[ARC5] Crystal aging

[Bruce Long]

Sorry Kennth for sending this email originally just to you instead of the group   bruce


  
with respect to HF  I discovered to my surprise some small bottle rust 
removing potions available at the big orange box are actually dilute HF 
solutions.  They work really well for me.

I am also very happy to
 see this discussion of the important of WW2 quartz crystal technology- 
having been previously employed at Piezo Crystal Company, McCoy 
electronics and Bliely- the latter as a consultant.

The huge 
expansion of the quartz crystal industry in the USA was in my opinion a 
very important aspect of the American war effort and is not widely 
understood or recognized.  IIRC the war time expansion when from fewer 
than 10 very small pre-war crystal companies that catered to the amateur
 and custom experimental market to well over 300 companies at the peak 
manufacturing what was at the time an extremely high tech,
 precision product.