Mears (Medresco) Model OL-380 Conversation Tube
The Mears Model OL 380 A conversation tube was made by Mears in the
UK and was distributed to people in the UK by Medresco, the British
health service.
This model was made at least from 1949 through 1952 and likely longer
based on dated versions of this model.
The overall length of
this conversation tube is 42½". It weighs 5.2 oz.
|
 |
Click picture for larger view |
| |
 
|
| |
|
|
Close-up of the mouth of the Mears conversation tube. The diameter of
the bell is 2½". Both the bell and the earpiece are made of a beautiful
reddish plastic.
|
 |
Click picture for larger view |
| |
|
|
Side view of the bell of the Mears conversation tube. The bell is 3¼" long.
|
 |
Click picture for larger view |
| |
|
|
Close-up showing the name and model of this conversation tube. It reads,
"MEARS OL 380 A".
|
 |
Click picture for larger view |
| |
|
|
Close-up of the earpiece of the Mears OL 380 conversation tube. The
earpiece is 5½" long, while the right-angled bend is 1⅜". The earpiece
terminates in a white plastic ear tip. This ear tip can screw off for
cleaning or replacing if it broke.
A somewhat unusual feature of this conversation tube is that the
earpiece has a swivel base so you can adjust it to fit your ear without
having to "roll" the tube itself.
|
 |
Click picture for larger view |
| |
|
|
Top view of the Mears conversation tube showing the taper as the tube
goes from the bell to the earpiece.
|
 |
Click picture for larger view |
| |
|
|
Close-up showing the differences in the diameter of the tapered
conversation tube. The tube diameter going into the earpiece (upper) is
⅜" while the tube diameter going into the bell (lower) is ¾". Tapered
tubes were commonly used in conversation tubes to compress (amplify) the
sound waves as they traveled to the earpiece.
|
 |
Click picture for larger view |
| |
|
(If a larger picture doesn't appear, you may have to
turn your pop-up blocker off)
|
|
|
