Philco Mark I Transistor (Body) Hearing Aid
The Philco Mark I was the first of two transistor body aids made by
Philco of Philadelphia, PA. The Mark I was first produced in 1955.
Philco manufactured these hearing aids for Montgomery-Ward Co. under the
Philco trade name.
This hearing aid was quite small for the time and measured 1¾" x
1⅝" x ½" and weighed 1¼ oz. without
the battery.
It had a chrome case and contained 3 transistors. The microphone sits
behind the 4 "star bursts" grill (lower left front).
Based on Patent No.
3030586 filed in 1955 and issued in 1962.
|
 |
Click picture for larger view |
| |
|
|
|
|
Inside view of the Philco Mark I with the front cover removed showing
the circuitry. Note the large microphone in the bottom left quadrant. |
 |
Click picture for larger view |
| |
|
|
Top view of the Philco Mark I showing the on-off/1-6 position volume control (left),
the receiver cord jack (center) and the two-position (High-Low) tone
control (right). |
 |
Click picture for larger view |
|
|
|
The Philco Mark I had a somewhat unusual plug for the receiver cord.
Instead of the two pin plug that was common (and used at the receiver
end), it used what looks like a standard audio plug, but it is slightly
bigger—just a bit over ⅛" in diameter. |
 |
Click picture for larger view |
| |
|
|
The back of the Philco Mark I. The control functions are engraved on the
back of the case behind the controls to which they refer. In the upper
left corner is inscribed "Lo-Hi-Tone" and in the upper right corner, "Vol-On-Off". |
 |
Click picture for larger view |
| |
|
|
The battery door on the Philco Mark I swung up and to the right from the
bottom right corner. This hearing aid used a 625 battery.
The clip across the front of the hearing aid could be used as a tie clip
with the hearing aid itself hidden under the tie. (One wonders how well
the microphone would pick up sounds with the tie covering the microphone
grill.)
|
 |
Click picture for larger view |
| |
|
(If a larger picture doesn't appear, you may have to
turn your pop-up blocker off)
|
|
|
