27-07-2018, 05:44 PM
(27-07-2018, 04:37 PM)VK5PJ Wrote: Hi Wayne
you also need to consider power levels in your planning. the vk3um EMR calc software is very handy for visualising the situation. I used this as a planning aid for a VHF high power permit application some years ago and learnt quite a bit from it during the process. I say this about power because an antenna is only a threat once it is enegised and the level of threat is dependant on the power level being used. I know most of the 1KW HP trial permit holders failed on EMR because parts of antennas were to 'exposed' to human contact. What that actually was I am unsure but using the VK3UM software you can see what exclusion zone it gives you for an antenna / power level combination and not rely on us bush laywers in forums :-)
Peter, vk5pj
Hi PJ
Yep, done that for every band between 1.8m and 23cm and for every antenna I use. I never run more than 100w on HF and much less or VHF/UHF so all except 23 cm came up with "ACMA level 2 compliance not required" but me being me, I did the calculations anyway. The exclusion zone on the vertical came out at about 3m (my gated back yard is more than 3mSq) and the inverted Vee which is 8m high in the centre was less than 1m.
It's this "antenna must not be touchable" ruling by the RI's" that has got me a bit confused.
Wayne VK4WDM