[Elecraft] 12 meter K3 RFI from nearby FM station

James Bennett w6jhb at me.com
Thu Feb 11 15:27:42 EST 2016


And if a second receiver is not available, perhaps hook the K3 up to a battery and transport it to another location, as far away as possible from your QTH.

Jim Bennett / W6JHB
Folsom, CA

> On Feb 11, 2016, at 11:44 AM, Bob McGraw K4TAX <rmcgraw at blomand.net> wrote:
> 
> One other item, if available, try another brand/model radio using the same power supply, location, antenna and such.   If it is present on that radio, most likely it is radiated.  If it is not present, then most likely it is generated in the K3.  {To which that is an entirely different can of worms.}
> 
> 73
> Bob, K4TAX
> 
> 
> 
>> On 2/11/2016 12:55 PM, Jon Zaimes wrote:
>> Yes, that is the case. Hearing it on both of my K3 transceivers with only
>> the 12v power cable connected, nothing else (listening on speaker).
>> 
>> Thanks to all for the tips. Still absorbing the advice before proceeding.
>> 
>> 73/Jon AA1K
>> Felton, Delaware
>> www.aa1k.us
>> 
>> -----Original Message-----
>> From: Elecraft [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Alan
>> Sent: Thursday, February 11, 2016 12:04 PM
>> To: elecraft at mailman.qth.net
>> Subject: Re: [Elecraft] 12 meter K3 RFI from nearby FM station
>> 
>>> On 02/10/2016 03:57 PM, Jim Brown wrote:
>>> Yes, this hit me between the eyes as well. The K3 has Pin One Problems
>>> at many (most?) connectors, so RF current flowing on shields of cables
>>> plugged into those connectors will couple into the K3. I've been
>>> preaching to Wayne about Pin One Problems since 2004, when we met in
>>> Dayton.
>>> 
>>> If the problem is around 90 MHz, I'd use multiple one-turn and two
>>> turn chokes with #43 material on every cable except the SO239 output,
>>> which IS actually bonded to the chassis. Also choke the power cable.
>> But it sounds like he was still getting the problem with no cables connected
>> to the K3:
>> 
>> On 02/10/2016 06:58 AM, Jon Zaimes wrote:
>> ...
>>  > Even when ALL cables are removed (only the power lead connected).
>>  > Grounding or ungrounding made no change. I tried the radios on a  >
>> battery but still had the RFI. Tried some ferrites on the power  > lead but
>> no change.
>> 
>> I suppose it could be a "pin 1" problem on the power leads.  It's kind of
>> hard to avoid that with an Anderson PowerPole connector.  Probably
>> additional low-pass filtering on the DC input would help.
>> 
>> Alan N1AL
>> 
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Elecraft at mailman.qth.net
>> 
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html Message
>> delivered to jz73 at verizon.net
>> 
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Elecraft at mailman.qth.net
>> 
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to rmcgraw at blomand.net
> 
> 
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to w6jhb at me.com


More information about the Elecraft mailing list