Fred Ring No. 3 Hearing Aid Battery
The Fred Ring No. 3 hearing aid battery was a 4.5-volt battery used in carbon hearing aids in the
late 1920s and the early
1930s.
The Fred Ring No. 3 carbon-zinc battery weighed 11.8 oz (334 g), and measured
4" high
by 3⅛" wide by 1" thick (10.2 x 7.9 x 2.6 cm).
The label looks like it was put on a generic battery made by an
unknown manufacturer
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Top view of the Fred Ring No. 3 hearing aid battery showing the unusual
arrangement of not two, but three battery terminals. From the left they
are labeled -4˝, -3, and +. Presumably, if you didn't need all the power
available (4˝ volts), you could plug into the 3 volt socket. If you needed more
power, you plugged into the 4˝ volt
socket and had increased volume. However, there is a mystery associated with this battery.
Since
the three cells had to be wired in series (to get the 4˝ volts), if you
used the 3-volt connection, you'd use up the first two cells, and would thus
waste the third cell. The only other battery with this two-voltage
arrangement of which I know was the
Acousticon No.
2B. |
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