My Weirdest RFI Problem

A case of PEBKAC (Problem Exists Between Keyboard and Chair)? Tell us about your war stories!
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Dale H. Cook
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My Weirdest RFI Problem

Post by Dale H. Cook » Wed May 16, 2012 10:08 am

Most of us have battled RFI problems. Some of those are rather pedestrian (AM RFI on a POTS line near the transmitter), but some can get rather bizarre. I'll kick things off with a case of mine from about 1980.

We had just gotten WPOE, Greenfield, MA, on the air. It was a two-tower 10 kw daytimer on 1520, and was my first CE position. Shortly after we hit the air I got a call from a homeowner across the street from the transmitter site, smack in the middle of the main lobe, complaining about hearing the station in his basement. It turned out that his water meter was at one end of the basement, and the copper line coming in from the meter ran the entire length of the back wall to the other end where the water heater and all the distribution lines were located. I could hear that long copper line singing. A look at the fittings in the line showed a bit of corrosion at one, and bridging across that fitting stifled the singing. I got out my propane torch, flux, solid plumber's solder and a plumber's brush, shut off the water to the house, and proceeded to disassemble and re-sweat that fitting. That cured the problem - the only RFI case that I have ever cured with my skills as a shade-tree plumber.
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Deep Thought
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Re: My Weirdest RFI Problem

Post by Deep Thought » Wed May 16, 2012 10:13 am

LOL...that's funny. Probably saved the neighbor an inevitable wet basement too. :mrgreen:

I've been involved in quieting singing suspended ceilings but no singing plumbing...except at the transmitter site itself. :shock: 8)
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Re: My Weirdest RFI Problem

Post by ChuckG » Thu May 17, 2012 9:50 pm

I had a pretty good chuckle when a group of psychiatrists, who built a new clinic less than 100 feet from WAGN, Menominee MI's AM tower stopped in one day to announce that they were "hearing voices". :lol:
I suggested that was their specialty, not mine. They saw no humor in it, lol. A couple Sandman telco filters fixed it up.
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Re: My Weirdest RFI Problem

Post by rockmanac » Thu May 17, 2012 10:31 pm

ChuckG wrote:I had a pretty good chuckle when a group of psychiatrists, who built a new clinic less than 100 feet from WAGN, Menominee MI's AM tower stopped in one day to announce that they were "hearing voices". :lol:
I suggested that was their specialty, not mine. They saw no humor in it, lol. A couple Sandman telco filters fixed it up.
LOL
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Re: My Weirdest RFI Problem

Post by awsherrill » Fri May 18, 2012 10:02 am

I got a call from Mother Superior at the local convent one day. The convent had a huge custom-built organ, and the amp was doing a fairly good job of receiving our CHR-FM, which was on a nearby tower farm. Nothing like hearing Madonna during services to put nuns in a foul mood.

I don't remember doing anything specific to fix the problem. Since the organ was a custom job, the best I could do was give advice to the guy who installed it. Either the problem went away by itself or he fixed it. Funny thing, there were four or five class-C FMs (including ours) all located at this tower farm, but ours was the one that got into everybody's electronics. Must have been that low-gain antenna we were using.

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Re: My Weirdest RFI Problem

Post by K9EZ » Tue May 22, 2012 10:45 am

ChuckG wrote:I had a pretty good chuckle when a group of psychiatrists, who built a new clinic less than 100 feet from WAGN, Menominee MI's AM tower stopped in one day to announce that they were "hearing voices". :lol:
I suggested that was their specialty, not mine. They saw no humor in it, lol. A couple Sandman telco filters fixed it up.

Ahhh good ole W'AGN! Love that tower in the back. Do they still have a funnel as a feed through insulator? How did they ever have a ground plane?
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Re: My Weirdest RFI Problem

Post by BroadcastDoc » Tue May 22, 2012 2:15 pm

No sure about the tower, but they're still running the old Gates transmitter!
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Re: My Weirdest RFI Problem

Post by RGORJANCE » Tue May 22, 2012 2:56 pm

WAGN-AM

Da Fossil is having a senior moment. Can't remember which AM it was, but I was involved in the installation of a Motorola Canopy Wireless Internet xmttr on one of the AM sticks up there. Had an interesting time. Retuned the ATU and actually improved their VSWR from the "before" readings. I think that one was using a Gates One, or an SX.

Does WAGN use one of them more modern rigs, or is it like a BC-1T or BC-1G???

Fossil

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Re: My Weirdest RFI Problem

Post by BroadcastDoc » Wed May 23, 2012 8:36 am

They're using a BC-1G I believe. The SX may be at WMAM which is right on the river.
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Re: My Weirdest RFI Problem

Post by RGORJANCE » Wed May 23, 2012 10:49 am

WMAM is where we put the canopy. Don't recall ever going to the wagon site.

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Re: My Weirdest RFI Problem

Post by BroadcastDoc » Wed May 23, 2012 11:14 am

WMAM is an interesting one. It's a very thin tower - constructed out of pipe or something like that.
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Re: My Weirdest RFI Problem

Post by NECRAT » Wed May 23, 2012 1:13 pm

BroadcastDoc wrote:WMAM is an interesting one. It's a very thin tower - constructed out of pipe or something like that.
Is it a Lingo tower, by chance?

Similar to this http://www.necrat.us/730chicopee.html
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Re: My Weirdest RFI Problem

Post by w9wi » Wed May 23, 2012 2:45 pm

Having pulled this totally off-topic :? , why is there a batwing on the WACE tower?
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Re: PIPE TOWER

Post by RGORJANCE » Wed May 23, 2012 3:07 pm

I think there were three pipe towers in Wisconsin. I seem to recall these locations. The only one I might be wrong about would be Richland Center. WRCO-Richland Center, WMAM-Marinette, WI, WOMT-Manitowoc, WI. To the best of my knowledge, they are all replaced with conventional towers.

Fossil

PS-A bit of trivia. I found out one evening at the best local eating joint in Richland Center that it WAS A DRY COUNTY!!!!! I COULDN'T EVEN GET 3.2 BEER! How uncivilized can a place be?

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Re: My Weirdest RFI Problem

Post by NECRAT » Wed May 23, 2012 4:38 pm

WUTI , the former WRUN in Utica NY has five "pole towers" inline in a straight array.

And Doug, the Batwing was for a former FM which has long since been off the air.
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