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MORE COILS |
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Small loading coils. No. 28 on the left, No. 29 on
the right. |
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MRL Telefunken Coil. |
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| Elmer related how in 1924 a radio
wholesaler named C. D. Tanner came into Elmer's store and
sold ELMER a radio. Elmer bought it because it was
very selective. No sooner was Tanner out of sight then the
bottom of the radio was off and the circuit checked. It was
a Telefunken circuit. Detail Print #58 shows the MRL No. 4
Telefunken crystal set. |
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Another work of art, and nicely preserved. How long
did this take to make? It cost two dollars in 1986, which is the
same price for which he sold the much simpler QRM coil shown on Page 1.
$2 in 1986 is $4.50 in 2018.
Elmer would have to make and sell six of these AN HOUR at
$4.50 each to
make an "average income" in 2018. That's 240 coils a week! It's no wonder he never stopped working. |
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MRL 29-A coil, part #7-193. Not to be confused with
the No. 29 Variometer, part #7-194.
This coil seems to be the one used in the MRL No. 29 variometers,
but without the inner coil. |
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Similar to the 29-A. This one may be a No. 10-A.
The coils were numbered according to the radio they went to, so the
#10 coil
went with the MRL #10 radio, described in both HB-17 and Detail
Print #34 |
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80 turn coil with taps at 10, 13, 25, 35, 45, 55, 65,
and 75.
A coil calculator shows this coil will tune from 600 kHz to 3 MHz.
Which MRL set did this go to? |
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ANOTHER MRL MYSTERY. |
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An old wooden box, painted black. |
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The inside is lined with felt. The hinges are broken
and the bottom of the clasp on the front is missing. |
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The felt has been cut and tacked into the box. On the
lid is an MRL address label. The
address is 151 Liberty St, San Francisco, CA. This places the date
between 1934 and 1938. What was so important about the contents of
this box that the owner lined it with felt? |
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These. |
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Each coil has a label stating the type of coil, a schematic
and the price. The labels were made with fountain pen ink.
The handwriting looks like Elmer Osterhoudt's handwriting. |
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The bases are repurposed vacuum tube bases
which have been cut down with a saw. Each base has two lines
cut into the bottom.
The text on the bottoms reads, "LICENSED ONLY TO EXTENT
INDICATED ON CARTON." |
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| Why the lines in the
base? There's an explanation on page 593 of the Feb 1935 issue
of |
Short Wave Craft. |
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Also in the box was this. The label says, "SHORT WAVE
CHOKE 2½ Mhy 25¢" |
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Why do these coils have the labels with the
schematics and prices on them?
Are these coils the ones that Elmer used as templates in 1936? Were
they display samples in his radio store?
Who put them into the felt-lined box, and when? |
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MRL TYPE D ANTENNA COUPLER |
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On the left is the catalog drawing for the MRL
antenna coupler. The drawing shows a plug-in coil with the antenna
coupler surrounding it. The plug-in coil is the small rectangle at
the top of the drawing, as the top projects 1/2 inch from the
antenna coupler when viewed edge on.
Included with the coupler was MRL Detail Print No. 11 which gave
more information on its construction and use.
$1.50 in the 1983 catalog, $2.50 in 1986. |
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Mabel's and Elmer's handwriting. Elmer on the right. |
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PHONE CORDS |
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Would you buy a headphone cord based on these
drawings in the catalog? I did. |
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MRL-made headset cord, assembled by Elmer in October
of 1986.
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Elmer wrote "the cords now cost twice as much, so we make our own.
Will last forever - we hope." He charged $3.75. Thirty-three
years later the cord still looks new. |
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MRL BATTERY HOLDER |
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| This drawing is from "Radio Flyer No.
23", dated 1971. It
is one of only four MRL-made items in Elmer's entire collection of
literature that is drawn in perspective. |
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| This drawing is from page F-6 of the 1972
catalog; once again, drawn in perspective. Note that
the description states "BRACKET for #10-26." There is no
item in the catalog with that part number. It refers to the
MRL No.10 and MRL No.26 All Wave Crystal Sets. |
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| Here is an actual MRL battery holder. This
photo was taken from a picture of the back of a 1970s MRL
No. 10 that was posted on ebay. It's brass bar stock, cut,
folded and drilled. |
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This one, designed to hold a 9V battery, is made of
sheet metal and dates from 1982. |
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| MRL Crystal Set #74 |
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Typical EO two dimensional drawing in the
MRL catalog. In 1970 Len Buckwalter wrote an article Mechanix Illustrated describing the construction of a
crystal radio. He mentioned MRL in the second paragraph. The
result of the article was the MRL #74 Crystal Set Kit.
Full details are found in DP-74, which is the last Detail
Print published by MRL.
Note: This is not to be confused with the MRL #1
"Original Radio" described in HB-17. |
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| An actual MRL #74 |
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| 3D perspective drawing from
Mechanix Illustrated, which can be found
here. |
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