Eureka... This afternoon , I was in my backyard poking around with a VHF
dipole made from an old set of rabbit ears with a balun at the feed point ,
and my next door neighbor stuck his head over the fence and asked if I was
looking for noise
again!!!
I told him , yep, and I had a notion it might be some of his battery
chargers... Well we went in his garage with my 6.5 to 8 mhz loop and R10 rx,
and the signal was pretty strong but the null kept pointing inside the house
..I asked if he had a computer just inside the house wall and no , they
(three of em ) were at far end of house... so we started to the other end of
the yard and the signal pegged the R10 at about 6890khz , added the 20 db
atten in the R10 and still pegged at his front door ..I took off tne tuned
loop and put on the little whip that comes with the R10 and it was just
audible with 20 db atten and fairly strong with no atten, and I asked him to
take the rx inside and poke around for strongest signal.
To make an already long story shorter , it turned out to be a blasted touch
lamp on the other side of the front wall . He unplugged it and the noise is
essentially gone on 40 meters. Still have some other extraneous stuff to
hunt down but none are nearly as strong as this was, and what is left is
pretty narrowband birdies at spot freqs like horizontal oscillators . Some
stuff at at 60 khz rep but its pretty weak and I could live with that.
I can actually hear signals on 40 meters again that are under S9 !!! He
mentioned that the light had been acting up and turning itself off and on
randomly ( I suspect that could have been me !) so I hinted that maybe the
lamp was going bad. About that time his wife showed up and said she had told
him to unplug that lamp a month ago !!!!
So another touch lamp story !!!!!
Rgds... Hank
----- Original Message -----
From: "HENRY PFIZENMAYER" <pfizenmayer@worldnet.att.net>
To: "RFI List" <rfi@contesting.com>
Sent: Wednesday, November 10, 2004 7:48 PM
Subject: Re: [RFI] 6.5 to 7.5 mhz birdies (LONG)
> I wonder if any of the gurus on this forum have run into my problem. About
> two months ago I started getting very rough birdies about every 132 - 136
> khz from around 6 mhz to 8 mhz with worst between about 6.5 and 7.5 mhz.
> With the BFO on (cw reception) you hear the very rough birdies , but
> between the birdies is almost like white noise that just keeps the S meter
> around S7. When you listen to this as AM , it sounds like 60 hz rep rate
> line noise at the birdies fading down to white noise then back again at
next
> birdie.
>
> So far I found birdies from street lights a block away , APS cane out with
> their sniffers and agreed they were bad , and replaced the heads and they
> now seem quiet.(Using an ICOM R10 and tuned shielded loop antenna).
>
> A couple nights ago I walked the neighborhood streets with the loop and
> found what I felt was a source about 400 feet away , as I walked by the
> house , the loop null kept nulling on the house , and at the house I could
> put in another 20 db atten and it was still strong. I didn't think it was
a
> good idea to prowl the alleys behind the house after dark , so went down
the
> alley the next morning and found the power pole closest to the identified
> house just boiling with birdies and hash from 6 to 8 mhz. There was a
telco
> "pedestal" box there that had been bashed and the cover left off and the
> whole mess just covered with black plastic ! I walked around to other
> pedestals in the area and the ones with shields still intact were MUCH
> quieter , but all had birdies . The birdies seemed to be loudest at
somewhat
> different frequencies at different pedestals , and in fact at one , it
> shifted form about 6800 khz to 6600 khz while I was standing there. In
many
> but not all case , the worst noises were at locations that fed two
seperate
> lines into a house.
>
> I got Qwest to come out this morning and the blasted thing was quiet ..
but
> he did clean up the mess at the one pole and removed gobs of extraneous
> stuff that had been left hanging over the years. AND all the other
> pedestals were dead quiet .
> So something was certainly different from day to day . The telco guy was
> super co-operative , but he admitted he had no idea what I was hearing so
he
> got me the name and phone number of a guy who was an engineer in my Cactus
> Central Office Area. He was the guru for VDSL , and in our conversation ,
he
> first of all said their VDSL stuff started about 1.5 mhz and was pretty
well
> gone by 6 mhz. He said what I was describing did not sound like VDSL , but
> he did say that if I was hearing birdies that loud , it may have messed up
> some VDSL customers. He was going to check the area for VDSL customers and
> complaints and get back to me and also to talk to some other engineers to
> see what they thought.
>
> I asked if they had started any DSL or other service in my area about two
> months ago and he said not. He said the next time it popped up , to give
him
> a call and he would bring out a spectrum analyzer and look at what I was
> finding.
>
> Now it could be that somebody has some sort of alien gear hooked to the
> phone lines that is inserting this noise on the line I dunno, but it
> certainly was on the phone lines for several days while I was poking
around.
>
> I do know that something around my area has a heck of a signal at about 55
> khz S9 on an 80 meter dipole and a R7 receiver.
> But the birdies are not repeating at 55 khz. I am gonna make me a 55 khz
> loopstick to see where that is if I can.
>
> Anybody have any ideas what this stuff is ? It makes it almost impossible
to
> copy anything under S7-S8 on 40 meters. Strangely , 80 meters is not
nearly
> as bad , and 160 reasonably clean so it makes me think its probably not a
> switching supply .
>
> Sorry to be so long but needed to try to set the scene . I could make a
wave
> file but only have dial up so hate to mess with big files.
>
> Rgds... Hank K7HP
>
>
>
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