Tom
The reason we expect a level of accuracy is that it has been made available
to us in modern equipment. You are right in saying that many of us don't
understand accuracy requirements. The only requirement that concerns the FCC
is accuracy at band edges. All modern ham gear is well within this spec.
Ron
K3MIY
-----Original Message-----
From: tentec-bounces@contesting.com
[mailto:tentec-bounces@contesting.com]On Behalf Of Alderman, Chester
Sent: Tuesday, March 04, 2003 11:10 AM
To: 'tentec@contesting.com'
Subject: RE: [TenTec] Argonaut V ARRL Review 3rd and 2nd IPs ?
"You can't measure a signal to
millivolt accuracy if your test instruments are +- .1 volt in accuracy."
I think this is a GREAT point for all of us hams to understand!
There is now a discussion ongoing about the frequency readout to 1Hz, but
most of us don't yet grasp the concept that we are buying and using amateur
radio equipment and NOT a precise frequency counter. Really precise
frequency counters, power meters, test equipment are calibrated to standards
traceable to NBS, on a quarterly requirement. Amateur radio equipment are
not, and are not required to be, calibrated to ANY standard.
Why do we expect our ham gear to be within 1Hz accuracy or within
.001 watt accuracy?
An accurate power meter, for instance, cost around $4000. Then it's
accuracy is only guaranteed if it's calibrated quarterly to a NBS traceable
standard.
We hams test our amateur gear by EAR! And we have no real need to be
concerned about +/- 1Hz or +/- .1 watt.
Tom/W4BQF
-----Original Message-----
From: KD5NWA [mailto:KD5NWA@cbayona.com]
Unfortunately just because you use the same method, doesn't mean the
results are any good. For example if the testing methods because of using
different mixing methods generates it's own IM into the picture, it will
greatly affect the results. A radio with lousy IM distortion, will show up
bad, but a radio that has great specs, will suffer terribly, making the
user think that the better radio is really not that much better, when the
truth is that there is a huge difference. You can't measure a signal to
millivolt accuracy if your test instruments are +- .1 volt in accuracy.
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