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PostPosted: Wed Dec 23, 2015 3:03 pm 
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Joined: Thu Jul 09, 2015 7:39 am
Posts: 4
I am somewhat new to all of this so I am looking for some input for an issue I am having. Its the age old static issue. I listen to ICOM Police and Fire from the south end of Whidbey Island and I am having a difficult time receiving the Oak Harbor Fire and Police frequencies clearly. The frequencies will come in somewhat clear for several hours or less each day, then start to deteriorate( a lot of static so you miss every other word) for the remainder of the day. This is a daily occurrence, and it does not follow any pattern. I am wondering if I am too far away, bad antenna placement, CME's? What are my options?

Does anyone else have this issue who listens to ICOM? The rest of the frequencies come in fine.

I am using the following: Uniden BCT15X, 10' of RG142 Coaxial cable, DBJ-1 Dual Band antenna (152-157 MHz and 460-470 MHz) Ed Fong. The antenna is on the NW side of my house about 30 feet up on the peak. The scanner is just below the antenna on the second floor of my house. I am roughly about 30 miles from the ICOM dispatch building.

Oak Harbor police freq 460.575 PL 100Hz
Oak Harbor Fire 154.430 PL 100Hz


Any thoughts?

Thanks again.


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PostPosted: Wed Dec 23, 2015 6:32 pm 
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Joined: Wed Mar 10, 2004 2:32 pm
Posts: 139
Location: FB2 Simulcast
Your former synopsis is correct. Distance and topography play a major role for FM signal performance.

Weather conditions and humidity can also influence signal performance as well. Of course as you increase in the frequency band, cable loss and coax connector types each contribute to feed line loss.

Both of those VHF Fire and the UHF P.D. frequencies licensed to the city, but they are currently limited in signal performance. Remember that public safety frequencies are federally licensed with the understanding that they are to be shared / coordinated with other users, and that includes Canada as well.

Both of these freqs are currently licensed to the city with limited RF output power for obvious reasons. They have no specific need to send their signal(s) way beyond their service area.

The vintage MTR2000 VHF ( FIRE 6 ) transmitter is the sole ( simplex ) machine operating on that frequency within Is Co. Simplex means that it is configured for unit-to-unit operation, thereby somewhat limiting the signal penetration from that berg. It is programmed at 24 watts output and the antenna mast has an elevation of 40 feet on the I-COM 911 tower. The I-COM 911 elevation is positioned at about 20 AMSL.

Although some similar signal design limitation ( elevation ) factors are also employed with the UHF OHPD freq, it is instead configured as a low output FB2 ( repeater ).

You could perhaps experiment with a directional yagi antenna, but even so, the distance is more likely the main factor here.


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PostPosted: Wed Dec 23, 2015 6:37 pm 
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Joined: Mon Jan 03, 2005 1:17 am
Posts: 2591
Location: Not Gulfport
Presuming your coax and antenna connections are all securely wrapped *AND* the fact that you're receiving them well at times, suggests it's not a hardware issue. It could be related to ionospheric conditions but those affect HF primarily.

The cheapest solution I can think of would be:

1. Check your antenna connections and hardware no cracks in insulation, no water inside PVC antenna, etc.)
2. Make a trip to HD or Lowes and buy a 10ft piece of EMT conduit -- about $10 for a 1.25" piece
3. Mount the DBJ-1 onto the EMT conduit

Another idea/suggestion would be to buy a cheap AM SW portable radio (Tecsun PL-380 is roughly $43 and sweep your house and neighborhood for any obvious RFI that could be causing interference. Powerline interference is notorious for causing issues. But in this digital age, there's plasma TVs, Broadband over powerline and a ton of other RFI garbage. Search in AM mode on say 7mhz, 11mhz, 15mhz and 28mhz, (When you hear RFI you won't mistake it for anything else. It's usually quite obvious.)


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PostPosted: Wed Dec 23, 2015 9:10 pm 
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Joined: Thu Jul 09, 2015 7:39 am
Posts: 4
I appreciate the feed back and very informative information. I was leaning towards two factors, distance and likely weather. I was thinking about raising my antenna up another 10 feet to see if that helped. Maybe after the holidays I will spend some time on this and see what I come up with.

Thanks again for everyone's help.


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PostPosted: Sat Dec 26, 2015 9:07 am 
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Joined: Tue Mar 02, 2004 12:26 pm
Posts: 830
I'd lean towards the man-made interference if it's varying during the day, every day. Try moving the receiver antenna (borrow a portable) away from the house and other buildings. That will at least show if the background noise is local or distant. If local, treat the source or raise your antenna mount; if distant, the suggested yagi might be necessary.


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PostPosted: Mon Jan 30, 2017 5:19 pm 
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Joined: Wed Mar 10, 2004 2:32 pm
Posts: 139
Location: FB2 Simulcast
FYI, . . . as early December 2016, Oak Harbor PD is now operating a three-site FB2 simulcast arrangement - using new GTR8000 equipment - positioned @ both Mt Erie, Oak Harbor and Camano Island, each adjusted at at 25 watts.


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