[RFI] [Fwd: Noise Follow up]

w4lde w4lde at numail.org
Mon Sep 15 21:17:23 EDT 2008

Original post by Ron W4LDE

>>>If this question is inappropriate for the reflector I apologize but as 
of last Friday 9-5-08 I started to experience significant noise (S-9) on all 
bands from 160 through 15M with the lower frequencies much stronger.  I 
thought that it was due to power line noise but it appears to be 
intermittent in that it completely disappeared last Friday evening but 
once again showed up last Saturday and stayed this way.  On the Ft1000mp 
the noise blankers are completely ineffective.  At the same time I 
started having internet problems and the cable company indicated they 
should have the speed issue fixed by Tuesday.<<<

>>>The cables are run on poles until they enter a subdivision which then 
run underground.  My question is can cable lines be the possible problem 
to HF frequencies?  The power and cable companies have been installing 
new poles and running new lines in the area which initially led me to 
believe it was a power issue however, while I was writing this email the 
noise completely disappeared for a few seconds and then reappeared.  As 
I was looking out my window I noticed a cable company buck truck  
through the woods towards the main road, I am off now to talk to them 
and see what I can discover.  Any suggestions?<<<

----------Follow up !!! -------------------- 9-15-08 ------------------

On 9-8 I contacted the local power company via email regarding the above, unexpectedly 
I received a call from the Maintenance Manager who stated don't worry we will be out 
maybe tomorrow and find the cause.  They did show up, two buck trucks and full crews plus a 332-335 MHz Yagi and noise receiver.

Unfortunately they said that they couldn't find anything and suggested it might be from a neighbors home.  
They scanned my home but couldn't find a thing.

I was one unhappy ham and expressed that they needed to keep looking.

I believe I have ruled out a radio problem since the noise was about the same on a FT-1000mp and a FT-847 and neither 
noise blanker would dent the noise.  A MFJ-Noise phasing unit helped some but only improved the noise by about 1-2 S-units.

I spent some time connecting and disconnecting home devices plus disconnecting one house breaker at a time. 

Friday the 12th I decided that maybe I could help find the problem and using a 
Yaesu VX-5R and rubber ducky at 134MHz and also at 329MHz AM started my search.

I found significant noise at three different power poles, all new ones, with two west of my antenna about 1/8 mile and the other
to the east at also about 1/8 mile.  So I thought I had found the problem and would be reporting this condition today.

When I came into the shack this AM to compose the email I happen to turn on the rig and to my amazement the noise was gone.
eleven days I had a Ham Radio Black out on the low bands.  Was I one happy guy.  I thought I better go check out the poles.
Off I went and yes the noise was gone at the poles, very quite.

Went out later this afternoon and took the VX-5R, things were still quite up and down the main road.
After being gone for three hours as I was approaching the sub-division I turned the 
VX-5R back on and WAM there was the same power poles and noise.  My heart sunk, O-Sh_t I shouted and my XYL 
who understood the situation gave me her famous look and said keep on looking, write the reflector they can help.

Well after arriving home and one hour later in the shack I turned on the radio and found NO significant noise. 
S-0 on 20-meters, S-2-3 on 30 meters and maybe as high as S-4 on 40M, at 4PM thats not bad.
I was amazed once again and kinda dumb founded as to were to look next if I have to.

Here's some of my thoughts,

1.  Today for the first time in the past few weeks we finally had a cool day, high around 80 (occurred around 5PM)
and a low tonight of 60
	a) Lower temps caused all connections to tighten and when it finally warmed up around 4-5pm it started again at the poles.

2.  Since there is still home building going on near us as the crews were leaving the construction site a week ago 
maybe they left chargers on for there power equipment and after doing there thing finally turned them off this AM and left the site.

3.  I did find out that the telephone company was having lots of noise problems 
from there own installation.  Not at my home but close.
	a) Can't believe thats the fix since the noise stopped early on Monday 
which didn't give them much time to complete the task, they started last Wednesday.

4.  Cool days, less power consumed by the A/C units, less amps, less noise (is it s stretch?)

Ok I thought, maybe I should invest in a 144/440 hand held Yagi plus the cables and adapters to help in a wider search 
area but wanted recommendations as to what I should be looking at if the noise returns I would be using the VX-5r on 138 am MHz and 332 am MHz.  
Any thoughts are appreciated.

I believe I have ruled out a radio problem since the noise was about the same on a FT-1000mp and a FT-847 and neither 
noise blanker would dent the noise.  A MFJ-Noise phasing unit helped some but only improved the noise by about 1-2 S-units. 

Any ideas where I should look next time and heres a pray that there isn't one, is it worth the cost to invest now or wait?
get a 114/440 Yagi or just stay with a 144 hand held Yagi. 

Thanks for the bandwidth and thoughts, wish I could take credit for the current fix but I'm happy right now!

73 de 

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