[Collins] RE: {Collins} Re: 70K-2 PTO

[Dr. Gerald N. Johnson]

On Thu, 2007-11-15 at 19:29 -1000, pete wokoun, sr. wrote:
> Hi,
>  
>   Just a question from someone still learning.  Why does the leadscrew need to be isolated from the endcap?
> Isn't it grounded at the shaft end already?
>  
> Pete 

Likely the intent of the glass ball is to prevent a ground loop through
the PTO coil that might change loading as the quality of the connections
to that ground loop change. If its an open circuit all the time, then
there' no current coupling like a shorted turn. Granted the shaft is at
right angles to the coil so coupling is minimized but when you expect
the oscillator to stay within 100 Hz all day, you can't stand small
secondary effects.

McMaster-Carr has, them CRA ought to stock them. $5 per 100 in my
catalog, could sell for enough to pay for having them.

-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer