John Galbreath 2021/08/24 11:12
Forgot to ask you - what is the velocity factor of the HP 85051 Beatty Standard ?
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John Galbreath 2021/08/24 13:12
On second thought, VF must be 1.0 since the dielectric is air. This is one reason to avoid public post - every one knows how stupid I am.
Jim Lux 2021/08/24 13:23
On 8/24/21 1:12 PM, John Galbreath via groups.io wrote:
> On second thought, VF must be 1.0 since the dielectric is air. This is
> one reason to avoid public post - every one knows how stupid I am.
> _._,_._,_
We specialize in gnat's eyelashes here - What is the air pressure,
temperature, and humidity? Or are you running in a vacuum.
And, of course, you should take into account general relativity - what's
the gravitational field like at your measurement station - it affects
the apparent speed of light.
(the funny thing is that I know people who DO obsess about such things -
but they're worried about 1 part in 1E12 kind of measurements - at those
scales, you can easily see the AC cycling on and off)
Joe Smith 2021/08/24 15:37
>> On second thought, VF must be 1.0 since the dielectric is air. This is one reason to avoid public post - every one knows how stupid I am.
Normally I would suggest contacting the manufacture for questions about specific products. You will avoid a lot of internet noise this way. For my hobby, I really have no use for any sort of metrology grade parts. If I showed you my homemade airline Beatty standard, you would laugh.
Jim Lux 2021/08/24 16:40
On 8/24/21 3:37 PM, Joe Smith via groups.io wrote:
> >> On second thought, VF must be 1.0 since the dielectric is air.
> This is one reason to avoid public post - every one knows how stupid I am.
>
> Normally I would suggest contacting the manufacture for questions
> about specific products. You will avoid a lot of internet noise this
> way. For my hobby, I really have no use for any sort of metrology
> grade parts. If I showed you my homemade airline Beatty standard,
> you would laugh.
> _._,_._,_
You *think* you have no need for metrology grade parts. And then the
addiction creeps in. First, you get a decent OCXO for frequency
accuracy and phase noise. Then, you discipline it to GPS, because,
after all why not. Then you need three of them (because the person with
two clocks doesn't know what time it is). Repeat for voltage measurement
or any other measurement.
Yeah, probably not going to make you the life of the party (except in
some specialized circumstances), but isn't a ppm better than 0.1%? and
isn't a ppb better than a ppm?
And then you can experiment with archaic methods of measurement. All
these computers, but isn't a slotted line really how it should be done?
it's all about the journey, not the destination, isn't it.
Lou W7HV 2021/08/25 05:06
On Tue, Aug 24, 2021 at 05:40 PM, Jim Lux wrote:
>
> ...it's all about the journey, not the destination, isn't it.
With hobbies, we usually can exercise greater choice over the journeys we choose to take.
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