[ARC5] X-1 Radios and the AN/ARC-7

[Mike Morrow]

> For the original X-1's ... there is a view of the right sub-console
> of X-1 S/N 6063 which has a switch marked "ARC-5 Bands 1 2 3 4 5."

Very odd. That would be inconsistent with the VHF AN/ARC-5, which has four
channels designated A, B, C, D.

> Interestingly enough there is one photo of one of the original X-1's,
> 6062, during assembly that shows a panel on the right front side
> marked "ARC-7", with a knob marked "Increase Volume",  and a switch
> marked "Power On." ... The S/N 6062 ARC-7 controls were in the same
> location as the ARC-5 "bandswitch" on S/N 6063.    

The AN/ARC-7 is very likely the set that was originally intended.  But
it seems never to have never been ordered for actual deployment.  It is
described in "Graphic Survey of Radio and Radar Equipment Used By The
Army Air Forces", Section 2, 1 March 1945:

--------- START QUOTE ----------

Radio Set AN/ARC-7 is a single channel VHF receiver and transmitter
to be installed in gliders for communication with tow planes and
ground stations.  It is designed to be operable on any frequency in
the frequency range of Radio Set SCR-522 (100 to 156 Mc.).  It is
capable of five hours continuous operation, assuming 5 per cent
transmitting time, without without recharging the glider battery,
and it is also capable of operation over a distance of 30 miles,
air-ground, from an altitude of 1,000 feet, when used in conjunction
with Radio Set SCR-624.

As a possibility exists that the receiver portion of the set, if
it is proved satisfactory, may be used separately as a ground receiver
with Radio Set SCR-522, the receiver is built as a separate unit,
containing its own power supply.
 
POWER INPUT         24 VDC
POWER OUTPUT        0.5 WATTS
FREQUENCY           100-156 MC
TYPE OF SIGNAL      CW; MCW; VOICE
RANGE               AIR TO GROUND-120 MILES AT 10,000 FEET

Radio Transmitter   T-XA-28A/ARC-7(XA-2)     12"x7"x7"
Radio Receiver      R-XA-30A/ARC-7(XA-2)     14"x7"x7"
Control Box         C-XA-48A/ARC-7(XA-2)

--------- END QUOTE ----------

Total weight is about 25 pounds, and 24 tubes are used.  The
receiver is larger than a SCR-274-N transmitter (the side
flanges that appear to engage a FT-234-A shock mount are
included in dimensions given above).  It appears to use a
unique small dynamotor (not a DM-32-A) that no doubt supplies
the transmitter as well.  The control box has only audio jacks,
volume control, and power switch.

It is very likely that the AN/ARC-7 was initially to have equiped
the X-1.  If the AN/ARC-7 completed the development and test
phase, it was never ordered into production and wasn't available.
It should have been fully adequate for the X-1.  I wonder if any
AN/ARC-7 components have survived anywhere.

Mike / KK5F