Posted by
Don Wilhelm-4 on
Apr 25, 2012; 11:44pm
URL: http://elecraft.85.s1.nabble.com/New-KAT500-pics-from-the-Visalia-DX-convention-tp7500313p7501258.html
Al,
Great information! Yes, I can agree that properly tightened UHF
connectors do not inflict much loss. I think the main problem has been
with inadequate tightening - as you pointed out the shield connection
requires that that UHF connectors be tight. How many hams wiggle the
PL-259 connector a bit to be certain it is seated in the notch of the
SO-239 - this is not a casual connector for making quick connections and
disconnections.
Where am I going with this - well, with the KPA100, we have long
recommended "disconnect the antenna when not in use" to protect the
wattmeter diodes from static damage. While this is a good concept, the
literal interpretation of that statement may actually inflict damage
because of the way the UHF connector "connects". With a PL-259, the
center conductor is what makes contact first - if there is a static
charge on that feedline, that charge will be transferred to your
equipment without a chance to bleed it off - the only way to prevent
that is to either short across the feedline (if there is a ground
connection for the shield) or some other means should be used to bleed
off the charge before attaching a feedline with a PL-259 connector to
any equipment. Type N and BNC do not have this problem - the shell
makes contact first.
On 4/25/2012 7:09 PM, Alan Bloom wrote:
> (Changing to a more descriptive Subject line)
>
>
> 4. Regarding RF loss in UHF connectors, it isn't as bad as many people
> think. I did an Internet search and found the Usenet posting I made on
> the subject about 20 (!) years ago:
>
>
______________________________________________________________
Elecraft mailing list
Home:
http://mailman.qth.net/mailman/listinfo/elecraftHelp:
http://mailman.qth.net/mmfaq.htmPost: mailto:
[hidden email]
This list hosted by:
http://www.qsl.netPlease help support this email list:
http://www.qsl.net/donate.html