Attic antenna

[rapidcharger]

I would recommend against the yagi unless you are also trying to attenuate other signals from outside areas. They are just too hard to position for the reward in gain you get.

Get a omnidirectional/vertical. Attics in florida are not usually tall like they are in other states to the north. You probably won't have room for a big one but if the repeater is only 10 miles away, you frankly should be able to do that with a coathanger.

I run some infrastructure at my house and all of my antennas are now in the attic. Not as ideal as if they were outside but being 225'-400' above surrounding terrain, it does just fine and I don't have to worry about the weathering of the antennas or feedline. Desense and electrical noise around the house, yes.

 

[jk77]

I can get into repeaters 10 miles away from my living room with my 5 watt HT and a 14 inch whip. It doesn't really take that much.

However, I want to reach repeaters much farther away (15 or 20 miles out) so I have decided to hang up an N9TAX slim jim. I just ordered it and should be receiving it in the next few days and will keep you updated on how well that experiment goes. It's only 5 or so feet long and should be great for anyone with deed restrictions or who live in an apartment. It can basically be hung anywhere as long as it's away from metal. Of course, the higher, the better and the attic sounds like a good place for it.

 

[jk77]

Well, I received my Slim Jim yesterday. So far I'm less than overwhelmed with its performance. I'm assuming the problem is with my configuration. I'm going to try moving it around to various locations and see if I can't get better performance out of it. I'm somewhat limited in what I can do though. So far it has not allowed me to hit any additional repeaters that I couldn't already hit with my 14" whip. It does very good for reception however.

 

[jk77]

Ok, so today I moved the N9TAX antenna to a different location and was able to hit a repeater 20-25 miles away with an HT! Plus, I got a good signal report. If I could put it up in an attic, I'm sure I would pick up at least one more repeater. I'd say that it's a good option for anyone looking for an attic antenna. It's very easy to set up and move around if needed.

 

[N1XDS]

Sorry for my late reply I got tied up with checking connections at the antenna I went with the Hustler G6-440 antenna and I am noticing a problem maybe not a problem though. Yesterday, I had troubles accessing the local DMR repeater in my area the guy in my area had to mess around with the coax connection to make it work and I was picking up the repeater just fine and hearing people talking and now I am showing a X on my LCD screen but I can hear people just fine with no problems whats so ever. But earlier today I had 1 bar signal coming from the repeater and same with people talking as well on North America talk group so am not sure what the issue is? Should I check the radials & coax connections by the antenna and connector? I made sure they were on tightly and not over snugged.

I don't know anyone around my area that will help me find the issue and help me fix it it's located in the attic. I have asthma and I have to becareful going up there cause of the dust. If anyone in the area of Valrico, Florida 33594 which is a town outside of Tampa/Brandon area who deals with these type antennas I would be more than happy to pay some one out of pocket for their time.

Perfect SWR's 1.1 accross. I have no idea what to check.

- Jamie

 

[Netdewt]

[Replying to Netdewt] The Radio Shack 20-176 is likely to outperform a homebuilt 2M ground plane if you've never built one before. And maybe even the MFJ-1740 in the GigaParts link you provided. And you have some good testimonials right here on the 20-176.
If you can more easily run coax from the center of the house to the distant ends of the house (in the attic)... and can hide the coax more easily, then do a couple of runs now even if you don't use them. But if you don't care if those runs are visible in the attic, then no need to install them now.
I was suggesting two widely separated runs so that you'd have more options if you start using two antennas, e.g. separation so they don't affect each other TX/RX, having more flexibility to select optimal placement in the attic, etc.

I think I'll get the Radio Shack 20-176.

Can you guys recommend a specific cable? I need 50ft x 2, don't want to mess with crimpers, etc.

The attic space I am using is not very big or accessible, since most of it is finished livable space. I need to put in additional access panels wherever I put an antenna. There is already one near the HDTV antenna. Can the 20-176 be close to that?

Sorry again N4CYA.

 

[jk77]

Can you guys recommend a specific cable? I need 50ft x 2, don't want to mess with crimpers, etc.

I'm not sure how to insert links here, but take a look at this page:

Coaxial Cable, Coax Cable Preassembled


As you can see, it all depends on how much you are willing to spend. You want to make sure you get 50 Ohm cable.

 

[mmckenna]

Since it sounds like you are interested in amateur UHF and the like, I'd recommend something better than what you'd find at Universal Radio. For 50 feet at UHF frequencies, LMR-400 would be the minimum I'd personally choose. I'd probably want something more like LMR600 or 1/2 inch heliax. If you ever decide to mess around in the 900MHz or 1200MHz amateur bands, you'll want something better than RG-8/RG-213. Those cables would work fine, but since you are putting the effort into a new install and want to do it right, don't short change yourself by doing all this work and pulling in an inferior cable. The price difference will be minimal.

 

[Netdewt]

Since it sounds like you are interested in amateur UHF and the like, I'd recommend something better than what you'd find at Universal Radio. For 50 feet at UHF frequencies, LMR-400 would be the minimum I'd personally choose. I'd probably want something more like LMR600 or 1/2 inch heliax. If you ever decide to mess around in the 900MHz or 1200MHz amateur bands, you'll want something better than RG-8/RG-213. Those cables would work fine, but since you are putting the effort into a new install and want to do it right, don't short change yourself by doing all this work and pulling in an inferior cable. The price difference will be minimal.

Maybe I'll just run 1. I can't possibly plan for all future situations, I don't even have my license yet, I don't really know what I'm doing. I just want a decent antenna when I am ready. I can always add an outdoor antenna if needed.

I'll look for a finished 50ft lmr 400/600. Looks like min $50 for that cable.

Maybe this?
http://www.amazon.com/gp/aw/d/B005DVAA9W/ref=mp_s_a_1_2?qid=1413758729&sr=8-2&pi=SX200_QL40

 

[mmckenna]

Make sure you are getting real Times Microwave LMR400. There are a lot of cheap knockoffs out there. There are a lot of sellers on Amazon as well as e-Bay that are claiming to sell real Times Microwave cable, but it isn't.

Here ya' go, run 9 all at once! Only $13.00 a foot, $10.21 a foot if you have an account:
https://www.tessco.com/products/displayProductInfo.do?sku=340724&eventGroup=4&eventPage=1

 

[scannermanner1]

Make sure you are getting real Times Microwave LMR400. There are a lot of cheap knockoffs out there. There are a lot of sellers on Amazon as well as e-Bay that are claiming to sell real Times Microwave cable, but it isn't.

Here ya' go, run 9 all at once! Only $13.00 a foot, $10.21 a foot if you have an account:
https://www.tessco.com/products/displayProductInfo.do?sku=340724&eventGroup=4&eventPage=1

WOW that's some serious coax !! Never seen anything like it before.
that would be way nicer then 9 separate runs!!

 

[AK9R]

The DX Engineering 400MAX cable is equivalent to Times LMR400 and is made in the U.S. I've purchased a couple of their coax cable assemblies and I'm happy with the quality.

Cable Xperts also has cable assemblies using Cinta 400 cable which I believe is an Andrew product equvalent to LMR 400. Their assemblies are also good quality.

In general, I would not buy from an Amazon retailer as you really don't know what you are getting and I don't think Amazon vets those resellers very well.

 

[Netdewt]

PL 259 on both ends?

 

[scannermanner1]

PL 259 on both ends?

If below VHF hi,170MHz than a pl259 would be ok, but anything higher then that then I would say use a type-N

 

[W9DWP]

I have had good luck with the Jetstream JTB-3 dual band antennas that I have gotten from R&L electronics.
They are a little over 4Ft tall and should fit in most attics.. You may want to try to mount it to your the rear of satellite dish antenna.. I have been using the LMR-240 or LMR-400 cable for a long time. I have the proper crimper for the LMR-240 and LMR-400 connectors, they are easy to put on if you read the instructions. The crimp on connectors are better than they were years ago.

 

[rapidcharger]

R&L doesn't let you return antennas though so that might not be a good place to buy one if there is a chance it won't work for you.

 

[cpfinlay]

I was also faced with the HOA restriction, but had the additional complication of the energy efficient "tek-shield" roof, which basically acts as a big RF tin foil hat for the attic.

I decided to use a Ventenna dual band VT-27. I had a vent near the crest of the roof and mounted it there. That placed it at about 50ft, and I fed it using LMR400. It has been there for several years and works VERY well.

I also have one for SWL (Ventenna VT-SWL) and scanner operations (home made).

Ventenna: Untitled

 

[K3JTP]

Here's a twist. Just passed Technicial and grandfathered into General; 100W Xceiver. Want to work HF SSB (80-40-20), but antenna choices limited to dipole or long wire. Tried tuning existing SWL random long wires and set off home alarm smoke detectors at 50 watts. Thinking about installing attic dipole with ferrite chokes around any of the alarm wires in attic. Are there loaded dipoles or anything else commercially available that would fit 40' attic and be at least modestly effective?