Antenna location and hardware needed

KO4IPV

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I just recently bought this antenna Compactenna is the brand name, this antenna is a Can-Scan- III . Will be using on my home because of HOA issues, I also purchased the Larson BSAKIT NMO Mast Mount. My question is can I attach this mount directly to the facia on my roof ? Or does this antenna require a magnetic mount to operate correctly? and is some type of pole required, I would prefer to attach directly on facia.
 

mmckenna

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The kit includes the mounting bracket, NMO mount and ground radials, so the only thing you need to add is the antenna with an NMO base and the coaxial cable.
You do not need a magnetic mount.
No pole is required, there are two mounting holes on the bracket that can be used to attach to the facia. You can add a pole if you want to raise it up above the roof.
 

KO4IPV

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The kit includes the mounting bracket, NMO mount and ground radials, so the only thing you need to add is the antenna with an NMO base and the coaxial cable.
You do not need a magnetic mount.
No pole is required, there are two mounting holes on the bracket that can be used to attach to the facia. You can add a pole if you want to raise it up above the roof.
Thankyou you are a great help
 

nessnet

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A mag mount, to operate properly is clamped on a metal surface big enough to be a ground plane for the frequency of the antenna.

Your Larson kit has those radials. Those are your ground plane. In order to operate 100%, they need to be omnidirectional (evenly spaced). I would think that'd be hard to attach to the side of a house. It is designed to mount to a pole, with enough length so that those radials can be bent 70º.

What about an attic, or chimney?
 

popnokick

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jaspence

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I have been using a Compactenna since they were first sold at Hamvention. I have a tall vehicle, and it is the only antenna that lets me park in the garage without hitting the top of the door frame. I talked to the inventor for several minutes, and it is the metal car roof that makes this antenna work. Running medium power (20 watts), I can easily work repeaters at 20 plus miles, and the SWR is below 1.5.
 

KO4IPV

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A mag mount, to operate properly is clamped on a metal surface big enough to be a ground plane for the frequency of the antenna.

Your Larson kit has those radials. Those are your ground plane. In order to operate 100%, they need to be omnidirectional (evenly spaced). I would think that'd be hard to attach to the side of a house. It is designed to mount to a pole, with enough length so that those radials can be bent 70º.

What about an attic, or chimney?
I can easily mount this in my attic, although I was informed that outside is much better for a clear path. And I have no chimney so I gues it will be a pole if you say it won’t fit on side of house (facia).
 

K4EET

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Canelo56, what exactly do you mean when you say that you are going to mount it on the SIDE of your house. You are not going to have it sticking out perpendicular to the side of your house are you?
 

KO4IPV

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As jaspence stated, the COMPACtenna does need a proper ground plane whether it be radials or sheet metal. I have two COMPACtennas and they work great. I see that Canelo56 just posted so I will post this now and see what was said.
Thank you for responding yes I have the radials ( Mount) So I will be using those on the exterior of my home anything else to add to this thread Would be appreciated what is your experience with this antenna mounted outside
 

KO4IPV

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Canelo56, what exactly do you mean when you say that you are going to mount it on the SIDE of your house. You are not going to have it sticking out perpendicular to the side of your house are you?
I plan to mount it on the corner facia of the roof if I need to add a pole I will but I would like to just attach it right to the facia if it if I can’t do that will be using a pole to get it a little higher
 

K4EET

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I plan to mount it on the corner facia of the roof if I need to add a pole I will but I would like to just attach it right to the facia if it if I can’t do that will be using a pole to get it a little higher
I guess what I am wondering, the COMPACtenna needs to be vertical. The radials that you have should be equally spaced around the base. That would mean that the COMPACtenna should be out from the facia board almost 19 inches so that the radials adequately clear the side of the house. Now if you could mount the COMPACtenna on a pole, say a PVC pipe or similar, the higher up you go and still keep the HOA Police "happy" the better the COMPACtenna is going to perform. As they say, higher IS better...
 

KO4IPV

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I guess what I am wondering, the COMPACtenna needs to be vertical. The radials that you have should be equally spaced around the base. That would mean that the COMPACtenna should be out from the facia board almost 19 inches so that the radials adequately clear the side of the house. Now if you could mount the COMPACtenna on a pole, say a PVC pipe or similar, the higher up you go and still keep the HOA Police "happy" the better the COMPACtenna is going to perform. As they say, higher IS better...
Great info thanks again
 

K4EET

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<snip> what is your experience with this antenna mounted outside
I have been using two COMPACtennas now for about two years. They perform amazingly well for their size and in my testing, have outperformed other antennas in the same size class. They are great for where clearance issues arise for vehicles and great for somewhat "stealth" issues when you make it look like a vent pipe coming off the bathroom (LOL :ROFLMAO: ).
 

KO4IPV

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I have been using two COMPACtennas now for about two years. They perform amazingly well for their size and in my testing, have outperformed other antennas in the same size class. They are great for where clearance issues arise for vehicles and great for somewhat "stealth" issues when you make it look like a vent pipe coming off the bathroom (LOL :ROFLMAO: ).
I have been using two COMPACtennas now for about two years. They perform amazingly well for their size and in my testing, have outperformed other antennas in the same size class. They are great for where clearance issues arise for vehicles and great for somewhat "stealth" issues when you make it look like a vent pipe coming off the bathroom (LOL :ROFLMAO: ).
will do great advice
 

JefK

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I have been looking for a good antenna for use for scanning. I wanted something a bit discrete to place on the window ledge of an apartment window that was not very visible. (Ie blends in)

I came across this thread and I am intrigued if this would be a good use for the uniden sds100 for scanning when at home?

A quick research indicates this might be the appropriate model for scanning?


In my case I don't need a magnetic mount since the window sill is wood, but would this be the proper NMO mount so it sits flat on the window sill?

Thanks for any insight!
 

mmckenna

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In my case I don't need a magnetic mount since the window sill is wood, but would this be the proper NMO mount so it sits flat on the window sill?


Thanks for any insight!
That mount will work. That's the nice thing about NMO mounts, they are pretty much the defacto standard in the LMR industry.

Ideally the antenna will want a ground plane under it, that's how it's designed to work, mounted on the body of a vehicle. For receiving purposes, it's not going to break anything if it does not have a ground plane, but it will work better with one. In your case, you could stick the magnetic mount to any flat conductive surface (does not need to be steel to work, but steel if you need the mount to stick). You could use a cookie sheet, pizza pan, or even aluminum foil.
 

KO4IPV

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I have been looking for a good antenna for use for scanning. I wanted something a bit discrete to place on the window ledge of an apartment window that was not very visible. (Ie blends in)

I came across this thread and I am intrigued if this would be a good use for the uniden sds100 for scanning when at home?

A quick research indicates this might be the appropriate model for scanning?


In my case I don't need a magnetic mount since the window sill is wood, but would this be the proper NMO mount so it sits flat on the window sill?

Thanks for any insight!
I bought the Larson NMO high frequency Magnetic Mount FME female 47.99$ I use this with the Scan-Can III Sold through DX Engineering
 

JefK

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So if I use a flat mount NMO connector on a flat metal desk would it suffice if the wood window sill would not? There is a glass and metal desk the window I was thinking of.
 

mmckenna

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So if I use a flat mount NMO connector on a flat metal desk would it suffice if the wood window sill would not? There is a glass and metal desk the window I was thinking of.
The large magnetic base provides some capacitive coupling to the ground plane. It's not as good as actually having a permanent NMO mount attached directly to the ground plane, as in a vehicle roof install, but it'll work.
Simply setting the antenna on top of the desk would not provide a ground plane, as there will be no direct connection to the ground plane, and no real capacitive coupling.

You could take a pie plate, cookie sheet, etc. and make a 3/4" hole in it and permanently mount the NMO mount. Then screw the antenna on to that.
 
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