P25 Antenna 700/800MHZ

[tomcat2702]

Hello Everyone.

I run a heavy traffic setup currently monitoring 7 MARCS CC's and covering a 5+ county radius. Currently and since inception, the setup has been ran off one of the Nooelec Rattlesnake m3 antenna's mag'd to a metal plate on a balcony at around 20 feet that feeds into an SMA splitter, then 3 RTL-SDR's and a RSP1B. I have the best reception from this one spot and no other, even from the top of an old TV antenna on the house at probably 30ish feet. It's the one in the bundle with the blue rings around it.
There is also a nooelec LANA being used in the line.

I guess the question is... is there something that anyone has found that performs better than this and or if someone with the knowledge can explain why the reception is so good on this cheap and small antenna from this one particular spot.

 

[dave3825]

Height, coax and splitter. How much total coax and what kind of splitter? Most splitters other than a multi coupler will reduce the signal to each sdr. And cheap coax on long runs will have more loss on 7/800 mhz. And an LNA could be too much and or bring in more noise. Is the LNA at the antenna or near the sdr’s?

 

[tomcat2702]

Height, coax and splitter. How much total coax and what kind of splitter? Most splitters other than a multi coupler will reduce the signal to each sdr. And cheap coax on long runs will have more loss on 7/800 mhz. And an LNA could be too much and or bring in more noise. Is the LNA at the antenna or near the sdr’s?

25 Foot of coax from the antenna to the splitter. The splitter is 4 Way Microstrip SMA Power Splitter, 500 to 6000MHz High Gain SMA Microstrip Power Splitter. The LNA is close to the SDR's.

But I'm not having an issue or complaining about the quality. My question is trying to understand why this performs so well and if anyone is aware of something that might perform better.

 

[prcguy]

This is a good 700/800/900 antenna and sometimes shows up in the $30 range on eBay and would be a noticeable upgrade. If your splitting the signal you would still need an amplifier upstream of the splitter.

L-Com 800/900 MHz 6 dBi Omnidirectional Antenna Item # HGV-906U | eBay

Enhance your radio frequency signals with this L-Com 800/900 MHz 6 dBi Omnidirectional Antenna. Designed for maximum gain and breadth, this antenna is perfect for enterprise networking and servers. Its omni-directional feature allows for a 360-degree coverage, while the 6.0 dBi gain boosts weak...

www.ebay.com

 

[dave3825]

The LNA is close to the SDR's.

Lna at the dongles would amplify what's coming in and if what's coming is has loss, the lna will not help. Lna at antenna will send down a much nicer signal. I am not familiar with the splitter but would like to see a link.

As far as that one spot, what's around you? Could just be where the signal travels the best.

What kind of boat?

 

[tomcat2702]

Lna at the dongles would amplify what's coming in and if what's coming is has loss, the lna will not help. Lna at antenna will send down a much nicer signal. I am not familiar with the splitter but would like to see a link.

As far as that one spot, what's around you? Could just be where the signal travels the best.

What kind of boat?

Yeah, I need to get an enclosure to get it up by the antennas. The pictured balcony is facing south over open water, trees east and west and north is blocked by the edge of the house as far as LOS goes.
The boat is the previous owners, ours is in winter storage right now waiting for warm weather.. a 26 foot pontoon with a mercury 150