Baz JJ Posted September 3, 2013 Share Posted September 3, 2013 deleted Link to comment Share on other sites More sharing options...
Moose87 Posted September 3, 2013 Share Posted September 3, 2013 you miss understand what im saying, you are completely right. the actual wave is fixed but what i was trying to get across is that at 30mhz a wave length is 10m but if you build a 7.5m antenna it will only transmit 3/4s of the wave length. my original point of thinking is that if you cant up the power than you could try increasing the size of the antenna and therefore more of the wavelength will be transmitted Link to comment Share on other sites More sharing options...
Baz JJ Posted September 3, 2013 Share Posted September 3, 2013 Yes. At 446 Mhz, the wavelength is about 67cm. All PMR446 radios come with a little stubby antenna which has an electrical length much less than 67cm. If you could increase the antenna length, then you would improve its antenna gain/efficiency and therefore its effective range. That is why they do not permit this to happen. It is also why PMR446 is pretty rubbish in terms of range. Link to comment Share on other sites More sharing options...
Supporters jcheeseright Posted September 3, 2013 Supporters Share Posted September 3, 2013 most decent quality handheld radios allow for you to put a bigger antenna on them though, it's completely legal as long as you're not transmitting at greater than 0.5W. in real terms a bigger (or I should say more appropriately sized) antenna will help far more with reception than transmission. Link to comment Share on other sites More sharing options...
Baz JJ Posted September 3, 2013 Share Posted September 3, 2013 Initially OFCOM tried to insist on an integrated antenna so it couldn't be modded. I think that has now been relaxed. Many cheaper sets on the market still have the integral antenna. At 500mW output power, I don't think you will notice much of a range difference between the stubby and the largest whip or helical antenna you can fit and still maintain portability for Airsoft use. Link to comment Share on other sites More sharing options...
Supporters jcheeseright Posted September 3, 2013 Supporters Share Posted September 3, 2013 well no, but with a longer antenna you'll be able to RECEIVE signals from further away. if both parties have longer antennas then you're getting increased 2 way range. Link to comment Share on other sites More sharing options...
Supporters Ian_Gere Posted September 4, 2013 Supporters Share Posted September 4, 2013 While we're on the subject of modding handsets, can you get better reception via the black magic of earthing some part of the circuitry or case? I vaguely remember the CB craze back in the day and people did use to do some odd things... Obviously "earth" and "portable" are usually mutually exclusive, but we're not talking about much in the way of voltage and even less current, so the human body would act as an earth. Link to comment Share on other sites More sharing options...
Baz JJ Posted September 4, 2013 Share Posted September 4, 2013 No because they work on a balanced output. CBs didnt. military field radios sometimes need an earth especially on HF frequencies which need a longer aerial due to the lower frequency. Link to comment Share on other sites More sharing options...
Moose87 Posted September 4, 2013 Share Posted September 4, 2013 Ah HF radios are my fav. You can build some of the most random antennas for them. I remember one we managed to pick up something in eastern europe crazy. Link to comment Share on other sites More sharing options...
chris555 Posted September 5, 2013 Share Posted September 5, 2013 If anyone feels confident on fabbing a new areal on a midlands g7 plwease post how to do this Link to comment Share on other sites More sharing options...
Baz JJ Posted September 5, 2013 Share Posted September 5, 2013 I dont think the aerials on the G7 come off. Looks like they are the integrated type mentioned earlier in the thread. I have similar on my Motorolas. Link to comment Share on other sites More sharing options...
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