A good external antenna setup for an ht

[beerftw]

So I am fairly new to gmrs, the common ht antennas are easy enough to figure out. My issue is at my house I am surrounded by other trailers with metal siding, and my trailer house has metal siding as well. Inside the house range is terrible, outside it depends on the direction. I want to get an external antenna setup that can connect to my handheld but can also be later used for a dedicated base station.

 

  My problem is I do not understand db loss or cable types enough to figure what setup would work good with the 5 watt output and not be counter productive. I have 2 ht types both baofeng gmrs locked fcc compliant versions. I already figure the antenna would have to extend beyond the height of the roof to get past the faraday cage row aka the trailer park.

[RoadApple]

Your assumptions are correct.  You will be well served by an outside GMRS antenna especially if you can get the antenna higher up in the air above all that metal.  GMRS radio operates in the 462/467Mhz UHF frequency range.  At high frequencies such as UHF, you can realize a lot of power loss via coax cable.  There are several coax options on the market depending on how much money you are willing to spend.  A reasonably low loss coax such as LMR-400 will help keep more of your output wattage going to your antenna rather than being lost in the coax.  Also try to keep the length of your coax as short as possible.

There are many, but here is a place where you can do a little reading on coax loss Coax Loss Calculator | KV5R.COM

[AdmiralCochrane]

RoadApple is correct.  All you need to know for your application is LMR-400 or equivalent, short length, but even more important HEIGHT. 

You are correct, you need your antenna higher than the surrounding metal radio frequency Faraday cage barricades.  In the VHF & UHF ranges the saying is: HEIGHT IS MIGHT.

[LegitByDefault]

Sounds like your radio works just fine, but being inside a metal box isn't conducive. A magnetic mount antenna on the roof thereby using the roof as a ground plane and gaining height over your HT. That is where I would start.

If you don't think that'll work, you can mount an extendable mast to gain height over the other trailers.

Be mindful of overhead lines.

[WSIF574]

Everyone has given great advice. LMR 400 you can’t go wrong with but will need a mount and NMO connector. Magnetic mount would work too but because you mentioned upgrading to a base station I would skip that. Antenna choice can be tricky( kind of ) some just work better than others just because of there SWR , frequency resonance, and other variables. But don’t over think it. May want to order a few different ones from Amazon and try them out and see how each one performs then keep the one that sounds best. 

[WRTT751]

A simple mag-mount antenna sitting on your roof should be viable. 15ft of RG85 would leave about 3.5 watts, while RG213 would leave about 4 watts, according to quick AI calculations. LMR400 is expensive and at this short distance, would be a negligible difference; for longer runs it would pay off. Just simply being above your and your neighbors roofs would make up for that loss. If your roof is metal, bonus ground plane! Or use a cookie sheet or similar. You can get a mag-mount that can take an SMA antenna so you use the same antennas you buy for your HTs for an inexpensive start, or go ahead and buy a mag-mount and antenna that can handle at least 50 watts for future base station set up. Attach BNC connectors to your HTs and the end of the cable for quick release, and Bob's your uncle!

I think as long as you get that antenna to roof height with a decent antenna and no more than around 15ft of coax, it would make up for the db loss.