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[aprssig] Re: New Exam Question Pool

Jim Lux jimlux at earthlink.net
Sat Mar 11 19:16:31 UTC 2006


This is a fine example of an extremely poorly written question.  Let's look 
at it more detail:

What item is required along with your normal radio for sending
automatic location reports?

OK.. "item" is singular, and the way the the question is worded it implies 
that you need only that one item to add to the normal radio.

What's "normal radio"?  most radios these days don't include a digital 
modem (for the Bell 202 tones), nor any processing to do the link level 
protocol (HDLC and X.25), nor the application protocol (APRS).  Sure, there 
are a few (<5) models commmercially sold that include some or all of this, 
but the vast majority of radios out there (after all, the question doesn't 
say VHF/UHF FM radios, so it includes all those HF rigs)

I'd say that the correct answer is more like "a computer with a GPS and modem"

If you allow the poor wording to mean "what of the following could be used 
with a radio and other equipment to send automatic position reports", any 
of the answers would work.  Sailors used speed and compass heading for 
centuries to establish position.  And, of course, time stations like WWV 
(and the BBC) made longitude determination much simpler.  The Broadcast FM 
subcarrier receiver is a bit more of a reach, but for many years, GPS 
differential corrections were broadcast on FM subcarriers, so a suitable 
subcarrier receiver was an essential part of a precision GPS setup.

And, of course, if you had a voice parrot in your car that you loaded with 
the interstate number and exit you were at, that was set up to squawk every 
minute, it would be automatic reporting of position.

All in all, not a very well worded question, nor answers.

Jim






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