[RFI] RF

[Edward Mccann]

Jim-

Was the update to the 168 page power point entitled "Coaxial Transmitting Chokes"

Or to: 

"A Ham's Guide...."
Version 5a, 5 June 2010

Or:

Something else?

Thanks,
73
Ed McCann
AG6CX




Sent from my iPhone

> On Dec 23, 2016, at 2:33 PM, Jim Brown <jim at audiosystemsgroup.com> wrote:
> 
> Bill and Bob,
> 
> While this is certainly worth trying, I suspect that the problem is caused by the antenna itself being so close to the victim devices. And I would definitely wind serious chokes onto wiring connected to that garage door unit. By serious, I mean at least 12 turns around a #31 toroid, or half as many through a clamp-on that's an inch long.
> 
> Since this antenna is inside, I suspect that you're running barefoot. If so, or if you're running less than about 300W, the bifilar-wound choke using a pair of #12 or #14 THHN on a single #31 core would handle the power unless the antenna is VERY badly unbalanced.
> 
> BTW -- about six months ago, I updated RFI-Ham.pdf to address power handling of bifilar wound chokes on #31 toroids. If you are considering using one, by all means download it again.
> 
> 73, Jim K9YC
> 
> 73, Jim K9YC
> 
>> On Fri,12/23/2016 1:41 PM, Robert Nobis wrote:
>> Bill,
>> 
>> I had a similar problem with an electronically operated doggy door.  What I found was that I had relatively high common mode current on my antenna feed so the feed was also radiating. My antenna was not perfectly balanced as one end was close to metal siding. I added an antenna feed line choke following the recommendations from Jim Brown’s tutorial (k9yc.com/RFI-Ham.pdf <http://k9yc.com/RFI-Ham.pdf> ), and the doggy door problem disappeared.  I used 6 turns of RG8 through five 2.4” o.d. #31 toroidal cores for 80-meters.
>> 
>> 73,
>> 
>> Bob Nobis
>> n7rjn at nobis.net
>> 
>> 
>>> On Dec 23, 2016, at 10:59, Bill Price <billp7634 at sbcglobal.net> wrote:
>>> 
>>> 
>>> I live in a HOA subdivision with restrictive covenants. As such, at this time all my antennas are in my attic. I just strung a fan dipole up for 75 and 17. When I operate on 75 I have RF issues. Two of my security lights come on, one of the garage door opener lights come and an electric soap dispenser (motion activated) comes on and dispenses a butt load of soap. I thought it may be due to one side of the 75M dipole coming close to a length of romex. So I located that romex and put two snap on ferrites around that wire with the romex wrapping twice through the ferrite. I also put a ferrite on the power wire from the wall wart after having wrapped that several times. The problem still exists. I also have a 40M dipole and a 10M beam in the attic and have no problems with running a KW at any frequency other than 75M. The ferrites I have are a 31 mix. Any ideas as to how to solve this issue?
>>> 
>>> Bill   W5LO
>>> _______________________________________________
>>> RFI mailing list
>>> RFI at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/rfi
>> _______________________________________________
>> RFI mailing list
>> RFI at contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
> 
> 
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi