Scanner Antenna help.

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This is my first outdoor antenna I put up. Brand and model is unknown. Was given to me for free.

On the 800 the local EDACS about 5 miles me has like a squelch at the end of a transmission. On the rural fire department's VHF 150. I get bleed over audio some times from the weather band. This is from the outdoor antenna hook straight to my 996XT

With the stock antenna none of this ever. The 800 sounds better.

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kb2vxa

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I can't narrow down your problem because you don't give any specific information except for bleed-over from the weather band. Therein lies the clue, the outdoor antenna provides much stronger signals than the "stock" one. If you consider the situation problematical you'll have to deal with it from the receiver end of it.

The only part that doesn't involve the receiver is the 800MHz band. That is an antenna and/or coax problem, trouble here is the antenna isn't too hot on 800 to begin with. Things can be improved by using the lowest loss coax available within your budget, the usual RG-8 and clones doesn't cut the muster on 800 and RG-58 is out of the question except for mobile where length is 18' or less.
 
Joined
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842
Location
Lincoln, NE
I can't narrow down your problem because you don't give any specific information except for bleed-over from the weather band. Therein lies the clue, the outdoor antenna provides much stronger signals than the "stock" one. If you consider the situation problematical you'll have to deal with it from the receiver end of it.

The only part that doesn't involve the receiver is the 800MHz band. That is an antenna and/or coax problem, trouble here is the antenna isn't too hot on 800 to begin with. Things can be improved by using the lowest loss coax available within your budget, the usual RG-8 and clones doesn't cut the muster on 800 and RG-58 is out of the question except for mobile where length is 18' or less.
Thank you for your input. I am thinking about buying a new antenna and coax. Only thing is, I really would like help from someone local to help install it.

Do you think there could be interference from from mobile towers close by? I think there are 3-4 different ones well then 1/2 mile.

If you want to take a satellite view of the area my address is 6007 N 14th St Lincoln,NE and they are just west from that address.

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TeRayCodA

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Muskogee,Oklahoma
What you have there,is a ChannelMaster 5094 "Monitenna"(one of the finest scanner antennas ever built) as a matter of fact,the highly regarded Scantenna is modeled after those.ChannelMaster has long since discontinued those.I ran one for years,they were great!
Yours looks like an early model without the parasitic 800Mhz element.(later,they added another element on the bottom for 800Mhz,hence,the model 5094A)
Did you by chance change out the balun transformer with a new one when you put it up?
Based on a half-wave"dipole cluster" design.They came with 50ft of RG-6 premium coax cable.
 
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Lincoln, NE
What you have there,is a ChannelMaster "Monitenna"(one of the finest scanner antennas ever built) as a matter of fact,the highly regarded Scantenna is modeled after those.ChannelMaster has long since discontinued those.I ran one for years,they were great!Yours looks like an early model without the parasitic 800Mhz element.(later,they added another element on the bottom for 800Mhz)
Did you by chance change out the balun transformer with a new one when you put it up?
Based on a half-wave"dipole cluster" design.
I have no idea what a balun transformer is, so I have not. i'm new new to this part
 

ak4fn

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Fredonia, KY

That is the 300 to 75 ohm balun transformer. They are very easy to over tighten, but you can get a replacement from RadioShack Matching Transformer : Transformers | RadioShack.com Like the previous post mentions good coax will make a big difference in the 800 range. LMR400 or 9913 even RG11 are a good choice. If you know anyone that installs cable they may have the rg11 to sell for cheap (that is how I got mine, 100 ft with ends put on for 12.50).
 

Mtnrider

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Greene County New Yawk
Your problem with the antenna is its GOOD...i have had many flavors over the years and this style works real well for me, Although i dont have any 800's to listen to around here, UHF and VHF work great..even with the el cheapo coax at 50 foot long. I have had a few baluns go bad over the years but thats about it.
 

ak4fn

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You may try use attenuator with that frequency that your local fire dept uses and see if it helps any.
 

TeRayCodA

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No,an "N" connector will not work on the transformer.You just need a good length of RG-6,or,RG-11,with the proper "F" connector installed.It is just good advice to go ahead and change the transformer,along with new coax.
 
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