[ARC5] Calibration Crystal Variations

[David Stinson]

One thing I love about our mil radios:
We keep discovering new and interesting things.
A box, containing a big pile of  70 or 80 Command Set transmitter
calibration crystals, that's been buried in my "cave" for ten years,
finally surfaced a few days ago.  This pile- all save one on 2500 or 3500 
KC-
seems to have been tested at Wright Field between 1949 and 1954,
since they are all stamped similar to: "9 OH 10 51" or "9 OH 7 49"
using white ink along the long axis.
Most (not all) were made by General Electric, for either A.R.C., W.E,
or Stromberg.  Some are just marked "made by General Electric."
Many are marked with a large U.S. Navy inspection anchor, and some with a 
small one.
Some are marked with a triangle with a "T" in it (for "tested"),
and some with a circle with a "T" in it.  Some have the "T" on the
envelope skirt in silver ink, some on the bottom of the center
index pin in orange ink.

Here are some representative examples of large fractions of the pile:

Made by GE.  No anchor, No "T" mark.

Made by GE.  Large Anchor, No "T".

By GE for Western Electric, all 3500KC, marked:
 "US ARMY SIGNAL CORPS DC-8-C"

By GE for Aircraft Radio Corporation.
(4) 2500 KC, orange circled-T mark on index pins
(18) 3500 KC, silver triangle-T mark on base.
(1) 3500 KC with large Navy anchor and triangle-T on base.

By GE for Stromberg Carlson.
(1) 2500 KC with large anchor and silver triangle-T on base.
(6) 3500 KC no anchor and no "T" mark.
(5) 3500 KC large anchor, with triangle- or circle-T on base.
(7) 3500 KC small anchor, triangle-T on base.

By Aircraft Accessories Corp., Dayton, Ohio Division
(5) 3500 KC
Marked "US ARMY SIGNAL CORPS DC-8-L"
Marked "Resonator only" in white ink along long axis.
Marked with small, square orange Army Sig Corps inspection stamp.

By Western Electric
(3) 3500 KC
Marked "US ARMY SIGNAL CORPS DC-8-D"
The WE markings were sloppy- indifferently applied.

Odd-Ball units:

(2) Army-marked 3500 KC units, marked both:
"Made by Aircraft Accessories Corp. Dayton Ohio Division"
 and
"Made by Western Electric, New York."

(1) DC-8 3500 KC marked:
ORDER N38**-29946
E.B. Lewis Co., East Hartford
For Navy Department Bu. Aero.
Winged "80" inspection marks.

Army By GE for Western Electric marked "3500.00"

GE for Stromberg with large Navy anchor in Orange.
Army By Western Electric with "square" top sholder (not rounded).

I know there's got to be a good story here someplace ;-).

73 Dave S.