Isn't the issue the rate of change of the temperature of the baseplate?
 
The minimum storage temperatures for most components is -65 C and the SAW filters are -40 C.
 
73,
 
John
KD6OZH
----- Original Message -----
From: Dick Jansson-rr
To: [email protected] ; 'John B. Stephensen'
Cc: 'David Smith' ; 'Dave Black (Work)' ; 'Dave Black (Home)' ; [email protected] ; 'Samsonoff@Mac. Com' ; 'Juan.Rivera (Work)'
Sent: Saturday, July 28, 2007 18:32 UTC
Subject: RE: [eagle] Receiver Spec vs. ATP, a few Suggestions and a Question or Two

Juan:

 

I do not know how you can be concerned with storage temperatures of -60C when you have just soldered a PCB with temperatures of from two to a a few hundred degrees! It seems to me that the stress of soldering would vastly exceed those of a low storage temperature. The thermal excursions of soldering considerably exceed those of the storage situation.

 

73,

Dick Jansson, KD1K

[email protected]

[email protected]

 

 

From: [email protected] [mailto:[email protected]] On Behalf Of Juan Rivera
Sent: Saturday, 28 July, 2007 05.23
To: 'John B. Stephensen'
Cc: David Smith; Dave Black (Work); Dave Black (Home); [email protected]; Samsonoff@Mac. Com; Juan.Rivera (Work)
Subject: [eagle] Receiver Spec vs. ATP, a few Suggestions and a Question or Two

 

John,

 

        (snip)

 

I also take issue with the -60C minimum power-down temperature.  I think this is unrealistic just from a CTE mismatch perspective.  The reliability of anything subjected to that wide a temperature spread is going to suffer.  A way must be found to raise that temperature.

 

(snip)

73,

 

Juan WA6HTP