I was inspired recently coming across a Lampkin 105 frequency meter, as to
how frequency measurement was done before counters.
Certainly zero-beating a dial calibrated oscillator, would be one approach.
Is there a standout methodology or instrument predating counters?
___
Hi
Using ADEV as an example (the other stuff will have it’s own curves, but the
result is the same):
A typical Rb should have a stability at short tau that goes as 1/ square
root(Tau). If you are at 2x10^-11 at 1 second, you
will be at 2x10^-12 at 100 seconds and 2x10^-13 at 1,000 seconds. Som
On 2/11/17 10:22 AM, Poul-Henning Kamp wrote:
In message <589f4a79.3050...@rogers.com>, MLewis writes:
Late yesterday I placed old neoprene rubber mouse pads, rubber side
outwards, up the metal blinds between the blinds and the antenna.
I can guarantee you that it is not the neoprene
Hi
For any microwave material, the good old “toss it in a microwave” test is a
quick
and dirty one. If the material heats up, it’s lossy. Yes, there are other
fairly exciting
things that can happen other than it warming a bit ….
Bob
> On Feb 11, 2017, at 5:51 PM, MLewis wrote:
>
> Interest
In message <344e0d5f-e79f-fcfa-eba5-4cf50e047...@comcast.net>, Peter Reilley
writes:
>If a solar farm also included a battery bank then they would be able to supply
>VAs along with Watts just like a conventional generator.
The large MW size solar farms can already do that but with capac
Interesting.
My guess wasn't a material made for RF but a carbon added to give a
decent black colour.
"It is not inconceiveable that off-spec or scrap materials from the
production might end up as mousemats." and "stealth material".
Very interesting.
At an airshow many years ago, these mouse
Thanks Bob,
I should clarify the MTIE measurement extends 10 seconds (the others are
less time). Is it a reasonable question to ask if GPS is needed? Or are there
other variables that are involved?
Good point about the temperature stability, I hadn't considered that. Can I
place in a tem
In message <006a1c6a-0b2f-16fd-5fef-64352ff14...@earthlink.net>, jimlux writes:
>On 2/9/17 4:03 PM, Poul-Henning Kamp wrote:
>>
>> In message <63beea7a-f9fc-6e1d-b855-2c7056de3...@earthlink.net>, jimlux
>> writes:
>>
>>> I think also of the issues from distributed generation - co
They may well be willing to pay for more expensive equipment because they
can make money from it. large industrial electricity users pay for the VAs
that they use. Even though they are not energy the utility has to
supply them.
The utility charges for this service.
If a solar farm also incl
One issue with power factor corrected power supplies is that in the short
term (as a minimum, at the line frequency), they do behave like resistors
(current goes up when voltage goes up) but as they have a slow voltage
regulation loop to provide regulated output, they do behave like constant
power
In message <589f4a79.3050...@rogers.com>, MLewis writes:
>Late yesterday I placed old neoprene rubber mouse pads, rubber side
>outwards, up the metal blinds between the blinds and the antenna.
I can guarantee you that it is not the neoprene itself which does it.
It could be residual Zn
My TW4722 GNSS active antenna is on a 100 mm stainless ground-plane,
placed on 2" of wood on a window sill behind two panes of glass, between
metal blinds and the glass, almost touching the glass. Feeds a NEO-M8T.
Late yesterday I placed old neoprene rubber mouse pads, rubber side
outwards, up
Hi,
I know. In practice many of the operators in the US is working together
to get smarter, share experiences and learn from each other and others.
Good folks.
Cheers,
Magnus
On 02/11/2017 04:08 PM, Bob Camp wrote:
Hi
To be fair to these guys, they have a number of challenges that have noth
I don't have an M8T, only an M8.
Heather defaults to showing up to 14 satellites. You can specify more sats or
a dual column display using the SI or GCT commands or you can click the mouse
on the satellite info table.
You can also use the SG command to set the GNSS configuration, but version 5
In message <9fd9beca-832a-4c38-9799-4a31625f7...@n1k.org>, Bob Camp writes:
>Not an easy thing.
Not even close, which is precisely why the "50/60 Hz or bust" mindset
doesn't work any longer.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since
In message <2126b261-3e4e-46d4-9181-1fb368244...@n1k.org>, Bob Camp writes:
>One *could* make a WWVB “new modulation” receiver with some sort
>of MCU demo board and a handful of parts. It would be fine for a basement
>lab / learning sort of project.
With reasonable OCXO as timebase, it w
Hi
One *could* make a WWVB “new modulation” receiver with some sort
of MCU demo board and a handful of parts. It would be fine for a basement
lab / learning sort of project. Given the way the semiconductor world works,
the longer you wait to start that project, the better a board you will have
as
Hi
Backing up a bit here.
> On Feb 10, 2017, at 7:35 PM, gkk gb wrote:
>
> Hello experts, I need a Rubidium frequency reference for my company, and
> wonder if I also need to GPS discipline it.
>
>
> I characterize crystal-based OCXOs for ADEV, MTIE, and TDEV, and my longest
> measurement
Hi
To be fair to these guys, they have a number of challenges that have nothing to
do with technology. They cross link to other companies and have little control
over how each one operates. Here in the US, we have multiple regulatory
agencies (it happens at the state, federal, and international
Work is already underway to improve the relicense of power grid
operations. They is smarting up quickly. The PMU/synchrophasor
measurements depend on UTC and before it can be used full-blown for
operation the single point of failure needs to be handled.
Cheers,
Magnus
On 02/09/2017 11:19 PM,
Hi Jim,
On 02/09/2017 11:39 PM, jimlux wrote:
On 2/9/17 1:31 PM, Poul-Henning Kamp wrote:
In message
<4fbdd81ddf04fc46870db1b9a747269202916...@mbx032-e1-va-8.exch032.ser
verpod.net>, "Thomas D. Erb" writes:
I was wondering if anyone was familiar with this proposal, is this
a uncoupli
From: gkk gb
Hello experts, I need a Rubidium frequency reference for my company, and
wonder if I also need to GPS discipline it.
I characterize crystal-based OCXOs for ADEV, MTIE, and TDEV, and my longest
measurement time is 100,000 seconds (28 hours).
[]
===
On Thu, 9 Feb 2017 17:19:49 -0500, you wrote:
>Isn't this "hard" lock to UTC creating a single point of failure? A
>solar burst, an EMP, or
>a software error could leave us all in the dark. After all, smart
>inverters could be
>programmed to act like big lumps of rotating iron and be compatibl
On Thu, 9 Feb 2017 19:06:51 -0500, you wrote:
>One simplistic way to look at all this is that a switcher presents a negative
>resistance load. If you drop voltage, current goes up. OCXOs happen
>to share this issue. Negative resistances are *not* what most power source
>guys want in their cont
On Thu, 09 Feb 2017 23:39:24 +, you wrote:
>It is harder than it sounds.
>
>Small solar inverters are the best, they an regulate down at milliseconds
>notice, and many jurisdictions impose asymetric frequency bands on
>them to exploit this.
>
>Big inverters, no matter what you put behind them,
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