There are low pass filters and there are low pass filters. A first order filter would at best filter the 2nd harmonic by 6 dB. If your output frequency is relatively constant, the proper way to do it is to use a highly resonant band pass filter.

And yet other gun owners in this discussion are claiming this is a good thing, because now the criminals know to avoid them. The spite and fear is because too many people buy guns because of some glorious fantasy.

Irrational attraction to lethality (e.g. all this "tactical" bullshit) should also be considered a mental illness.

Put the bloody things in gun safes, like you do in Australia! It's not totally secure, but carrying a safe out is an obstacle, and it's also pretty good at reducing stupid accidental shootings from people (including kids) screwing around with loose guns. Yes, it's bad for defending your home, but for some reason that just doesn't seem to be much of an issue in much of the world.

Loudness is unrelated to the amplitude of the carrier signal that's being frequency shifted. Hence the FM rather than AM. Besides, since when do radio stations have competing signals on the same frequency (do you know what capture effect is)?

Oops, I meant:
"...but disagree that knowing how the work is any more important than basic physics and "how stuff works" knowledge of everyday items."

I agree that knowing *how to use* computers is very important to daily life, but disagree that that is any more important than basic physics and "how stuff works" knowledge of everyday items. You rarely *need* to know how things work, but it's nice to not have the wool pulled over your eyes and be able to make useful logical deductions. I like knowing how computers work, but I wouldn't elevate them over fields.

Your toastmaster suggestion horrifies me :o

Is it possible that you don't realise how many marvelous things you have no idea about and don't care about (it would be ironic given the topic :D)? A lot of my friends are CS or SE graduates and don't have the faintest clue about things I think are common knowledge and important (I'm a mechanically inclined aeronautical engineer).

There are multiple effects. I'm aware of lower frequencies passing through obstructions easier, but that's not the f^2 effect the poster mentioned.

Yep, thanks. I found that article after I wrote that post. So it's an antenna effective area effect. Didn't know that. :o I also found that in urban environments, the effect of distance is much stronger than inverse square, making the antenna area a smaller component of range limits.

Just quickly though, it seems that tastesicle's 30 inches for 60 GHz is incorrect. With 4 times the power of 5.4 GHz 802.11 and 60 GHz, I get 12 feet not 30 inches.

I have never heard of this frequency vs range thingamajig. Unless you're referring to losses through solid objects. Satellite TV would not exist if this were true. 240 W, 12 GHz, 36,000 km distance and only ~30 dB receive antennas.

Please provide a reference to this "101" level effect.

Interesting. Perhaps it's more affordable in Australia (that's a first!), because the people I know of aren't rich, just a little obsessive ;)

I've been to factory equipment auctions and browsed online and you can get some really cheap used 3 phase machinery; as soon as something 1 phase shows up the price rockets. Businesses seem uninterested in the old equipment, but guys tinkering in their sheds love them.

AFAIK 20 A at 240 V is the most you can get from single phase in Aus, with 10 A at 240 V being a standard power point, so 3 phase is not so uncommon (even small food shops have it). Remember that it's not just a matter of high power, but dumb motors run nicer off 3 phase.

Oh bullshit. I know of numerous hobbyists who get 3 phase installed on their properties so that they can use used machinery like welders, lathes and mills. They don't even need to be particularly powerful devices, unless 2 kW is your definition of large, because industrial equipment tends to use 3 phase by default. Unless all you're saying is that no residence comes with 3 phase by default, in which case I agree.

I don't suppose you've ever worn a heart rate monitor during a weight lifting session. Recovering from anaerobic effort is an aerobic process (for some reason this escapes most people), and believe me, when you're lifting heavy you pant and beat hard afterwards. The times I've worn my HRM, my average HR was around 135 140 (about the same as fast walking?), peaking at 183 after deadlifts. And don't think that my rates are high because I'm unfit; when I do 10 mile time trials on my bike my average HR is ~170 over 26 minutes (37 km/h average speed). I'm not saying it's equivalent to any other cardio, but to say that lifting does not exercise the CV system is a load of BS. Admittedly, the effect would be reduced if you trained with 1 or 2 rep sets and very long breaks in between.