[ARC5] More Problems with the "VHF Primary" Myth:

[David Stinson]

The operational problems with WWII aircraft VHF sets 
lasted longer than has generally been accepted,
again proving that aircraft VHF during the war 
was "not ready for prime time"
and in no shape to "replace" any system during the conflict. 
The "crystal shortage" issue, which dogged the first half of the war,
was replaced by the "crystal aging" issue, which resulted 
in drift and activity failure.  These problems with supplying
the Air Corps with good VHF crystals continued 
past the end of the war.  

From:
IEEE Proceedings of the 35th Annual
Frequency Control Symposium, pp. 3-12, 1981
"A HISTORY OF THE QUARTZ CRYSTAL 
 INDUSTRY IN THE USA"

"...
The Ageing Problem
By the middle of 1943 the task of setting up an industry 
was complete and crystal units were being produced in numbers 
adequate to meet the demand. It was then that the second, 
and even more serious crisis confronted the crystal program. 
Reports began to filter in of extensive crystal failures both in service
 and in depot storage. The first responses to these reports ranged 
between indifference and disbelief.  However, the reports became 
more persistent and the Signal Corps Engineering Laboratories 
(SCEL) at Fort Monmouth were requested to investigate the situation.
 The progress was slow because the problem was treated as 
an academic question rather than a matter of the utmost urgency. 
Late in 1943 a telegram was received at OCSIGO 
which changed the situation. 
It read as follows:

COMMUNICATIONS EIGHTH AIR FORCE 
BASED IN BRITAIN BROKEN DOWN 
LACK OF CRYSTALS 
FIND CAUSE CURE SAME EAKER

... tests quickly confirmed the field reports. 
All crystal units failed within a few days or at most a week or two...
the ageing syndrome (was) characterized by loss of activity
 and increased frequency. 
Many theories were advanced to explain the 
phenomenon and these had to be checked out experimentally. 
Meanwhile the manufacturers were producing crystal units at
 the rate of a million per month; 
nearly all of which were destined to be useless....
The problem of ageing was especially severe in the CR-1 unit 
used by the Air Force ...

Consequently a Conference of all Crystal Manufacturers 
was called on July 11-12, 1944....
The problem was explained in detail and the proposed remedy 
was presented.... Ironically, the ageing problem might have been 
avoided had better communication existed. 
The phenomenon of ageing had been noted 
as early as October 1940 at RCA...
At home teams of GI's and civilians were trained 
to examine depot stocks of crystal units and to select out 
useable units which were often flown immediately to a war theatre. 
Later some attempts were made to salvage the defective units 
and at least one company, The Hudson American Co., 
was commissioned to do so. However most of the units 
were enclosed in phenolic plastic holders and many others 
contained brass contacts, both of which were considered unsatisfactory,
 leaving little besides the quartz blank to be salvaged. 
It soon proved to be uneconomical to salvage the units and ultimately 
millions of the unetched units were destroyed...."