City-Data Forum Ham radio question: Getting ready to take Tech exam and need HELP! (legal, fish)
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02-24-2011, 08:48 PM
 Location: Norfolk 1,574 posts, read 1,978,161 times Reputation: 5058

I'm an architectural historian. I write about old houses. A few months ago, I got a wild notion to get my tech license so I could play with Ham Radio. Now, it's 36 hours before the test and I'm starting to get CHICKEN!!!

Could some kind soul please explain - in simple terms that even a writer could understand -
the difference between current (I), volts (E) and watts (P)?

I have studied the water analogy, and I get that current is “flow” and volts is “water pressure” and resistance is the size of the pipe, but help me put all this together?

The meter on the side of my house measures watts, but how is that different from current? And volts?

Thanks for any and all help.

Sign me,
Cross-eyed Rose

02-24-2011, 09:27 PM
 Location: Planet Eaarth 8,957 posts, read 17,000,905 times Reputation: 7193
HowStuffWorks "What are amps, watts, volts and ohms?"

http://zone.ni.com/devzone/cda/tut/p/id/3037

National*Instruments

02-24-2011, 10:47 PM
 Location: Metromess 11,798 posts, read 21,344,716 times Reputation: 5054
Those are good links. At least the first two are. I need to download a new Flash Player to see the third one.

RosemaryT: Don't freak out! Just memorize the Ohm's Law formulas. I hope you pass the exam!

02-25-2011, 10:54 PM
 Location: Metromess 11,798 posts, read 21,344,716 times Reputation: 5054
RosemaryT: Please ignore the preceding post, or at least the part of it recommending that you become a bootlegger. The FCC is the part of the federal government which concerns itself only with the electromagnetic spectrum. You might be able to get away with illegal operating, but please don't. When someone looks up your callsign on an online site like qrz.com to get your address to mail a card or just to find out where you are, they'll find out that either you are using someone else's call or that it isn't in the FCC database as an active callsign.

02-25-2011, 11:03 PM
 7,788 posts, read 10,444,975 times Reputation: 3392

03-04-2011, 10:23 AM
 455 posts, read 1,328,225 times Reputation: 402
Quote:
 Originally Posted by catman RosemaryT: Please ignore the preceding post, or at least the part of it recommending that you become a bootlegger. The FCC is the part of the federal government which concerns itself only with the electromagnetic spectrum. You might be able to get away with illegal operating, but please don't. When someone looks up your callsign on an online site like qrz.com to get your address to mail a card or just to find out where you are, they'll find out that either you are using someone else's call or that it isn't in the FCC database as an active callsign.
I'm not so much into the ham scene, but I occasionally enjoy listening to scanner traffic. This may be a dumb question (not trying to offend any aficionados), but doesn't the government have bigger fish to fry... you know... like murders and corruption?

What's the point in regulating and licensing a mostly dead technology when the only people using it, for the most part, are hobbyists?

03-04-2011, 12:47 PM
 Location: Metromess 11,798 posts, read 21,344,716 times Reputation: 5054
You have an incorrect perception of ham radio. Far from being a "mostly dead technology", there are over 694,000 hams in the United States now, a new high. I am a member of the Radio Amateur Civil Emergency Service in my county and report severe weather along with many others. The local media and the National Weather Service depend on field reports from us. And many hams are experimenting with new digital modes.

The Federal Communications Commission deals with everything having to do with the allotment and usage of the electromagnetic spectrum, ham radio included. Other parts of the gov't deal with "murder and corruption". I'm not offended; you simply need to learn more about the many facets of amateur radio.

03-04-2011, 01:10 PM
 Location: Happy wherever I am - Florida now 3,359 posts, read 10,633,860 times Reputation: 3812
Watts (P) is the measurement of power that is produced by the combined forces of current flow (amps) and volt pressure (volts). Watts is a measurement of the energy produced.

P(watts) = Volts (pressure V) X Amps (current flow I)

She is studying for the test. I didn't see anything about illegal operation.

03-04-2011, 05:39 PM
 Location: Tyler, TX 15,194 posts, read 17,686,126 times Reputation: 7980
Just remember the PIE charts...

P = I * E
(Watts = Amperes * Volts)

I = P / E
(Amperes = Watts / Volts)

Etc...

03-05-2011, 11:41 AM
 Location: Norfolk 1,574 posts, read 1,978,161 times Reputation: 5058
Thanks!

Thanks so much for the interesting replies!

I passed my test, getting 33 out of 35 right and I'm the new happy owner of a "tech" license!

I'm not surprised that the number of Amateur Radio Operators is at an all-time high. Our society has become highly dependent on delicate electronic systems (cell phones and internet), and what would we do if we lost our cell phones or internet access?

I became a "ham" because I want to have access to alternate means of communication *if* the stuff hits the fan and/or if we have severe weather.

Being cut off during an emergency is tough enough, but being cut off with no means of communication is a glimpse of hell on earth.

Rose
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