PMR446 Radio advice and troubleshooting
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Results for 446 and 449 external base antenna- dont waste your time and money on trying different antennas (like i did!) just buy a diamond ive got the x300n dual band and the v2000 tri band and they are the only ammature antenna that gives a swr below 1.5>1 and work VERY well!!
I made a 4 element Yagi for 446 up out of old bits and bobs in the shed, connected an off cut of rg58, powered up the Baofeng 5r and did some tests. Easy 10-15 mile range, and one copy (with ease) at around 25miles. Nothing fancy, no amps, aprrox 2watts output power (don't believe the manual). Total cost of bits and bobs probably came in at two quid. I'm not a radio genius, I just googled the instructions and followed them to the letter. Radio as a hobby need not cost hundreds of Â£Â£Â£s, with a little thought.
Just a little update, I've now modded my yagi slightly, attached my Baofeng 3r to it and tuned it into satellite frequencies, it performs very well. Total cost, around Â£40. Now I need to make another portable antenna system with reasonable gain to replace that yagi, I've botched together a bowtie antenna, run it through the Baofeng at head height on low power (1watt) and achieved a readable contact at ten miles to a mobile unit. The gain of the bowtie is around 8db (d, I think) and very directional. I've run out of antenna building odds and ends for now, so experiments have drawn to a close.
Ok, upped the game a bit. Made another Yagi up, 7ele, and it blasts out. I couldn't test SWR on any of the antennas I'd made until tonight, so it was always fingers crossed when I used them. I checked SWR on them tonight, 4 ele was 2.5, so I've trimmed that down and got it at 1.5 now, the 7ele was straight in at 1.2:1 so happy days. I'd also made a little dipole up as a monitoring antenna, so I checked that as well, bang on 1.2:1 as well. Now I'm not sure what I've done right, I've been told the best I should be able to expect on an antenna with a dipole in is 2:1, yet all mine have come in far better, certainly luck, not skill or judgement!! I did take all the measurements specifically for 446mhz, but they return typically around 2:1 on 70cms.