Dictaphone belts replaced the dictation cylinder during the 1940s.
Sound was embossed by a needle onto a loop of acetate-type soft-surface
material that looks like film. Similar but usually incompatible systems
seem to have been used by the government somewhat earlier.
During the late 1950s, the same design was used with sheets of
magnetic film which looks like a wide loop of audio tape. A recording
head was substituted for the embossing needle. Dictaphone was joined
in this marketplace by IBM and Peirce, each offering non-compatible
products. IBM also made them in two sizes, some of which won't work
on other machines in its line. These products phase out as the cassette
enters.
Blue Dictaphone belt
IBM belt
The translucent embossed belts stiffen as they age and should
be made softer before being copied so they can track better. Some
are of a slightly smaller diameter and will split if forced onto
the wrong mandrel.
BASIC COSTS: Perfect belts cost $ 50 to master to hard disc. I seldom encounter perfect belts.
ADDITIONAL SERVICES: REPAIRS: The most common problem, affecting
about 90% of those I've worked on, is that the embossing needle
or magnetic recording tape head usually shifts slightly during the
start-stop process when they were first recorded. Adjusting for
the problems these introduce requires a rehearsal with the tracking
adjustment control before copying. This adds about $ 50 per belt.
Though belts seem to shrink as they age, the feed screw driving
the playback head is not adjustible. I usually have to stop recording,
make adjustments, then start again, then edit the segments together.
Noises louder than the desired signal are usually present each time
the machine was started and stoped. I remove most of these bangs
by hand editing. Belts cost $ 150- 200 each to make a reasonable-
sounding listening copy.
Occassionally belts were stapled to the letters produced from
them and/or were squeezed flat in file drawers, creasing them and
creating a thump during playback which cannot always be removed.
The creases have to be softened before they can be put onto the
playback machine; if not, the belt splits and may be unrepairable.
Suppelizing them is an additional step- about $ 35. This takes about
a week per belt.
It was common for them to have identifying characters written on
the recorded surface with a china pencil. The marks theis leave
turns stiff and dry with age and will crunch each revolution. I
remove this as part of the preparation and cleaing process and copy
the data to the belt's inner side.
Four to five belts fit on a CD or cassette at $ 30 for the first
one, $ 20 for each additional.
smolians@erols.com Phone:301-694-5134
Logo drawing by Steve Stiles
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