[NLRS] 6m and up noise

[KB0DCO, Thomas]

Hello,

               Just got a chance to catch up on my emails....  NØTWP 
Bill, and I Thomas KBØDCO, went out with our DFing stuff a long time ago 
around 1991 - 1993 or so. Bill used to live in an apartment complex on 
Cleveland Ave. (the one closest to 35W on the 3rd floor).... if I 
remember right, north of Hwy. 36 and south of 694.

                Bill used to do work stations on OSCAR 13. When he 
pointed his KLM antennas towards the Shoreview towers.... he was getting 
that arcing noise back then too. He took his Yaesu FT-736R and my 4 
element beam with attenuater in my car. As we were hunting the noise 
out, as we got closer to the base of the tower (the single one not the 
double ones.) And the signal disappeared! We went south from the tower 
on the road just north of 694. The signal came back. I had the beam set 
up for vertical polarization the signal was week pointing back at the tower.

                Then I had Bill point the beam up towards the top of the 
tower. Signal came up. I told him we should try tuning the beam to a 
horizontal polarization. THEN the signal came way up! Eyeballing from 
back of the beam..... it seemed to be around the second red light down 
from the top.

                Bill talked to the engineer there, but I don't remember 
what happened after that. Far as I know it went away after awhile. I no 
longer live in the area, so not sure if "this noise" is still happening 
or not. One more thing to add.... When it was very windy.... that's when 
it made the most noise.

                Just thought to post this..... It seems to me that the 
issue never really went away.

P.S. After moving into Mcleod Co., I heard the same type of noise out 
here. It brought me back to this story and hope it was not coming from 
the same source. Possibly another radio tower in the area. Lucky for 
me.... I have not heard the same type of noise since about 1996. Hope 
they get that problem fixed.

73
Thomas
KBØDCO

 
Chris Elmquist wrote:

>
>On Tuesday (02/28/2006 at 07:31PM -0600), John Oehlenschlager wrote:
>
>>>From "UP NORTH" in EN26oo I see a very strong noise increase when pointed 
>>directly at the Twin Cities.  On 6M the noise is typically 2 S-units above 
>>the ambient when pointed other directions.  On 2M it is about an S-unit 
>>higher.  Don't seem to see any significant noise on 222 or 432.  So much 
>>for a quiet spectrum!   K0JO 
>>
>
>One noise issue we have battled for years is at the Shoreview towers
>and has to do with the elevator cables arcing between each other and
>the tower structure when they blow in the wind.
>
>This not a continuous noise floor increase but instead a crackling,
>periodic noise burst like you would expect from an arc.  When the wind
>is up around Shoreview, I can get S9 to 10 or 20 dB over S9 noise bursts
>on 2m from this situation.  The noise blanker in my FT736 will knock it
>down somewhat but not completely.
>
>The cables arc because they are so hot with RF where they run past the FM
>broadcast antennas part way down from the top of the tower.  It became
>more of a problem when the tower owners stopped parking the elevator
>some distance up the tower and instead now keep it on the ground... as
>I understand it.
>
>I once discussed the issue with the engineer in charge at KMSP, which
>owns the tower, and he said they would investigate if we were able to
>produce spectragrams of the noise in action.  I don't think anything
>has been done past that point.
>
>I also don't think they are licensed for spark gap transmitter operation
>with a 1500' vertical antenna... in any case.
>
>I am not sure if this is the noise you are hearing.  I know there are
>other issues with the TV channel 2 transmitter that goes back years
>to when they upgraded to a Harris transmitter from whatever they used
>to have.  I know some folks here in the Cities worked that issue pretty
>hard when the transmitter went online but I think it ended when someone
>ruled that it was in compliance and the hams were too "sensitive".
>
>Chris N0JCF
>