Griffin & Tatlock "Microdeaf" Vacuum Tube Hearing Aid
This table model or box style vacuum tube hearing aid is marked
Microdeaf Hearing Aid and is signed Griffin & Tatlock, 19 Cheetham Hill
Road, Manchester.
The date of manufacture is unknown, but it is very
similar to other hearing aids of the same style manufactured in the late
1930s. This style of hearing aid had self-contained batteries and was
made to resemble the box cameras of the era.
The dimension were 5 13/16” high by 4 15/16” wide by 4¼” deep with a
weight of almost 2 lbs. without batteries. The "A" and "B" batteries, of
unknown type, fitted into a compartment that took up half of the
internal volume of the hearing aid.
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The microphone was mounted on one side (top picture bottom center)
and the volume control around the corner on an adjacent side (top
center). The earphone jack was to the right of the volume control knob.
This hearing aid could be set on a table or carried by hand. It
had an earphone that was worn over the head with a headband. (The
earphone is shown here but the headband is now missing.)
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The hearing aid used two miniature
vacuum tubes (top center). A large capacitor is beside them in the
corner (top right). The back of the microphone is at the left. The battery compartment
is at the front. The battery compartment door was held
closed by brass clips on each side of the box.
Griffin & Tatlock were manufacturers of scientific and laboratory
equipment and it is not known whether or not they produced any other
hearing aid models. This is the only one we have encountered. |
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A close up of the front side of the earphone. |
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A close up of the back side of the earphone. Also, notice the interesting
arrangement of the earphone plug. There was one male pin and one female
socket on the plug (right) and a corresponding female socket and male
pin on the hearing aid to plug it into. (You can see the lone male pin
sticking out in the top picture to the right of the volume control.)
This curious pin arrangement was common on English hearing aids of this
period.
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