[eagle] Re: Receiver Spec vs. ATP, a few Suggestions and a Question or Two

[John B. Stephensen]

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: juan-rivera at sbcglobal.net ; 'John B. Stephensen' 
  Cc: 'David Smith' ; 'Dave Black (Work)' ; 'Dave Black (Home)' ; eagle at amsat.org ; 'Samsonoff at 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 -60°C 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

  kd1k at amsat.org 

  kd1k at arrl.net 

   

   

  From: eagle-bounces at amsat.org [mailto:eagle-bounces at amsat.org] 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); eagle at amsat.org; Samsonoff at 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
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