GP-3 Questions

[W3AWF]

Yesterday I bought a Yeasu 7900R and a Comet GP-3 "LMR-400 also ovousely" With the weather being as hot as it is im not really looking forward to putting the GP-3 up. Would I be able to mount the GP-3 in my attic until the fall? "Or until I have access to my buddy's bucket truck"

 

[KK4DAN]

It depends what you are trying to reach? Are you just going to be talking into local repeaters (2m/440) and are they pretty close? If so, it probably shouldn't be an issue at all. It will definitely work better outside at higher elevations, but it will still work in your attic and local 2m repeaters (~10 miles) won't be any problem. You'll probably even be able to work some a bit further if that repeater antenna is higher up. You'll obviously work better on 2m then 440 just to the nature of their signals.

Heck, when I first started in Ham a few months ago, I was using a mag mount car antenna mounted on the side of an old PC case in my attic. It got me into all the local repeaters full quieting and even a few a bit further.

Since then I have built a collinear antenna ($10 total). I normally keep it up on a 20ft pole outside and the collinear is about 10ft tall total, so its about 30ft in the air. That gives me even better coverage. I need to paint it black to disguise it a bit in my yard and waterproof it better though, so I pulled it down yesterday and it sitting in my living room and although its not as good as being outside, it still reaches all my local repeaters just fine. I'd eventually love to get it even higher in the air, but right now it works great. Heck, at the 25-30' height I have it now, I can even hit a couple repeaters that are 60-75 miles away, but are higher in elevation themselves.

I actually am going to build another collinear antenna since they are so easy and cheap to build and give some decent gain and keep it in my attic so I can switch to it during storms when I disconnect my outside one.

When ever I head over to my parent's house in the next town over, I bring my HT along with my collinear so I can talk on repeaters near their place. Its pretty easy to carry in my car as the main part is only 8ft long.

 

[MTS2000des]

there can be a big difference in performance depending on several factors, what your home is made of has much to do with it. Any foil backed insulation in attic walls will definately attenuate RF. The presence of electrical (and newer houses), CAT-5 and other wiring or air conditioners can be a source of RFI.

If you can, it's best to mount the antenna outside. Where is up to you. Ideally the tallest peak in the roofline, AWAY from your AC power inlet (for safety and powerline noise). Install a good lignting arrestor inline (Polyphasers are the Cadillac, they cost, but it's what all the pro's use- go to any commercial site or cell site and that's what you'll see), and ground it properly. Invest in good feedline, for VHF/UHF, LMR400 is about the MINIMUM for anything over 50FT.

An old DirecTV "foot" make a great poor man's antenna mount, that and a 5-10 foot mast, is a cheap and easy way to mount an antenna without too much hassle. But I strongly suggest putting it outside if at all possible. Of course it all depends what you want to talk to and hear. Local repeaters within a few miles, inside the attic might be fine. if you want to get DX on simplex, you need to be outside and as high as possible.

 

[LtDoc]

When you get through with that bucket-truck, can I borrow it too??
Your antenna will probably work in your attic. There are some "but's" with that, as already posted, and how well it will work there is determined by your specific attic, location, etc. No guarantees either way. It's a matter of a signal getting through whatever is between the transmitting antenna and yours.
It's also a good idea if you can stand that antenna up vertically, as it was designed to work that way. Or, as vertically as possible anyway. Polarization comes into play, and that can make a huge difference.
Oh well, do what you can do until you can do it 'right'. That's what we all do...
- 'Doc

 

[N1BHH]

Rule number one in antenna construction, don't do it alone. Have some help around. You could mount the antenna anywhere practicable. If there is enough vertical height it will work, but you must remember that building materials will not allow for best performance with any antenna. Wait for cooler weather and mount it on the roof.

 

[W3AWF]

Well, I just got done putting the antenna in my attic "Still sweating from being up in that oven!". My house was built in 1986, so its basic insilation, basic roof, nothing foil backed. I made the mount with some pipe that I snagged from work. While I was up in the attic I found an old TV antenna, Would I be able to make that into an antenna for something? "Scanner, or HAM" Probably a dumb question but figured if anyone would know It would be somebody here.