800 MHz UHF Vertcial VS. OmniX Scanner Base Antenna

vocoder

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I use 2 of the Omni antennas for 800mhz P25 phase2. I live on the stateline, so I listen to IL Starcom and IN Safe-T. I have good reception of both.
 

prcguy

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Thank you for your response, as I have limited knowledge on the subject, but in reading about multi-range vs. dedicated 800 mhz antennas this seemed to be the answer. I didn’t know if this was an exception because of how it was built. When you say 0dBd, does that translate to not pulling in signals stronger and from farther away? I know others have stated they had success with the Omni-X, but I am unsure on how much “more” I’d get from a dedicated 800 MHz antenna
An example for this might be you have a really weak hard to receive 800MHz signal on an Omni-X, changing to a 6dBd gain will make a very noticeable improvement with less noise. Going to a 9dBd gain will be even better. A signal that is only noise where you can’t make out any words on a Omni-X should be good copy on a 9dBd gain.
 

galligan122

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An example for this might be you have a really weak hard to receive 800MHz signal on an Omni-X, changing to a 6dBd gain will make a very noticeable improvement with less noise. Going to a 9dBd gain will be even better. A signal that is only noise where you can’t make out any words on a Omni-X should be good copy on a 9dBd gain.
Thank you for the info. I am on the county line and one uses 800 MHz and the other uses 700 MHz. Most of what I want to hear is in the 800 range. Would I still hear the 700 frequency with the 800 antenna since I’m so close?
 

prcguy

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Thank you for the info. I am on the county line and one uses 800 MHz and the other uses 700 MHz. Most of what I want to hear is in the 800 range. Would I still hear the 700 frequency with the 800 antenna since I’m so close?
As an example, if an antenna is rated 824 to 896MHz I would expect it to work but with some degradation at 769MHz. Hard to predict how much. There are models that will cover both 700 and 800MHz.
 

Ubbe

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Maybe Ubbe could chime in here and assist. Thank You ubbe!
It's a 3dB loss at 800MHz for a genuin LMR400 coax at 100ft. Not alarmingly much. Coax cost will be $150-$200. A more easy to install RG6 coax will cost $25 and will leave a lot of money to spend on amplifier, filters, attenuators and a splitter so that several scanners can be used and there will be zero attenuation from the antenna and some extra gain to overcome the high internal noise figure in a scanner.

If a weak signal are received it could be lost in noise if a coax attenuates 3dB and can never be recovered again. If amplifying at the antenna you raise the signal level 10-15dB and at the other end you attenuate the signal as well as any added noise from the coax when electrons and molecules are forced to move to transport the RF signal.

RG6 coax
Amplifier low noise that can still handle strong signals
FM broadcast filter
Bias-T
1-2 splitter
4,7pF capacitor bridged with a 560 ohm resistor to make signals EQ balanced independent of frequency, inserted in the bias-T or splitter
Pigtail cables or quality adapters

/Ubbe
 

Robertolson

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I’ve got the OmniX Antenna with 40 feet of LMR 400 on a 1 story house in the L.A / O.C border
It gets the 700-800 frequencies OK. The OmniX really shines in the VHF, as with All Muti Band
Antennas there going to shine great in one band and everything else OK.

I’m also looking for a 700-800 Antenna. Pcrguy eBay’s recommendation got me interested.
Still open to a yagi like this one.

 

prcguy

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I’ve got the OmniX Antenna with 40 feet of LMR 400 on a 1 story house in the L.A / O.C border
It gets the 700-800 frequencies OK. The OmniX really shines in the VHF, as with All Muti Band
Antennas there going to shine great in one band and everything else OK.

I’m also looking for a 700-800 Antenna. Pcrguy eBay’s recommendation got me interested.
Still open to a yagi like this one.

I have a few spare 800-900MHz 6dBi jobs that go down to 750MHz just fine and your not far from me. Got something to trade?
 
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