[Elecraft] K1 #1534 nears it's first birthday

[Dale Boresz]

Hello Martin,

I've experienced the same thing, only in my case the computer was in a 
room on the top floor of the house, and about 5 meters below the 
elements of a Hex Beam which was mounted on the roof of the house. I 
experimented quite a bit, and ultimately found that replacing the 
computer's case with a high-quality computer case completely solved the 
problem. A good computer cabinet will employ special techniques to 
assure that all surfaces are electrically connected together so that the 
cabinet can act as an effective shield. It's likely that the source of 
the noise is not just the power supply, but also the compter motherboard 
which is routing square waves all over the place.

The brand which I happened to use is called "Enlight". If you search the 
internet for "Enlight computer case" you'll probably turn up quite a few 
matches. I don't recall the exact model number but after doing a quick 
search myself on the internet, it was very similar to, if not exactly, 
the model EN-7250 mid tower as seen at the following URL:
http://tomshardware.bizrate.com/buy/products__att259--43528-,cat_id--466,rf--tom020.html
(look at the second case shown)  I bought mine from a local computer 
parts store, but many places stock Enlight cases. I have four computers 
in my house, two of which are in the shack about 6 feet from my K2, and 
all are in Enlight cases. I don't have any interference from any of them.

All the usual disclaimers apply, about not being associated with Enlight 
etc.  I'm just a satisfied customer, but there are undoubtedly other 
brands which work just as well.

Best of luck in resolving the interference problem.

73, Dale / WA8SRA


>.... My son's pc is located a few feet
>above the rig in the upstairs bedroom and makes a lot of hash on most bands
>including the MW broadcast band. The qrm is from the pc power supply since
>turning off the monitor makes no difference. When I remove the antenna the
>qrm disappears so I guess it isn't mains borne. The ant is a coax fed
>dipole with no balun and no connection to earth. Any ideas would be
>welcome.
>
>  
>