Mayhem on AmRad 40 m. band

[Yorkie]

Re your skills as a chainsaw operator, as you of course well know, they go far beyond mere knowledge and experience and include considerable manual dexterity and an overriding need to be safety conscious at all times, working at heights, handling timber often weighing tons. You can - and people do - kill themselves (even professionals) with chainsaw accidents - you can't by pressing a PTT on a mike! I hope that doesn't sound too pedantic or perverse.

As to RF power, n terms of the received strength of an RF signal, it isn’t directly proportional to the transmitted power in Watts. EG:

1 Watt = 30 dBm (0 dBw)
10 Watts = 40 dBm (10 dBw)
100 Watts = 50 dBm (20dBw)
1000 Watts = 100 dBm (30dBw)

That assumes no transmission losses, which inevitably arise between the transmitter and antenna, especially in amateur radio stations. Radio amateurs seem to think that if they use an ATU to reduce the standing wave ratio to 1:1 that all the power from their transmitter goes to the feed point of the antenna.

Complicated business, which I profess no deep knowledge of myself, and have no particular interest in as the maths makes my eyes glaze over:

http://en.wikipedia.org/wiki/DBm

http://www.rf-amplifiers.com/index.php?topic=rf_power

http://www.evaluationengineering.com/art...ineers.php

I don’t think the average radio amateur – DX chaser or not, trouble themselves with these niceties – they just string together shop bought stuff and away they go. They’re hobbyists after all – few these days are professional RF engineers. Remember that the training and assessment for an amateur radio licence is pitched at the lowest possible level to minimise or obviate risks to other spectrum users, notably the emergency services and Air Traffic Control. The restrictions that public bodies such as regulators (Ofcom etc), place upon any of us must be based on the principle of proportionality and can go no further than that.

I support the licence structure, but it is not – as many imagine - a training course to enable radio amateurs to become competent at understanding RF engineering – it’s for the reasons stated. Some may want to read up beyond that – most (in my experience), do not. So long as they’re having fun, it’s of no great importance.

The RAE is a very elementary qualification which is why the C&G dropped it. We are constantly being regaled by the likes of RSGB with pictures of bright eight year old kids who have passed the foundation licence – the only test that is mandatory – the other two bolt onto that).