CHP again.....

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E5911

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I am not sure if this has been brought up, probly has but here goes. I have a pro-197 in the car that I listen primaraly to trunked systems with. However I also listen to CHP. Im on the western border of Az and Ca so reception is not the greatest. I would like to run 2 antennas, but am not sure how to do it, or wheather it ia advisable. Can someone help?
 

Mojaveflyer

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Two Antennas For One Scanner

Radio Shack has a "T" connector that has male BNC connectors to couple with two cables from antennas and a female connector to attach to the back of the radio. I run a GRE PSR-600 in my car so I added a home made adapter with a short piece of coax and a FM Radio Trap in line to reduce intermod in the PSR-600. Made a new radio out of the -600...
 

gmclam

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Radio Shack has a "T" connector that has male BNC connectors to couple with two cables from antennas and a female connector to attach to the back of the radio.
I hope it is not just connecting the antennas directly together. Can you give us the RS part number or link to it? Thanks.
 

gmclam

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One great antenna trumps 2 so-so antennas

I have a pro-197 in the car that I listen primaraly to trunked systems with. However I also listen to CHP. I would like to run 2 antennas, but am not sure how to do it, or wheather it ia advisable.
You've pretty much described my listening scenario when mobile in my home area. My county (Sacramento) uses a trunked radio system on 800MHz but I am equally interested in CHP. I think a far better solution is simply to get one antenna that works great in both bands.

Splitters in reverse, combiners, shorting the antennas with a T and other similar approaches all have drawbacks. Nothing beats a great antenna. Myself I have a couple of different magenetic mounts that each work great. They are spec'd for frequencies from 25 MHz to at least 1GHz, more than I need on both ends of the spectrum. There are tons of models/brands out there and in various mounting methods.
 

Mojaveflyer

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CHP Again...

The "T" connector from Radio Shack I was referring to is the '278-112' available at most stores or through their website for about $5. I use it to connect a 1/4 or 1/2 wave antenna for VHF/UHF and the modified Larsen 6 meter antenna cut to 42.5 MHz. Since you're only listening it should do fine.
 

avtarsingh

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all you need to listen to chp and 800 is a VHF quarter wave antenna NO COIL

it will receive CHP good enough in your area and works well on uhf and 800

example - if you are in most areas of sacramento mobile with a vhf qtr wave

expect to hear chp gold - chp black chp blue
and chp green all 3 chans used by sac and surrounding areas
what you will prob NOT hear.. is chp white because of the distance and rf signal using a vhf qtr wave antenna

if you just need to listen to whats going on around you (albeit 30-40 miles) vhf qtr wave will work great

they are cheap as hell its just an 18- 18 1/2 in wire with an nmo mount and is 1 of the best all around antennas
 

gmclam

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The "T" connector from Radio Shack I was referring to is the '278-112' available at most stores or through their website for about $5. I use it to connect a 1/4 or 1/2 wave antenna for VHF/UHF and the modified Larsen 6 meter antenna cut to 42.5 MHz. Since you're only listening it should do fine.
Since it is just a T, it is essentially shorting the antennas to one another. If a signal is received by both antennas, they will be mixed and could cancel one another out, giving you poorer reception.

You are far better off using some sort of combiner that is frequency based; ie signals below 100MHz and signals above 100MHz. Or better yet, just use one VHF/UHF antenna.

There are a LOT of antennas out there to choose from. I like a mag mount because I can remove it if necessary. One antenna means you only have to deal with a single coax. Here is one on ScannerMaster that is spec'd from 25MHz to 1000MHz for ~$40. I use something similar and have great range on CHP, not just the base units but mobiles too.
 
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E5911

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chp again

I placed a extra scanner in the outfit, a old radio shack model, with a 37mhz antenna i got from a local shop. the difference is fantastic, I may try a Diplexer, but for now this will do it.....

BTW interesting to hear "packet loss" on low band with the guys using 700.....
 
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