That was with 200mW and a helical the size of SENTRY's manhood, so that has to be the mother of all helicals ...Originally Posted by Trappy
That was with 200mW and a helical the size of SENTRY's manhood, so that has to be the mother of all helicals ...
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Oh, and that was our very own Kiwi taking residence in Germany flying out to 8km, he goes by the nick whakahere (I might have missed a w, a, h or k somewhere, sorry!).
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Same for "rabe2000", he used also 200mW and a CL/helix combo to reach 8km.
so ... in theory to double the range you need 4x the output power. in that sense, 25mw * 4 * 2 = 200mW, which would reduce our range to approx 8 / (2 * 1.5) = 2.6km. What gain was the Helix at? It seems CL / Helix is the way to go ...
Edit: Ok, so we did the math assuming pretty good receiver (-90dbm) and values that we use to calculate our 2.4GHz range and assuming a 1.25dbi TX (CL) and a 12.5 dbi Helical. We get nowhere near that range (in theory). So something definitely smells fishy ... I'm assuming both CL and Helicals used were much higher gain, and the 200mW Tx is actually spitting out a little more than 200mWcould whakahere maybe chip in and let us know some more details? that would be cool
Last edited by Trappy; 12th November 2011 at 05:51 PM.
oh, well, 27dbi 5.8 grid on order. poor RiSCyD, he's gonna need to track this beauty manuallyanyone got a good source for 5.8 tx whip antennas besides the CL?
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I hit 8km with a 8 turn helical and a tuned CL. But that was on 200mw. The picture was great the way through and I even set it down 3km away (ran out of battery on the return.) As of right now with all the low cloud range the range is less. Narrow beam on 8 turns so it does require tweaking the antenna in flight. I have a few more helicals that I have built that I want to test out but the weather is really low fog rubbish.
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whakahere, what does a 8 turn helical translate into in terms of dbi? are you sure you are using 200mW? what kind of modules are those? sounds like that helical is seriously high gain and the TX produces more output than advertised
oops... sorry guys, my 5.8GHz experience was all at 600mW. Totally off topic for 25mW.
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