Handheld scanner has rough time decoding TRS

Starion

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I currently at the Springfield interchange, near west Alexandria, VA (where I-495, I-95, I-395). The scanner I am currently using is a Radio Shack Pro-651. It has poor reception on VHF. Reception is decent on 800 MHz but I have a hard time hearing Washington, D.C., Prince William County and Prince George's county trunked radio systems. I can hear Arlington, Alexandria and Fairfax county TRS just fine. I have poor reception with Virginia Stars even with a 21 inch antenna near a window. The handheld scanner does great outdoors away from buildings. Scanner receives analog signals just fine. I do hear some static though. I hear static when I listen to the buses on Fairfax County (P16) Trunking System, Fairfax County, Virginia - Scanner Frequencies I hear static on when I listen to the buses on WMATA system too. Airband and railroad reception is decent. NOAA weather radio sounds a bit scratchy. It would be a bit difficult for me to mount an outside antenna.

Ok, I guess I need to save some $$ to buy a used base/mobile scanner on Ebay. I guess the poor handheld can't cope with the strong radio signals overloading the receiver. Thanks for reading.
 

jonwienke

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Simulcast is also an issue, probably more so than overload. Wmata analog is garbage because their radios are garbage, particularly the metro trains. Their digital is simulcast, so reception is spotty for anything but the Uniden SDS models.
 

Starion

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Thanks for the information. I solved the issue regarding VHF reception. Now I can hear airplanes taking off and landing at Reagan Washington National Airport. I think something in the corner of my room is interfering with the scanner. Maybe the metal closet doors were attenuating some signals. The scanner seems to be doing fine on the other side of the room. Now I just need an electrical extension cord for the AC adapter to. I've been using battery power for the past 30 minutes. Bye.
 

Starion

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I just noticed that I have bad reception on VHF whenever the scanner is connected to the AC adapter. I'll try using another AC adapter.
 

jonwienke

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Cheap adapters generating RFI can bork reception. Using the Uniden USB cable with the ferrites helps block RFI from the adapter.
 

air-scan

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I just noticed that I have bad reception on VHF whenever the scanner is connected to the AC adapter. I'll try using another AC adapter.
May I suggest this?

You may need a cord with barrel connectors that fit the brick and the scanner. It will do 9v DC for your 651. 11000 mah will be all day before it halfway drains at half volume. Theoretically 55 hours at half volume.

Could run quieter.
 
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tvengr

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You have to remember that the cable on the ac adapter becomes part of the antenna system and can affect the directivity.
 

Starion

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Fairfax, VA
I guess the aluminum siding is affecting VHF-high reception. I may need to put an antenna outside the window somehow. Thanks for the replies everyone.
 

wtp

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that is where i put a spare TV antenna after a hurricane took out the 12 foot roof one.
just try not to put it next to metal antenna ductwork. or like i did try just above that.
and RG6 cable works fine. that is regular cable for a house.
 

Starion

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Sorry for the late reply but I got sick with a virus. I didn't have a chance to go to Prince william County to monitor their trunked radio system. Thanks for the suggestions. I discovered a paging system on 152.1800 MHz. My guess is that the paging radio is interfering with reception of VA STARS. The control channel for VA STARS Fairfax is on 152.2025 MHz right now. I seem to have better luck listening to with a 19 inch BNC antenna. I'm still thinking about putting up an antenna in the attic.
 

Starion

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I finally found a post that explains my situation on VHF.

I'll try listening to my scanner in different areas to see how it behaves on VHF, airband and CB radio.
 

Starion

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Fairfax, VA
This is my last comment before I try using an antenna in the attic. I just remembered that my house is on the side of a hill. When I walk home from the bus stop I can only see the roof of my house. The combination of the hill and simulcasting must be causing bad reception of Arlington County Trunking System, Arlington, Virginia - Scanner Frequencies and District of Columbia Trunking System, District of Columbia, District of Columbia - Scanner Frequencies. Maybe I can put an 800 MHz antenna on a mast in the back yard when I have lots of money. Thanks for the suggestion about RG-6 coax cable. I have not heard of that cable before.
 

Starion

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My friend let me borrow his FM notch filter. It didn't eliminate the odd interference on VHF. Now I notice the strong signal between 25 MHz and 174 MHz. I guess I'll buy a software defined radio to identify the noise on VHF low and high. The scanner shows a strong signal but the noise doesn't break the squelch. I turned the squelch down but I didn't hear anything unusual unless the scanner is below 30 MHz or so. In the CB radio band I hear a whining sound. At least I have no interference above 174 MHz. I'll post again after I analyze the VHF spectrum using my SDR.
 

Starion

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I put a ferrite choke on the AC power cable thinking I could eliminate the audio hum that I hear on NOAA weather radio. The hum is still there but now the scanner can decode the VA Stars Fairfax site. Odd. The VHF airband still shows a strong signal without modulation though. Ok, now I just need a better antenna for 700/800 MHz and I'll be good to go.
 

jonwienke

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May I suggest this?

You may need a cord with barrel connectors that fit the brick and the scanner. It will do 9v DC for your 651. 11000 mah will be all day before it halfway drains at half volume. Theoretically 55 hours at half volume.

Could run quieter.
I have one of those, and it will run a scanner for a long time. I did a test run using it to power a 536, and gave up after about 36 hours. The battery voltage had barely budged.
 

Starion

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Fairfax, VA
I might buy that rechargeable battery befor I go travelling. Then I don't need to use a whole bunch of AA batteries when I am outside of my hotel. Thanks for the tip. The battery is cheaper than I expected too.

I think my issue with VA STARS is that I accidentally programmed the Arlington site in addition to the Fairfax site into the control frequency list. The scanner was trying to lock onto the Arlington site all this time. After I deleted the extra frequencies the scanner locks onto the Fairfax site now. I don't remember programming the Arlington site into the trunking system at all.
 

jonwienke

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Glad you got things figured out. Let us know how you like the battery pack.
 
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