Heterodyne Crystal Failures Mode?

[W5EUQ]

_Excellent question Ken._  I've wondered the same thing but never took 
the time to check the schematic to see if I could analyze it to figure 
it out.  I just replaced them and went on............hmmmmm.  Now I'm 
mad at myself....  HI

In all my 50 something years of experience, plus going to Purdue for my 
BSEE, all that sometimes still doesn't allow me to figure out why 
something like this happens. 

Bottom line: it's really very simple,  someone will figure it out and 
then the rest of us will say, "that makes sense" ..... ain't life 
funny?....but we're having fun...   nuff said.....  Bob

Kenneth G. Gordon wrote:
> On 20 Jul 2006 at 21:32, Jim Flanagan wrote:
>
>   
>> Hey guys..
>> I noticed that the Het Osc crystals seem to fail fairly often in the
>> HW101. This appears particularly true for the upper 10 meter band
>> crystals.  Has there ever been a technical evaluation as to why this
>> seems to be the case?  I was curious if anyone has attempted to remove
>> the outer case of these bad crystals and resolve the problem.  Of
>> course, if the actual quartz material has been broken due to
>> shock,etc, then that is one thing.
>>     
>
> I've noticed the same thing, but have not been able to take the time to 
> investigate further.
>
> Perhaps it has to do with the fact that those are overtone crystals, and 
> there is a manufacturing problem.
>
> Further investigation is required.
>
> Ken Gordon W7EKB
>
> -----------------------------------------------------------
> Products bought, sold or traded here is the responsibility of the
> parties involved.  This list and the City of Tempe are not responsible
> for losses or misrepresentations of any kind.  Buyer beware!
>
> -----------------------------------------------------------
> This list is a public service of the City of Tempe, Arizona
> -----------------------------------------------------------
>
> Subscription control - http://www.tempe.gov/lists/control.asp?list=HEATH
> To post - HEATH at LISTSERV.TEMPE.GOV
> Archives - http://listserv.tempe.gov/archives/HEATH.html
>
>
>   

-----------------------------------------------------------
Products bought, sold or traded here is the responsibility of the
parties involved.  This list and the City of Tempe are not responsible
for losses or misrepresentations of any kind.  Buyer beware!

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.asp?list=HEATH
To post - HEATH at LISTSERV.TEMPE.GOV
Archives - http://listserv.tempe.gov/archives/HEATH.html