Antenna location issues.

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KO4IPV

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I recently purchased a Can-Scan-III , was told it can be set up in my attic. I am concerned about maybe this location is not sufficient, should it be better suited on my roof ? I have the Bearcat 436 scanner, using RG-8 50 feet of coax. Only interested in frequency above 100.
 

KO4IPV

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An antenna will ALWAYS receive better when the pathway to the transmitter is clearer.

Also HIGHER is always better. It can "see" further.
Yes , okay but this type of antenna requires a metal base , should I install a metal base on roof or go to a pole mass ( metal) to satisfy this need ?
 

Ubbe

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If it is sufficient or not are hard for other people to know. The best way to test are to bring your 436 with you to the attic and try it out there, if you can receive the systems you want to receive.

If you want to receive as much as possible as further away as possible then mount the antenna on the roof. But try your 436 there first and try and locate the best place for the antenna. The other side of the chimney could give a totally different signal from a weak system.

What type of antenna is it? I can't get a hit on can-scan-III

/Ubbe
 
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should I install a metal base on roof or go to a pole mass
I'm not familiar with that antenna.

Is this it?
 

KO4IPV

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Since it's designed for mobile use, it would normally get its ground from the vehicle.

Some people use a cookie sheet or other metal object for a ground plane, but I'm sure some of our other members have better suggestions for using a mobile antenna at home.

Wait to see what they suggest.
 

KO4IPV

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If it is sufficient or not are hard for other people to know. The best way to test are to bring your 436 with you to the attic and try it out there, if you can receive the systems you want to receive.

If you want to receive as much as possible as further away as possible then mount the antenna on the roof. But try your 436 there first and try and locate the best place for the antenna. The other side of the chimney could give a totally different signal from a weak system.

What type of antenna is it? I can't get a hit on can-scan-III

/Ubbe
It is a CAn-Scan-III from DX engineering
 

IndyScan

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From the website: "Add an optional Larsen BSAKIT NMO Mast Mount and bend the radials downward at a 70 degree angle for best results." That's what you're going to mount this off vehicle. How were you going to mount it in the attic? What are you using for a ground plane?
 

KO4IPV

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From the website: "Add an optional Larsen BSAKIT NMO Mast Mount and bend the radials downward at a 70 degree angle for best results." That's what you're going to mount this off vehicle. How were you going to mount it in the attic? What are you using for a ground plane?
A metal file cabinet or a 3 by 3 metal sheet . I did see the option for the BSAKIT NMO mast mount but did not think I needed it , will not be using this antenna on my car. What. Say you
 

mmckenna

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A metal file cabinet or a 3 by 3 metal sheet . I did see the option for the BSAKIT NMO mast mount but did not think I needed it , will not be using this antenna on my car. What. Say you
The antenna will work better with a proper ground plane. The Larsen NMO base kit is a good solution, or you can build something yourself.

The antenna will work better the higher up it is. The frequencies your scanner and this antenna work on are usually considered "line of sight". If the antenna can "see" the transmitting antenna, it will work well. The higher up the antenna is, the better it will work.

Attic mounts can be hit or miss. It'll be closer to RF Interference from appliances inside the home. If your attic has HVAC ducting, metal pipes, wiring or foil backed/vapor barrier insulation, it can create issues. If your roof is made out of any metal, it's going to impact reception.
Even if the attic is entirely clear, any building materials will reduce signal strength slightly. Lightning protection is still required, an inch or so of roofing material is not going to protect the antenna, and even nearby strikes can induce enough energy into the antenna to cause damage.

RG-8 is not an ideal choice for coaxial cable, either. If you have not purchased it yet, you can do better.

So, get the antenna up high. For RX only use, it's going to work better with a ground plane. Use the best coaxial cable you can afford.
 

KO4IPV

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The antenna will work better with a proper ground plane. The Larsen NMO base kit is a good solution, or you can build something yourself.

The antenna will work better the higher up it is. The frequencies your scanner and this antenna work on are usually considered "line of sight". If the antenna can "see" the transmitting antenna, it will work well. The higher up the antenna is, the better it will work.

Attic mounts can be hit or miss. It'll be closer to RF Interference from appliances inside the home. If your attic has HVAC ducting, metal pipes, wiring or foil backed/vapor barrier insulation, it can create issues. If your roof is made out of any metal, it's going to impact reception.
Even if the attic is entirely clear, any building materials will reduce signal strength slightly. Lightning protection is still required, an inch or so of roofing material is not going to protect the antenna, and even nearby strikes can induce enough energy into the antenna to cause damage.

RG-8 is not an ideal choice for coaxial cable, either. If you have not purchased it yet, you can do better.

So, get the antenna up high. For RX only use, it's going to work better with a ground plane. Use the best coaxial cable you can afford.
I did order the NMO base kit (Larson) what is a better coax than rg8 please advise.there are no anything metal in my attic . And what is RX , you referring ? I am a newbie at this thanks for your help
 

mmckenna

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I did order the NMO base kit (Larson) what is a better coax than rg8 please advise.there are no anything metal in my attic . And what is RX , you referring ? I am a newbie at this thanks for your help
RX = Receive. Since this is the scanner topic/forum, we have to assume you are using this antenna for receiving only. Let us know if we are misunderstanding.

RG-8 gets suffers from a lot of signal loss as you go higher in frequency. Also, the longer you cable is, the more loss there will be. Ideally you want to keep the coaxial cable run as short as possible. You also need to use a better grade cable, if you want good performance on the higher frequencies (700 and 800MHz). If you really need 50 feet of cable, I'd recommend using Times-Microwave LMR-400 at minimum. If your cable needs to be longer, you may want to look at an even higher grade cable.
 

KO4IPV

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RX = Receive. Since this is the scanner topic/forum, we have to assume you are using this antenna for receiving only. Let us know if we are misunderstanding.

RG-8 gets suffers from a lot of signal loss as you go higher in frequency. Also, the longer you cable is, the more loss there will be. Ideally you want to keep the coaxial cable run as short as possible. You also need to use a better grade cable, if you want good performance on the higher frequencies (700 and 800MHz). If you really need 50 feet of cable, I'd recommend using Times-Microwave LMR-400 at minimum. If your cable needs to be longer, you may want to look at an even higher grade cable.
Receiving only yes that is correct
 
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