RFI
[Top] [All Lists]

[RFI] Low Power 10M RFI!

To: <rfi@contesting.com>
Subject: [RFI] Low Power 10M RFI!
From: w1rfi@arrl.org (Hare,Ed, W1RFI)
Date: Mon, 17 Dec 2001 13:34:14 -0500
The first thing that may help is the text of the "RFI neighbor pamphlet." 

See http://www.arrl.org/news/rfi/neighbors.html.

If the problem is on 10 meters, you may need to filter the phone line with a
K-com or Radio Shack telephone-interference filter right at the phone AND
use a K-Com filter for the handset cord.  If the phone has any connection to
the ac mains, usually through a "wall cube" type power supply, an F-140-43
ferrite core and about 10 turns of wire on the power lead, right at the
phone, may be needed.

Don't discount the possibility that one phone device may be rectifying the
RF and then the resultant audio is getting into the whole system.  Simplify
the problem to one phone, to see if the line is clear, then start adding
devices back one at a time.

See     http://www.arrl.org/tis/info/rfitel.html
        http://www.fcc.gov/cib/consumerfacts/interference.html

73, 
Ed Hare, W1RFI
ARRL Lab
225 Main St
Newington, CT 06111
Tel: 860-594-0318
Internet: w1rfi@arrl.org
Web: http://www.arrl.org/tis



> -----Original Message-----
> From: Jon Ogden [mailto:na9d@speakeasy.net]
> Sent: Monday, December 17, 2001 12:50 AM
> To: rfi@contesting.com
> Subject: [RFI] Low Power 10M RFI!
> 
> 
> UGH!
> 
> Got a knock on the door this afternoon from my lovely neighbor while
> operating the ARRL 10M contest.  He told me that I was 
> getting into his
> phone.  Not only that, he claimed that I was getting into the 
> neighbor on
> the other side of him, the neighbor beyond that and the 
> neighbor across the
> street from him.  He claimed, they were talking about taking 
> "legal" action
> (but not him).  He said the neighbor across the street had to 
> turn of all
> his TVs and radios because I was getting into everything.
> 
> Interesting..... I ran about 150 Watts all weekend.  And if 
> you've been to
> my neighborhood, you know how big the lots are and how far these other
> people are away (they're at least 75 feet away if not farther 
> our lots are
> all at least 50 feet wide).  And the funny part was, after my 
> conversation
> with him, I looked over at the neighbor across the street 
> from him and could
> see that he was watching the Green Bay/Tenessee game during 
> the last 2 hours
> of the contest (big TV)!  So I wonder if he REALLY talked to 
> them or if I
> was interfering cause I kept checking to see if I could see 
> the TV on in
> that other house.
> 
> He came over here demanding that I fix the problem on my end. 
>  I told him
> that I seriously doubted it was on my end and the problem was 
> with his phone
> and that he'd need to get a filter from Radio Shack for it.  
> I also told him
> that legally, I am in the clear and that I am licensed to do 
> such activity.
> He continued to claim that it wasn't his problem to fix, yet 
> he said he
> wanted to work with me for a solution.  I said, "OK, so you 
> are saying you
> want to work with me, but you don't like the solution that I 
> give you that
> IS the solution.  So I can't help you...."  He finally calmed down and
> became more reasonable and said he'd get the filters for his phone.
> 
> Now, I haven't had a problem with this guy for over 2 years.  
> And during
> that time, I've operated probably 5 to 10 contests and most 
> of them at full
> legal limit.  So I was shocked that when running 150 Watts, I 
> had a problem.
> 
> Now, I know that I was running my audio and compressor pretty 
> hot.  In fact,
> I may have been slightly overmodulating a bit.  Now, while 
> that might create
> splatter on the ham band, I don't understand how that could 
> cause RFI to
> other people near by.  It was also kind of rainy and damp 
> here today.  Could
> that have anything to do with it?
> 
> I am stumped.  If I really did bother all these neighbors, 
> it's a first.  My
> antenna SWR is just fine.  I was running only 150 Watts, but perhaps a
> little over modulated and it was damp?
> 
> Is this a recipe for RFI???????  Any ideas?
> 
> 73,
> 
> Jon
> NA9D
> 
> -------------------------------------
> Jon Ogden
> NA9D (ex: KE9NA)
> 
> Member:  ARRL, AMSAT, DXCC, NRA
> 
> http://www.qsl.net/ke9na
> 
> "A life lived in fear is a life half lived."
> 
> _______________________________________________
> RFI mailing list
> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
> 

<Prev in Thread] Current Thread [Next in Thread>