scanner antenna positioning

Status
Not open for further replies.

jheitman

Member
Joined
Jan 28, 2017
Messages
22
Location
Sun City West
Just found out I can't have any external antennas in my neighborhood.

So I'm thinking about an attic installation with various broadband, Yagi and maybe a diople..

I want to install antennas for HF, VHF and UHF.

Here is my concern. My home has TILE ROOFING, maybe concrete tiles.

Does anyone have any data on propagation through such a roof?

I've had good luck installing in an attic with asphalt shingles, but I have no experience with tile roofing.

Before I spend money and time I thought I'd ask first.

Jim
 

jheitman

Member
Joined
Jan 28, 2017
Messages
22
Location
Sun City West
The sides of my house are also stucco, which I think is applied over a metal mesh.

Anyone have experience with this, too?
 

w1bp

Member
Premium Subscriber
Joined
Jul 8, 2014
Messages
29
The sides of my house are also stucco, which I think is applied over a metal mesh.

Anyone have experience with this, too?



That's a tough situation. I'd look to what ham radio ops do in these situations.

Do you have a patio or a shed? Could you put up a flag pole? Think of things you are allowed to have in which you could hide an antenna.

There is a company that makes decoy vent pipes for roves that hide antennas.

Get creative and look for permitted places to hide an antenna.


Sent from my iPhone using Tapatalk
 

ko6jw_2

Member
Premium Subscriber
Joined
May 18, 2008
Messages
1,448
Location
Santa Ynez, CA
You will only be able to determine propagation in your situation by experiment. It will clearly vary by frequency. Look at it another way, even if there was a table to look all of this up, you can't change the parameters. For HF you might be able to use a stealth wire antenna out side. At VHF and UHF frequencies some sort of directional antenna might helpful. I've never used or talked to anyone who use a vent antenna, but they've been around for a long time so I suspect that they work. Anything outside is better than something inside. Good luck.
 

jheitman

Member
Joined
Jan 28, 2017
Messages
22
Location
Sun City West
I need an Yagi for local public service Simulcast 769-774. That would be one to experiment with in the attic.

Then I thought I could make a little cluster of three omni mobile whips tucked under the inside eve of a 2nd story dormer.
2m & 70 cm Tx-Rx
136-512 MHz Rx
800-950 MHz Rx

How far apart would the whips need to be to function Independently

Jim
 

cellphone

Silent key.
Premium Subscriber
Joined
Dec 28, 2002
Messages
1,811
Location
Ahwatukee, AZ (Phoenix)
For a yagi, here is what I use:
746 - 787 MHz (LTE Band 13) 7 dBi LTE Yagi Antenna - Rfwel Engr E-Store

You can get higher gain versions depending on your need, but this one is good for the price.

Having antennas in the attic is better than nothing. Ideally, you would like them as high as possible outside, but this is a good compromise to adhere to HOA. I have numerous antennas in the attic. The attic reception is MUCH better than anything in the house.

Regarding antenna spacing, I would say you would be ok with receive antennas spaced 1-2 feet apart. Keep the transmitting antenna as far away from other antennas as possible to prevent damaging the front end of your receivers. I would say a minimum of 5 feet or more if you are running a lot of power. In the past, I have run a 50 watt 2m about 3 feet from a scanner antenna on my car with no issue.

Search the antenna forum, or ask questions there if you cannot find the info you need. You will likely get more/better responses there.

Scanner / Receiver Antennas - The RadioReference.com Forums
 

ermin

Member
Joined
Dec 21, 2007
Messages
360
Location
Jacksonville Florida
Just found out I can't have any external antennas in my neighborhood.

So I'm thinking about an attic installation with various broadband, Yagi and maybe a diople..

I want to install antennas for HF, VHF and UHF.

Here is my concern. My home has TILE ROOFING, maybe concrete tiles.

Does anyone have any data on propagation through such a roof?

I've had good luck installing in an attic with asphalt shingles, but I have no experience with tile roofing.

Before I spend money and time I thought I'd ask first.

Jim

I have had a VHF/UHF antenna in my attic peak surrounded by a tile roof for over 20 years. It works great. And, living in Florida less than 2 miles from the Ocean the antenna still looks brand new. I use it for 2 meters and 70 Cm but it works great on my scanner for 800Mhz also.

73

Ermin
 

BillH1

Member
Joined
Dec 4, 2016
Messages
111
Location
Golden Valley AZ
When I lived in an apartment I just stuck a magmount to either a pie pan on the fridge, or on the window frame. Worked 1000x better than the antenna on the handheld. If you can put up a small flagpole, I have seen people disguise them as antennas.
 

jheitman

Member
Joined
Jan 28, 2017
Messages
22
Location
Sun City West
I'm concerned about the stucco gables which extend all the way to the peak at each end of the house.
Tight metal screens are under the entire stucco coating.

The paths through the roofing are North ans South with solar panels covering much of the south view.....

My rear patio cover is Aluminum, I wonder if it will take my weight????

I guess I could put one whip on the top of a flag pole....
 

n0doz

Member
Premium Subscriber
Joined
Jan 11, 2006
Messages
764
Location
Metro PHX AZ
Another trick: PVC pipe containing a whip, painted to match the house and attached to a wall outside. You can put that up near the roof and no one would be the wiser.
I've used the Ventenna for VHF... works great. They make commercial band versions in addition to the ham units.
 

jheitman

Member
Joined
Jan 28, 2017
Messages
22
Location
Sun City West
A PVC Radome sounds interesting.
However, don't mobile whip antennas need a ground plane? Like the roof of a car?

If I mount say three whips, covering different bands, on a flat platform elevated a little above my Aluminum patio roof, don't I need to provide a conductive, grounded, cover on the platform surface, for a ground plane?

Isn't this what radial elements are for?

Jim
 

w1bp

Member
Premium Subscriber
Joined
Jul 8, 2014
Messages
29
A PVC Radome sounds interesting.
However, don't mobile whip antennas need a ground plane? Like the roof of a car?

If I mount say three whips, covering different bands, on a flat platform elevated a little above my Aluminum patio roof, don't I need to provide a conductive, grounded, cover on the platform surface, for a ground plane?

Isn't this what radial elements are for?

Jim



I believe the ventennas are vertical dipoles, which do not need a ground plane. You could make a vertical dipole yourself using two mobile whips.

Could you put some stubby antennas on the frame of your solar panels? If anyone asks, you could say they are part of the system. The panels themselves are DC, so they might not be too noisy.


Sent from my iPhone using Tapatalk
 

jheitman

Member
Joined
Jan 28, 2017
Messages
22
Location
Sun City West
I was going to put a couple whips on my patio cover, which is Aluminum and from the best I can find, it is not to be walked on.
So now I'm down to attic mounts, and hidden mounts like Ventennas.
I need a 750 MHz Yagi to reject Phoenix PD Simulcast towers.
I need to find a 2m and 70cm directional dual band.

I could put both on a rotor in the attic,on a tripod.
Any rotor recommendations?
 
Status
Not open for further replies.
Top