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RE: [AV Media Matters] Storage of playback equipment

At VidiPax we have a museum of equipment in addition to our production
equipment. I am not sure that I can give any "answers" but can let you
know our experiences.  I will not talk about storage as much as the
issue of the equipment itself.

First of all some of our equipment is VERY old - as in pre-electronic.
The conservation of these artifacts is a bit different then the majoriy
of the collection.  We have literally hundreds of machines and they vary
dramatically in size and complexity from the huge Ampex ACR 25 which is
about 10' long x 7' high x 3 feet deep and weighs over 1000 lbs., to
tiny portable "spy" tape recorders. So, the care of these machines is
really quite different depending on the technology.

In some cases we try to keep the equipment in running operation so that
we can demonstrate the technology.  For example we have several Chicago
Webster wire recorders that we use for this purpose.  The machines that
we do this with are generally machines that are less rare in the
collection.  The reason is a practical one - the less rare ones are
easier to find, and therefore maintain by having a few parts machines in
the back room that we canabalize when necessary.  That is clearly not
the case with prototype machines or extremely rare machines - of which
we also have many.  In most cases we make no attempt with this catagory
machine to keep them workable.  There are several reasons for this - but
the primary ones being our concern about damaging the authenticity of
the artifiact with putting in non-period parts or literally burning them
up - don't laugh - we always have a halon fire estinguisher around when
we power an old machine up for the first time. We also do not attempt to
even try to power some of the equipment for the same reasons.  If we do
choose to power them up, we do it VERY carefully.

There are different catagories of component failure.  Some parts, like
those fabricated out of rubber, fail just due to age.  Mechanical
assemblies fall into this catagory - with metal parts that oxidize and
fail or wear - that usually requires the services of a machine shop.
Wire insulation also falls into this catagory - some insulation is woven
cloth, others are rubber, and plastics including some pvc.  Believe it
or not, you CAN still get cloth insulated wire - but some of the earlier
plastics are now impossible (they are made of nasty banned stuff). When
insulation fails, you often get a short when two or more wires make
contact - definately not a pretty sight.  And it happens frequently -
even with machines that are used in production because heat will cause
some insulation to fail - get dry and literally flake off of the wire.
Other insulation gets greasy and sort of melts off the wire- and in high
voltage circuit areas it is easy to get an arc as the insulation starts
to fail.

Other components fail - capacitors - particularly electrolytic are a
problem, and resistors can burn up rather easily. Usually failures of
these types in old equipment are multiple - meaning that when a
capacitor fails it usually takes out other components in the circut with
them - and some of them may be located in other boards or locations - so
it becomes a bit of a treasure hunt.  In the treasure hunt department
there is the issue of finding equivalent components.  Oddly, this is
often not the biggest problem with older equipment because basic
"building block" components are still readily available - even if they
are not accurate historically.  This will NOT be the case when the
current technology becomes old because more modern equipment have custom
multi-function IC's which will be impossible to source and replace.

The issue of safety and technical knowlege is important to discuss.
Even if you have the parts - can you find someone who is skilled in
debugging 50 year old machines - some made before they were born? This
is not a widely available skill set. Older machines were not as safe as
current technology, and you can get zapped and really feel it -
interlocks and other safety devices did not exist - and basically you
are on your own - so you really have to be careful.

Finally there is the issue of documentation.  Many of the machines that
we have are without technical documentation.  This may be because it was
lost or was never owned by the original owner.  Other then their value
as ephemera - the user manuals are pretty useless - we need the service
manuals - and for some machines - such as ones where the company went
out of business - they are virtually impossible to get.  For these cases
you need an electronic technician who has a good enough knowlege of
older style electronics to essentially figure out what is going on in
order to try to make a machine work.  While this is fairly straight
forward with a small audio or wire recorder, it becomes quite another
matter with a complex machine like a VR-1000 (the first videotape
recorder.  On the positive side - the machines were really a great deal
simpler then those available now - so the circuit design is more
straight forward.  In any event - it is a challenge!

Jim Lindner
The Full Service Magnetic Media Restoration Company
212-563-1999 ext. 102
See our web site at www.vidipax.com

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