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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