GPS with RTK like farmers use is quite accurate taking out the
variability of short term propagation and the randomness built into the
GPS system. Raw GPS varies the position while still and changes it more
when passing under bridges and around buildings. And a workable GPS runs
$80 and up and a digital stop watch can be had for $10. RTK uses a fixed
station that transmits the GPS data it receives so the mobile GPS can
correct for those vagaries. More expensive GPS can make use of some
public versions of those used for ship and aircraft navigation. I think
without those you will see s few mph more variation than your potential
speedometer error and more variation than your driving speed.
73, Jerry, K0CQ
On 4/1/2011 8:23 PM, Greg S wrote:
Jerry- as to "most easily accomplished" for checking a speedometer, I
gotta believe a GPS is more accurate, and a HECK of a lot easier,
isn't it??.......
and, Mike- I have a solution to your frets about output power: Sell
your calibrated equipment, and run her by the seat of your pants....
if you make the contact, you have enough power, if you don't make it,
give her a bit more "foot feed" until you either make it, or run out
of "pedal". I find it funny how we all have our own little quirks
about things that bother us: I.E., I had an Omni VI, and sold it for
2 reasons: Narrow recieve audio on SSB (SOMETIMES a blessing), and
the straw that broke THIS camel's back was the drift at turn-on. Both
"issues" with the rig were amplified (no pun intended) by the Kenmore
TS-850 that I had along side it, which had neither issue, (Can you
say polar opposite on receive audio??) and was about the same age. I
decided to sell my Telewave meters, and have a cheap CB type meter in
line that shows relative forward and reverse power at the same time.
Am I running 35 watts, or 70 watts out of my Corsair II??? I don't
know.... nor do I care. Hope it helps ease the sting a little. (I
couldn't take the sting of it- I sold the Omni VI. I had it alongside
the Kenmore for around a year, and NEVER, under any condition, was I
able to copy a station on one rig, and not the other.)
73- Greg Schippers, KC8HXO
"Those who would give up essential liberty to purchase a little
temporary safety deserve neither liberty nor safety." - Benjamin
Franklin
--- On Fri, 4/1/11, Dr. Gerald N. Johnson<geraldj@weather.net>
wrote:
From: Dr. Gerald N. Johnson<geraldj@weather.net> Subject: Re:
[TenTec] eagle To: tentec@contesting.com Date: Friday, April 1,
2011, 8:42 PM --------------------snipped------------------------ A
dynamometer won't necessarily show that your car speedometer is
wrong, that's most easily accomplished on a road with measured
markers at 1/4 or 1 mile intervals and a stop watch.
------------------------------snipped--------------------------
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