BaoFeng UV-5R and similar for local

Started by kablooie, October 18, 2014, 04:11:41 PM

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kablooie

i am continuing to learn :) but now have a question re radios similar to the BaoFeng UV-5R. when my son and i get licensed and have radios similar to the UV-5R.......
what kind of range can i expect to have?
how does local communication (DX?) work?
is it radio waves going out and bouncing off the ionosphere kinda of thing?
what would lend to better reception / longer range with these radios of this size/caliber?
anything else to know about the above?

thanks!!!!!!!!!!!!!!!!
louie

gil

Quotewhat kind of range can i expect to have?

It depends on line of sight. If you consider two HTs with the antenna about 6ft. off the ground, then 2 to 5 miles, depending on obstacles. Climb on a roof and the range increases... I have been able to hit a repeater 30 miles away with my UV-5R, but their antenna was at more than a thousand feet.

Quotehow does local communication (DX?) work?

DX is not local, it means between different countries. Local communications can typically happen between two radios directly, called simplex, or via a repeater, which acts kind of like a cell phone tower. Without a repeater, expect a few miles range. With a repeater, probably up to 50-100 miles.

Quoteis it radio waves going out and bouncing off the ionosphere kinda of thing?

That only happens on HF, below 50mHz, and best at 14mHz and below. The UV-5R operates on VHF and UHF, so 144mHz and above. VHF and UHF are line-of-sight only frequencies.

Quotewhat would lend to better reception / longer range with these radios of this size/caliber?

A better antenna, and placed higher. Also, you can attach a 19" wire to the belt clip screw, that extends the range greatly. It's called a "rat tail." It basically is a counterpoise for your little rubber antenna.

VHF/UHF radios like the UV-5R are local communications radios only. If you want range, you need HF. Some radios do both, like the FT-817ND, etc. but are expensive. Antennas for HF are also very long, like 40-65ft. or more. Using a repeater increases the range of the UV-5R of course, but there must be one nearby. For HF, you need at least a General license.

About the UV-5R: The microphone jack is weak. Better not plug in an external mike or earpiece... You will need to plug in the programming cable if you want to use a PC for faster programming, but I wouldn't do that too often. Otherwise, it's a great radio. I carry one with me everywhere I go..

Gil.

cockpitbob

#2
Ditto on what Gil said.

The VHF and UHF radios are great because the antennas are 1/2 to 1.5 feet long instead of 15' to 260' for HF frequencies.  The bad news is the wavelength is so short the signals don't diffract back down from the ionosphere, but keep going out into space.  Hence, line of sight communication only.  The good news is all over the country hams have put repeaters on the tallest thing they can get permission for:  towers, tall buildings, etc.  So your antenna is likely to be able so "see" several repeater antennas that may be 10 to 30 miles away.  A repeater will retransmit your 5W signal with 50W or 100W from that high vantage point so hams 10 to 30 miles away can receive your signal.

To maximize your range from home, put an antenna on your roof, or in the attic like I did, and run good coax (RG8, LMR400, etc) down to your shack (desk).  With my UV-5R using my attic J-pole antenna I can hit and get strong signals from repeaters that I can't even hear standing on the ground using the rubber duck antenna.  In the car I put a mag-mount antenna on the roof and just slam its coax in the door(no mods to the car) and I can hit stations I'd have no chance of hitting using the rubber duck antenna inside the car.

A common theme in ham radio is that the antenna is more important than the radio.  I'll take a 100W radio and good antenna over a 1,000W radio and a crappy antenna.

Sailor

In easy terms, flat land expect 1-2 miles radio to to radio.

20-30 miles using a repeaters.


K7JLJ

With a slim Jim or Ed Fong antenna, I get up to 7 miles through the city at 10ft elevation of antenna.  YMMV

It's all about the antenna.
-Jim

gil

Hello,

For VHF, line of sight, it is just about that, line of sight... For two individuals about six feet tall, the curvature of the earth will prevent contact beyond five miles. 10ft. seven miles sounds about right. Power has little to do with range on the ground, except when obstacles clutter the line of sight, like buildings, vegetation, etc. For example, sailboats with their VHF antenna on top of the mast always have better range than power boats with lower antennas. Other phenomenons can come into play, like tropospheric ducting (https://en.wikipedia.org/wiki/Tropospheric_propagation), but generally, for HTs, antenna height is usually more important than power. Note however that the best way to extend the range of portables in a cluttered environment is a "rat tail," just a quarter-wave lenght of wire connected to the antenna ground at it's base. I usually get three more bars on the S-meter when using one. On the UV-5R, you can connect your 19" wire to one of the belt clip screws, which are connected to ground.

Gil.

emergen

I do have to add that VHF/UHF can at time get some significantly improved distances (not as good as HF though) through tropospheric ducting. If conditions are right its possible to communicate over distances of many hundreds of kilometres. Obviously chances improve with your elevation and the use of a quality antenna such as a j-pole or a yagi.

Using a HT with a j-pole or a yagi is also beneficial for improving line of sight comms as well.


Sent from my iPhone using Tapatalk

emergen

Sorry Gil I just noted that you've mention tropo yourself. My bad


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gil

Hello,

A J-Pole is nothing special, but a Yagi does offer a lot of gain. Of course any full size antenna will benefit a handheld, especially if it can be placed higher. If I was to build another VHF antenna now, I would make a quad, for compactness and gain, built of copper tubing. Regretably, you can't really find new all-mode VHF/UHF radios today that do not have HF included. I miss my Icon IC-271A; how dumb it was to sell it... I guess there is no market for them, too bad. You can find a lot on Ebay though by searching "All mode VHF."

Gil.