[R-390] R-390 (Non A) For Use With CY-979A Cabinet???

[triodes at optonline.net]

 Guys,
 
Thank you for all of the comments and replies with regard to my inquiry.
 
I guess the real question here is as follows: was the CY-979A designed for use with the R-390, or only the R-390A receiver? If it was designed for use with the R-390 (non "A" version), I think we can safely assume that the engineers at the time did think through the heat load and related thermal considerations in the design of the CY-979A, so as to provide a safe operating temperature without jeopardizing the long-term reliability of the receiver.
 
Yes, the R-390 runs hot, hotter than the R-390A. But objectively, if indeed the CY-979A was designed for use with the R-390, there should be no issues.
 
Does anyone know when the CY-979A was first introduced to the military? If the introduction date was during the original R-389 or R-390 production period, that may conceivably mean something here. If it was introduced during the run of the R-390A, perhaps that would indirectly infer that it was designed for use with that receiver unit only.
 
Thanks & 73,
 
Bruce, W2XR