[Elecraft] Hum Coupling

[Fraser Robertson]

Interesting - I had complaint on air recently of having a wide CW carrier 
when using a tube linear about two feet from the K2/100.

Fraser G4BJM


>From: Earl W Cunningham <k6se at juno.com>
>To: jwiley at alaska.net, mike.harris at horizon.co.fk,Elecraft at mailman.qth.net
>Subject: Re: [Elecraft] Hum Coupling
>Date: Mon, 1 Nov 2004 19:49:07 -0800
>
>Jim, KL7CC wrote:
>
>"So, maybe the problem [hum getting into the K2's PLL] could be worth
>another look, as in maybe there is  another way to solve it?  Could
>something be done to the K2 itself to make it immune to this problem?"
>==========
>Hum coupling from the K2's power supply xfmr is not much of a problem
>because separation of a couple of feet eliminates it.
>
>Hum coupling from a linear amp's hypersil HV xfmr is another story,
>however.  Six feet is not sufficient distance from my Alpha 76CA.  Ditto
>when my K2 was tried more than six feet from my friend's Alpha 99.
>Thirty feet separation does clear up the problem, but that is
>unacceptable.
>
>I am a QRO operator who chases DX and works the contests, so I cannot use
>my K2 for this purpose because of the trashy signal it puts out when used
>with an amplifier.
>
>Elecraft is aware of the problem and was going to investigate further
>into it, but that was perhaps a year ago.  They were going to look into
>the possibility of fabricating a mu metal shield, but I have heard
>nothing back from them since.  If no fix becomes evident soon, I'm afraid
>my K2/100 will be up for sale.
>
>73, de Earl, K6SE
>_______________________________________________
>Elecraft mailing list
>Post to: Elecraft at mailman.qth.net
>You must be a subscriber to post to the list.
>Subscriber Info (Addr. Change, sub, unsub etc.): 
>http://mailman.qth.net/mailman/listinfo/elecraft
>Help: http://mailman.qth.net/subscribers.htm
>Elecraft web page: http://www.elecraft.com

_________________________________________________________________
Stay in touch with absent friends - get MSN Messenger 
http://www.msn.co.uk/messenger