Sunday, December 14, 2014

Got Those "Term Paper" Blues......

Well, not exactly a "Term Paper", but it makes me glad I wrote all of them in high-school and College.

I've been asked to do a short report on RF Safety, and how it pertains to the Amateur Radio operations aboard the Iowa.

Actually, I was asked to do a full report, and oh, by the way, can you have a short one available for our meeting this Wednesday?

Now, all the Hams I know are quite conversant on RF Safety, and we've all performed our FCC mandated RF Evaluations of our stations.

I don't know a single Ham who has not done this, and nobody I know has a station that doesn't meet the requirements.

The "problem" arises when you say "RADIATION" around most lay people, who don't know the difference between an X-ray, cosmic ray, a sun ray, or even a "Ray of Hope". All you have to do is mention "RADIATION", and people start thinking of giant ants, giant grasshoppers, or Big Things We Accidentally Created/Let Loose/Got Pissed Off.

Since Radio Frequency radiation is NON-Ionizing, it's extremely unlikely to cause gigantic tomatoes and bugs to start appearing under your antenna. It just doesn't work that way.

The primary harm the high levels of RF can cause, are thermal hazards, similar to sticking something into your microwave oven and cranking it up.

And even that has requirements to be met before the object will heat up.

It's true that in the "Olde Days" Diathermy used a frequency in the vicinity of 30 MHz, but the patient was positioned in almost direct contact with the antenna, and the antenna was designed to concentrate the RF field into a very small area.

They weren't having people stand under a half-wave dipole and applying 100 Watts to it.

So, I'm writing this with the LCD principle, trying to make it simple so non-technical people can understand it, while keeping it technically accurate, and not boring the people that actually understand it.

I just hope it doesn't get picked apart by the people who are "just too busy" to take this task on themselves, but yet not so busy that can find the time to read it, and nit-pick it to death.....

4 comments:

  1. Hmm ..... say "radio waves", rather than "radiation". Perhaps the hoi polloi won't wet themselves, since everyone knows radio waves are harmless ... harrumph.

    Remember back in the good ol' days when people still had some education? That era's gone, apparently.

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    1. Naw, the genie's already out of the bottle, and we can't get him to go back in!

      And yep, I still wish more people had a better education in basic Science.

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  2. Dang it, I wish I could find the video. This reminded me of a mention, I think it was Roberta X, about a guy using a shovel to tap into stray RF on a broadcast antenna. I think it was even on one of the guy cables. Anyways you could hear the content, and the arcing to the shovel ate away the metal.

    Good reminder to revisit that section of the license manual.

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    Replies
    1. I've seen things like that in Real Time.

      One trick was to take a good old #2 "lead" pencil, and use it to draw an arc from the tank circuit of a high-power transmitter. The graphite in the pencil gave you a high resistance for current limiting, and if you were running a few hundred Watts, you could get quite an impressive display.

      Back in high-school when I had my station set up for a science fair demonstration, I had one of my friends walk around by the antenna with a 48" fluorescent tube.

      People were amazed that the tube would light up with being connected to anything.

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Keep it civil, please....