intended. Certainly expansion and contraction put extra stresses on the tape pack when it is heated beyond 90 degrees F.

At BASF we put thermo stickers in all our containers shipped during summer months and paid extra to make sure no tapes were subjected to more than 95degrees F. If they were, the shipper paid for the container, and we threw the tape out.