Jay I assume from MRL? If so, he has a little leaf he hands out with
every test tape he sells, that is a very interesting read. In short, he
claims (and I believe it) that the tapes are very robust and that if you
read through his description you realize that it takes a very strong
magnetic field to erase a tape.
בתאריך 17/04/13 7:01 PM, ציטוט Richard L. Hess:
> Hello, Gregorio,
> In general, the magnetic record seems to be rather robust and it
> mostly decays from close encounters with magnetic fields stronger than
> the Earth's. I know of no studies that have attempted to quantify
> this, but I'm copying Jay McKnight who may know of a study and if he
> has any information, I'll post it to the list.
> So, assuming no chemical or physical degradation (which mostly affect
> tape via spacing loss across part or all of the tape) and no close
> encounters of the strong magnetic kind, the S/N decay rate would be
> minimal (I don't want to say zero, but I suspect close to it).
> We had the discussion on the Studer list about whether tape or machine
> background noise is predominant and Jay chimed in with an "it
> depends". For master tapes, generally the tape noise is predominant.
> There are times at slower speeds and narrower tracks where
> head/electronics noise would be predominant.
> As to degradation factors, I have a page I try and keep updated where
> this is discussed.
> I hope this helps a bit.
> On 2013-04-17 12:32 PM, Gregorio Garcia Karman wrote:
>> Dear members,
>> I am looking for references in the literature dealing with the study
>> of the decay of magnetic remanence as an effect of tape aging. What
>> is the expected signal-to-noise decay rate under ideal conditions
>> (i.e. no chemical degradation)? In real life, what is your experience
>> in regard to different brands / models in similar storage conditions?
>> Thanks in advance and regards
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