Solution for getting reception in a valley

[CastleBravo1954]

So I am trying to use an SDR to do some scanning of my local P25 Frequencies. I live in a valley. When I take my SDR with my antenna up on a hill, I have zero problems with reception. When I drive about 2.5 miles away to my house, I lose ~30 decibels of reception. I realized that the towers I am trying to monitor are shooting right over my house. I can sometimes get the control frequency at my house with my crappy antenna. The frequencies I am trying to monitor are in the 700 and 800 Mhz bands. Are there any antennas here that could work for my use case?

 

[rf_patriot200]

So I am trying to use an SDR to do some scanning of my local P25 Frequencies. I live in a valley. When I take my SDR with my antenna up on a hill, I have zero problems with reception. When I drive about 2.5 miles away to my house, I lose ~30 decibels of reception. I realized that the towers I am trying to monitor are shooting right over my house. I can sometimes get the control frequency at my house with my crappy antenna. The frequencies I am trying to monitor are in the 700 and 800 Mhz bands. Are there any antennas here that could work for my use case?

The sky is the limit, so Try to get your antenna in the sky !

 

[mmckenna]

Antenna gain may help you gain some of that loss back, but usually topographical shielding like that is going to require getting your antenna way up high to see over the hill.

You could try a 700MHz Yagi antenna, but you'll still want it up as high as you can get it, and you'll need really good coaxial cable to get that signal down to your radio. Even with all that, it may not work well enough to get a solid decode.

 

[prcguy]

Do you know anyone that could host your SDR receiver and antenna at a better location then run it remotely from there?

 

[Omega-TI]

I know this is going to sound weird, but it worked for me years ago...

1) Get out your binoculars, look for a metal building higher up on the hill surrounding your location.
2) Aim your Yagi at that building.

If you get a few decibels of gain from the reflected signal, invest in a pre-amp.

 

[CastleBravo1954]

The sky is the limit, so Try to get your antenna in the sky !

I would have to have a 100 foot tall tower to get to the elevation of where I was at. That does not meet the Wife Approval Factor nor can I afford it.

Antenna gain may help you gain some of that loss back, but usually topographical shielding like that is going to require getting your antenna way up high to see over the hill.

You could try a 700MHz Yagi antenna, but you'll still want it up as high as you can get it, and you'll need really good coaxial cable to get that signal down to your radio. Even with all that, it may not work well enough to get a solid decode.

That's what I figured

Do you know anyone that could host your SDR receiver and antenna at a better location then run it remotely from there?

Nope, that's why I am here

I know this is going to sound weird, but it worked for me years ago...

1) Get out your binoculars, look for a metal building higher up on the hill surrounding your location.
2) Aim your Yagi at that building.

If you get a few decibels of gain from the reflected signal, invest in a pre-amp.

I don't have a metal building I could aim at. Would a hill work?

 

[mmckenna]

Sounds like you are kind of stuck. You could try a high gain Yagi and see if you can get some reflections from hills/buildings, but that's really kind of like throwing mashed potatoes at the wall and hoping it sticks.

Without remote receivers, or hoping someone streams what you want to hear, there's not much you can do. Topographical shielding is a real thing and there's no easy/cheap way around this for a hobbyist.