Basic GMRS Base Antenna Setup

[gman4661]

I have a friend who lives in the middle of three GMRS repeaters ranging from about 12 to 20 miles away. Using an HT, he can't access any of the repeaters from his home, but his radios work fine in other areas.

He is exploring options for a basic base antenna and coax. Ed Fong and J-pole antennas are possibilities with maybe a 20 foot mast. The terrain in the area is rolling hills. Suggestions for an antenna and coax would be appreciated.

 

[popnokick]

I have a friend who lives in the middle of three GMRS repeaters ranging from about 12 to 20 miles away. Using an HT, he can't access any of the repeaters from his home, but his radios work fine in other areas.

He is exploring options for a basic base antenna and coax. Ed Fong and J-pole antennas are possibilities with maybe a 20 foot mast. The terrain in the area is rolling hills. Suggestions for an antenna and coax would be appreciated.

Here are 24 possible choices. For coax use something such as LMR400 which is lower loss at the UHF freqs used by GMRS. You'll need a pigtail jumper to connect to the HT because LMR400 is a very thick, stiff cable. Use a short more flexible low loss jumper cable indoors -
GMRS Omni-Directional Base Antennas | The Antenna Farm

 

[prcguy]

I would not bother with a toy antenna like a J-pole, get a real antenna and enjoy some long distance. I would recommend the Comet CA-712 series tuned to 460-470MHz which is built similar to the original Stationmaster antennas but at a reasonable price. Stick that on a 20ft mast or whatever will get it above roof line and feed it with some low loss LMR400 and its GMRS party time.

Comet CA-712EFC 460-470MHz Base/Repeater Antenna

Comet CA-712EFC 460-470MHz Base/Repeater Antenna Comet CA-712EFC 460-470MHz Base/Repeater Antenna UHF Fixed station antenna 1.5:1 or less SWR: 460-470MHz Gain: 9dBi Max power: 200 watts Length: 10 ft 5 inches Weight: 2 lb 13oz Connector: N-

www.gigaparts.com

 

[nd5y]

Friends don't let friends use J-poles.

 

[W2JGA]

Friends don't let friends use J-poles.

What's wrong with J-poles? ...asking for a friend.

 

[sonm10]

Friends don't let friends use J-poles.

I use a slim jim, which is 2 j-poles together - I love it.

 

[nd5y]

What's wrong with J-poles? ...asking for a friend.

A lot of things. Poor patterns, feedline radiation, detuned by nearby conductive objects to name a few. Why do you never see J-poles in commercial or public safety installations?

 

[W2JGA]

I've seen a few, but the symptoms you mention seem like installation issues, not the design.

 

[mmckenna]

I've seen a few, but the symptoms you mention seem like installation issues, not the design.

The design is that it's a half wave antenna with a tuning stub and no ground plane. So it has 0dB gain, or the same as a quarter wave with a ground plane.

I ran a J-pole for a few years when I first got my ham ticket. Worked fine for my application at the time. Nothing wrong with them for amateur radio use.

It's easy to get a better performing antenna. There's nothing magical about a J pole other than they are super simple to make.

If it works for you, then that's all that matters.

As for the OP, the Ed Fongs are just wire inside a PVC pipe. It'll work better than a hand held inside the house, but for a few bucks more, you can get some gain that will improve things even more.

 

[W8UU]

Get something with decent gain (look for dBd numbers, not dBi) and something sturdy. Commercial-grade antennas are the gold standard but there are some decent ham-grade antennas that will suit your needs and purpose. Use quality feed line like LMR400, get it up as high as possible, and don't forget lightning protection. There are at least 30 choices out there on quality gain antennas for 460-470 MHz. The only limiting factor is what your checkbook can afford. Buy the best antenna you can afford. You'll get what you pay for.

 

[EAFrizzle]

It's easy to get a better performing antenna. There's nothing magical about a J pole other than they are super simple to make.

They're great as a field-expedient quickie for an HT (at least back when TV twin-lead was extra-cheap and available everywhere). The copper tubing ones are nice-looking in a steampunk way, but I wonder if the patina will affect the performance.

 

[mmckenna]

They're great as a field-expedient quickie for an HT (at least back when TV twin-lead was extra-cheap and available everywhere). The copper tubing ones are nice-looking in a steampunk way, but I wonder if the patina will affect the performance.

If the joints are soldered, then probably not. I'd probably be more concerned about them filling up with water, unless a weep hole was drilled.

 

[K5MPH]

J-Pole has no gain get an antenna that has gain ...........

 

[gman4661]

Very good replies. All are appreciated.

Apparently, the Ed Fong and J pole antennas aren't generally recommended.

Someone has suggested a Slim Jim which has twice the gain of a J pole. It's compact and very reasonably priced.

Comments please,.

 

[mmckenna]

Comments please,.

Why is this dude hung up on J-pole antennas?

Is it price? Maybe if you give us a budget for antenna/coax, we can make some recommendations.

I wouldn't pay for a J pole. Just too easy to make one on your own, or a similarly performing ground plane 1/4 wave.

 

[prcguy]

Very good replies. All are appreciated.

Apparently, the Ed Fong and J pole antennas aren't generally recommended.

Someone has suggested a Slim Jim which has twice the gain of a J pole. It's compact and very reasonably priced.

Comments please,.

I generally see two camps of GMRS users, one that uses various radios with really poor antennas and the other with various radios and really good antennas. The poor antenna crowd lives in a world that barely makes it out of their neighborhood where the really good antenna crowd is more worldly and can talk into other cities or counties. They usually run better radios but have learned the antenna is key to long distance and the cheaper radios are more of an annoyance picking up more interference and garbage but its really the antenna that puts them ahead of the poor neighborhood crowd.

So now is the time to decide, do you wanna live in a little world of just your neighborhood friends where everyone uses a J pole or do you want your radio signals to travel and see the world? That takes a real antenna up at real heights above roof line and short runs of low loss coax. Its your choice, pick a side and go for it. But if you pick the wrong side please don't ask why its not working well because deep down inside you will really know the answer.

 

[nd5y]

Someone has suggested a Slim Jim which has twice the gain of a J pole.

Slim Jims are just a J-pole with a longer radiating element that is folded over. They don't have more gain.

 

[W8UU]

Someone has suggested a Slim Jim which has twice the gain of a J pole. It's compact and very reasonably priced.
Comments please,.

You'd be ahead of the game just to buy a sturdy quarter wave ground plane.
Same (no) gain. Relatively inexpensive. Lasts forever.



.