Best antenna for PMR446 and circa 499mhz UHF

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Best antenna for PMR446 and circa 499mhz UHF

Postby rich83 » Fri Mar 13, 2015 11:33 am

Hi guys. I go to woodland events where the organiser has licence for us to use high power on frequencies circa 499mhz and we use Baofeng radios.

The question I have is what is the best antenna for this frequency, and would it work on PMR446? Of course I wouldn't ordinarily use it on 446, but I always take a walkie talkie when I go hiking or wild camping with my son incase we get into difficulties so that we can broadcast an SOS in the hope somone will hear us. Wife always knows where we are going and when to come looking, but taking precautions never hurts so I take the radio.

What then:

IS the best antenna for UHF 499mhz on the Baofeng (UV5 and UV8)
IS the best antenna for UHF PMR446mhz on the Baofeng (UV5 and UV8)
OR will one good antenna cover both as they are close?

Cheers ladies and gents. If this has been asked, then I apologise. I did use the search function but I am not techinal so can't make my own and didn't quite understand the CM length importance!!
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby thelad » Fri Mar 13, 2015 12:49 pm

Do you mean 449 mhz?
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby m0lsx » Fri Mar 13, 2015 1:34 pm

thelad wrote:Do you mean 449 mhz?


There are a couple of 449 frequencies on PMR simple. But as for an antenna I have never seen any antenna designed for this frequency & without seeing a 70cm antenna on a antenna analyser at 449 I would not like to say if they work very well or not.
I know some 70cm antennas do work at 446 even if the SWR is starting to get a little high, but due to the alledged gain at 70cm on some of these handheld antennas, I would expect a highish Q & thus a sharp & narrowish band.
I do know that many of the longer 70cm handheld antennas are best not used on 446 TX, as I have seen someone put some on a analyser & only one antenna out of 4 or 5 had a SWR below 3:1 & that was just over 2:1.
On RX any handheld antenna is good, but not on TX.
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby radiospy » Mon Apr 27, 2015 2:21 pm

how can the baofeng-uv5r antenna that we got with it work 136-174 400-520
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby m0lsx » Mon Apr 27, 2015 2:54 pm

It is a compromise antenna, on a compromise radio.
It is simple to build an antenna with a wide band of very low SWR, as SWR is only one of the factors to take into account with antennas. And having a low SWR does not mean that the antenna is a good one to use, far from it.
If you look on CB forums they will tell you that a 9 foot whip is a good antenna for 27mhz..And it is if you only look at SWR. But if you look beyond that you will find a 9 foot whip has a massive performance reduction created by something called Radiation Resistance (rr.) And thus it has less performance than an antenna with a high SWR.
I use to use a light bulb on HF as my dummy load of choice & have I have an old Golden Syrup tin some where with some resistors & oil in it, that gives a very nice broad band of low SWR.
You will find with the Baofeng that on frequencies away from it's band centres that it is not very good on power out or a few other things, so an antenna that is not 100% is not a big issue any how.
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby rich83 » Sat Apr 09, 2016 7:02 pm

Hello guys I am again searching the web for a better antenna - this is where I started and to be honest I didn't get very far.

I think most people agree that the standard Baofeng antennas are naff so I ask you, for UHF TX/RX which antenna would be an improvement?

As I said previously, we use 449 mhz so the antenna would be used for the following RX/TX

See here for actual freq's - http://s24.postimg.org/jp6fcg5w5/Capture.jpg

In addition, it would be useful (but not especially necessary) for it to also work in the PMR 446 frequencies/channels for emergency use. The woodland environment where we use these radios is massive, and in the event of an emergency I can see that it would be useful to TX at a longer than potentially legal power in the even that I end up breaking my leg and am on my own... A friend did this and was lucky that he was found a few hours later by dog walkers but as I am carrying a radio I figure why wait?*

Anyhow guys I appreciate your help in this matter. If for no other reason that I could be safe in the knowledge that my thirteen year old son could have a programmed emergency channel (like CH1 on 446) in the event he gets lost or separated.

I don't intend to break any laws - we use the licensed 449 as described in the image, taken from Chirp but I would like to get the best TX and RX from my radio so I set the TX power to high but I imagine a better antenna would be an improvement.

*446 on anything over .5w is unlawful, I know this but I'll happily pay the fine/take the punishment if it saves me or my boy any undue distress.
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby thelad » Sat Apr 09, 2016 8:28 pm

Best using the VHF freqs for use in woodland.
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby m0lsx » Sat Apr 09, 2016 9:31 pm

rich83 wrote: *446 on anything over .5w is unlawful, I know this but I'll happily pay the fine/take the punishment if it saves me or my boy any undue distress.


Your use of the radio goes beyond just using more than 0.5 watts. Your antenna is not legal as it is removable & your radio is not approved for use on 446 & you hold no licence that you have mentioned.
Section 26 of the 2006 Wireless Telegraphy Act covers possession of radio equipment for unlicensed or unauthorised use. And section 8 covers installing or using radio equipment outside the terms of the licence or exemption. You are in breech of both sections & just so that you know. Each breech of the Wireless Telegraphy Act carries a maximum penalty of up to £5000 plus 2 years in prison. On 446 that means nothing as I cannot ever think of anyone who has ever been prosecuted. But use away from that & there could be a penalties to pay. Big ones.
If the ownership of the radio is legal you could get away with miss using a radio in an emergency. HOWEVER, as you have no legal right to own or use that radio (unless you have a licence you have not mentioned) that discretion to use in an emergency would not be possible in your case.
As thelad says UHF would be very poor in wooded areas & my personal experience with UHF, is that it would be poor between handhelds in most other locations too.
The expected range on 446 even at 5 watts with a half reasonable antenna is going to be little further than your voice covers under most circumstances & certainly much less than a good whistle would cover.
Sitting high on the side of a hill or mountain the coverage of the valley below may be fair. But it only takes a hedge to obstruct the path & that signal will disappear.
There is a good reason why rescue organisations recommend a whistle & not a 446 radio & that is in most terrains UHF range is heavily attenuated. Whilst whistles have no batteries to go flat & get attention from everyone who is not deaf, especially when used properly. Whilst a radio only works if someone is within range & has a radio on your frequency that is switched on.
Lets be honest, anyone who thinks for more than a millisecond about the claims. "I only own an illegal radio as a piece of emergency equipment. Just in case." Realises after few milliseconds that it's an excuse & not a good one.
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby Chris P » Sun Apr 10, 2016 7:14 am

whilst the organisers of the woodland events you describe may have a business light licence for 449Mhz, unless they supplied the radios for you to operate on their behalf and authorise you to use them you also need to have a business light licence to operate if the radios are yours . I believe there is a case for any frequency to be used in a Risk to Life situation but as Alan states you need people monitoring those frequencies at all times for any such transmission to be of any use .

I totally agree with Alan with regards to the range of UHF in wooded areas and agree with thelads comment that the business light VHF frequencies would give better range in those circumstances
Regards Chris aka G8FFF nipper or tazmin88
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Re: Best antenna for PMR446 and circa 499mhz UHF

Postby G4RMT » Sun Apr 10, 2016 10:38 am

I really am quite surprised by the constant complaints about the Boafengs. Performance wise, none of the models I have for demo purposes perform badly enough that I can label them 'trouble'. There are many models, and sure, some have some silly features - all are sensitive enough to offer decent communications. Some are too flimsy, but in some environments, where you need disposable radios, these are fine. Woodland events, in my own opinion would be ideal for these value for money radios. They can get dropped in muddy puddles, perhaps even totally lost when they fall out of pockets, so it's no big deal. They do fall down when used in locations with strong local signals on the next channel, as the filtering is less than ideal, but in the woodlands?

When I run events or hire kit out I usually label the radios with the callsigns, and I have no issues with somebody wanting to use his own radio - I happily give him the frequency and tone, and allocate him a callsign. The suppliers license has no ownership rules, only the technical ones. Legally, his radio just becomes covered by my license, with me as the responsible person. Higher power - which really means what? 2-3W or more from a handheld.

I have three categories of hand-held radio aerials, in my head, and only two in stock. Shorter than ¼ wave, or ¼ wave only on UHF. I don't use aerials with gain because they're simply too big - and in woodland, just impractical. When I do jobs in tricky areas that are quite big, it's easier to get a vehicle into the centre, with a repeater and a short pole. If you can't get a vehicle in there, then a case with the repeater and a leisure battery to power the system work well. A ¼ wave for UHF, and the same kind of length helical for VHF is my limit.
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