What is a good antenna to construct for a repeater?

[centuryvrproductions]

I am looking to build an antenna for my repeater. one that will have some gain.

I was using a ground plane antenna made from a welding rod but it had no gain so its time to upgrade... any suggestions?

 

[OCO]

J Pole or find a good one here . There's at least a couple of collinear designs using pieces of coax soldered center conductor to shield that should be easy for you.. put the finished work in a piece of rigid plastic pipe..

 

[centuryvrproductions]

for making the j-pole, can i just solder RG-8 the way it is in the instructions or do i have to use the brass tubing?

also i am using aprximitleey 25-30 watts on the repeater so will it work ok and what is the gain?

 

[jaspence]

Repeater antenna

If this is a simplex repeater, then a simple j-pole is an excellent choice. The "copper cactus" design works well and is durable. If this is a half-duplex repeater, there is more involved than just connecting an antenna. Take a look at Repeater101 for more information.

 

[centuryvrproductions]

I have it all setup and working with at duplex with duplexer and low loss Heliax feedline to a 55ft tower space... i just need a better antenna

444.500 +5MHz


will the antenna still work?

 

[jaspence]

The antenna will work, but if you read the linked article, the author's suggestion that a high quality antenna is desirable is the real answer for best gain and coverage. Make sure that you use good lightning protection such as a PolyPhaser. Is this a new repeater? I cannot find any information in the ARRL Repeater Directory, Artsci websight, or in the MARC Repeater Directory. What is the callsign?

 

[centuryvrproductions]

The antenna will work, but if you read the linked article, the author's suggestion that a high quality antenna is desirable is the real answer for best gain and coverage. Make sure that you use good lightning protection such as a PolyPhaser. Is this a new repeater? I cannot find any information in the ARRL Repeater Directory, Artsci websight, or in the MARC Repeater Directory. What is the callsign?

yes I jsut put it up, I am still constructing the antenna system so once I get it setup, I will be coordinating it.

This is the KB1VSP Repeater Milford CT

The KB1VSP Repeater

 

[N5TWB]

yes I jsut put it up, I am still constructing the antenna system so once I get it setup, I will be coordinating it.

This is the KB1VSP Repeater Milford CT

The KB1VSP Repeater

Hmmmm, cart before the horse. SOP is coordinate, get approval to construct, then construct and put on the air.
At least, that's my observation of the process in my area.

 

[centuryvrproductions]

Hmmmm, cart before the horse. SOP is coordinate, get approval to construct, then construct and put on the air.
At least, that's my observation of the process in my area.

So will the antenna work with RG-8 or RG-58 with out the brass tubing?? im not going to be using it until it coordinated in case of interference anyway

 

[W2NJS]

While many of us admire your enthusiasm, you really should get an antenna design book and learn about what you're trying to do from more than a cut-and-try standpoint. It will save you a ton of time and possibly wasted effort.

 

[prcguy]

If your good with hand tools and have a UHF antenna analyzer a 4-bay dipole array would be my recommendation. The antenna can be made very easily from some 1/2" copper pipe and PVC fittings with RG-6 coax for the phasing harness.

Several years ago a RR member needed a high gain VHF antenna so I designed a fairly easy to build VHF version shown in post 5 here:
http://forums.radioreference.com/antennas-coax-forum/109144-4-bay-vhf-dipole-array-project.html

The antenna can be scaled for UHF and would be about 6ft tall not including some mast overlap for mounting. For VHF/UHF an exposed dipole array of this type will give the most gain possible for its size.
prcguy

 

[centuryvrproductions]

Diamond X30A Dualband Base/Repeater Antenna | eBay

is this a good repeater antenna?

it claims to have up to 5.5db gain on 440

 

[prcguy]

Based on other known antennas of similar size and construction I would say the dB rating is in dBi and not dBd. Compared to a 6dBd gain 4-bay dipole array it would have about 3.1dBd gain.
prcguy

Diamond X30A Dualband Base/Repeater Antenna | eBay

is this a good repeater antenna?

it claims to have up to 5.5db gain on 440

 

[NDRADIONUT]

Get a Diamond X-50

 

[W2NJS]

You do not need a dual band antenna when the repeater operates on only one band, obviously. You are much better off with a single band antenna.