You don't need to tie up a PC.It could likely output the WWVB
signal while it was also surfing the web and reading emails. 60KHz
is NOTHING compared to displaying a you-tube video
In fact I bet your 48MHz uP could directly synthesize the signal.
Look at the ratio of 48 MHz / 60 KHz. The uP
Did the utility replace the damaged equipment?
On Tue, Jan 3, 2017 at 9:33 PM Van Horn, David <
david.vanh...@backcountryaccess.com> wrote:
> I once had some odd equipment failures which we found out were caused by
> the line voltage being at 142V.
>
> This was in the mid 80's in Costa Mesa CA.
I once had some odd equipment failures which we found out were caused by the
line voltage being at 142V.
This was in the mid 80's in Costa Mesa CA. The tech they sent out told me they
had us on the wrong transformer tap.
Lowest I've seen was 70V in Hawaii, with everyone coming home about 5PM an
Sure. I considered software. But I'm a hardware guy. I like designing boards.
The rig was designed to do amplitude and phase simply. The final design will
have a $5 48 MHz microprocessor included. I'm using that one because of speed
and memory. When that proves out I might redesign for a $2 24 M
Leap seconds only matter if you are counting seconds. The power
line isn't. As long as they keep the frequency near nominal, they
are fine.
-Chuck Harris
J wrote:
> Power utilities tweak the system frequency on a daily basis to keep MAINS
> powered clocks correct. I wonder what their correction
HI
> On Jan 3, 2017, at 6:59 PM, Hal Murray wrote:
>
>
> kb...@n1k.org said:
>> They sell a lot of 24 bit audio DAC’s into that sort of gear. Team them up
>> with some DSP and you get all sorts of interesting data. The “one number”
>> that counts is the fundamental ….
>
> DAC?
>
Typo … so
Recently, I was invited to an event to celebrate the addition of a leap
second.
I thought I would provide the entertainment by bringing a suitable GPS
receiver
plus a laptop running Lady Heather. I had done this before, so I thought it
would be easy, but a whole collection of things went wrong, an
kb...@n1k.org said:
> They sell a lot of 24 bit audio DACâs into that sort of gear. Team them up
> with some DSP and you get all sorts of interesting data. The âone numberâ
> that counts is the fundamental â¦.
DAC?
There is a big market for high resolution ADCs in that area - one in every
It seems France's TDF timesignal (phase modulation of a 162 kHz carrier,
which until the end of 2016 also carried France Inter radio sound as
amplitude modulation) inserted their leapsecond a minute early.
Like MSF and DCF77, TDF transmits one bit per second, together composing
the exact time at
Power utilities tweak the system frequency on a daily basis to keep MAINS
powered clocks correct. I wonder what their correction strategy was for the
leap second?
On Tue, Jan 3, 2017 at 11:05 AM, Vlad wrote:
>
>
> Speaking about MAIN... I was interesting to see if "leap second" event has
> corre
I like the Bosch BME280 conneced to a Raspberry PI.
https://learn.adafruit.com/adafruit-bme280-humidity-barometric-pressure-temperature-sensor-breakout/pinouts
https://github.com/adafruit/Adafruit_Python_BME280/blob/master/README.md
-- Björn
Sent from my smartphone.
Original message
I've used the Dallas (now Maxim) Thermochron iButtons in several applications.
Looks like a thick coin with battery, ram and RTC built in. Even used dozens of
them map temperature distribution in a aircraft fuel tank. Also available as a
1-wire device. For precision I've used Pico Technology PT1
On 2017-01-02 12:18, Attila Kinali wrote:
Attila!
Nice to see you around here ond au der es guez nois!
May I ask what you want to achieve? Resp. what you need a 10MHz
reference for?
I've always been wondering about those devices, I guess out of pure
curiosity. Once I learned that those were
Hi Tom:
I've used the Onset data loggers and they are very inexpensive and work well.
As a plus they are PIC based so hackable.
Don't know about accuracy, resolution &Etc.
http://www.onsetcomp.com/products/data-loggers
http://www.prc68.com/I/Hobo.html
http://www.prc68.com/I/GPend.shtml
The "Pen
Thanks, I will look on Tom's site for the manuals. The last time I looked
into this, I think all I saw were copper cavities.
But I think some sort of design that required very minimal machining, and
much more "plumbing", would be what I would need to do a homebrew maser :-).
Tim N3QE
On Tue, Jan
Hi
Measuring line voltage for “official” purposes straight up with a lab grade
device that may
have a bandwidth of many KHz (or even 100’s of KHz) is generally not a good way
to go.
The line voltage is the value of the fundamental (50 or 60 Hz) sine wave. All
the other nonsense
that accumulate
Yesterday hackaday had a link to a humidy sensor comparison:
http://www.kandrsmith.org/RJS/Misc/Hygrometers/calib_many.html
Em 03/01/2017 16:03, Mark Sims escreveu:
I did a LOT of testing environmental sensors when I built my ultrasonic
anemometer weather station that is part of a rocket lau
On 2 January 2017 at 05:15, Jeremy Nichols wrote:
> Thank you for the detailed analysis, Bill. The voltage measurements I made
> in my garage laboratory were duplicated by the utility with their meter,
> which was connected at the service entrance.
I have just been chatting to a friend who was
The sensor Jim linked :
Temp/humidity with I2C interface
https://www.adafruit.com/products/1293
looks good - packaged, high res temperature, etc. It's not 'complete' in
that it's only a sensor, but you only have to attach a USB-I2C adapter.
Probably less work than connecting up the sparkfun boar
Hi
There’s always the “cool factor” of higher resolution. Apparently it’s not
enough
of a issue to make it a worthwhile market to serve.
Based on what has been tossed around, it sounds like an Arduino with some
bits plugged in is the low cost leader. 3D print up and enclosure and you have
it
It's not there on my copy either. A7 CPU is assembly level repair. All others
are component level repair.
Page 6-9 of the 05272-90016 service manual says:
The A7 board has eight 1 Mbit RAM ICs having a total system memory of 256K long
words,
each 32-bits wide.
And,
The program is stored in 768
Tim,
The EFOS2 uses an Aluminum cavity! So machining would be easier than
Copper!
The complete manuals with schematics are on Tom's Leapsecond.com site.
Making a homebrew Maser was bandied about a few years ago on TimeNuts.
Cheers,
Corby
___
time-nu
The good news is if the dataloger you get has a mems pressure sensor, you
will have a high precision temperature sensor, whether or not the product
software provides that resolution to you is another matter. In addition to
the piezo-resistive bridge being mechanically sensitive to diaphragm
strain,
I put some raw data here:
http://www.patoka.ca/OCXO/60HZ.logs.tar.Z
Unfortunately its not continuous, because of for some period of times my
machine was offline (software upgrades or my radio made some mess with
RF which affects the MCU and recordings. And I was busy with something
else to
I did a LOT of testing environmental sensors when I built my ultrasonic
anemometer weather station that is part of a rocket launch control system. The
best humidity sensor I found was the DHT21/SHT11/AM2301/SHT15. They run around
$3 and can also provide temperature to 0.1C res / 0.5C accuracy.
On 1/3/17 9:15 AM, Bob Camp wrote:
Hi
There is an ever increasing pool of good sensors to put into something like
this.
(More so for temperature and pressure. Humidity still is a bit of an issue.)
There’s not a lot to interface between the sensor and a USB “chip”. It’s
surprising
that there ar
I noticed following information (source:
http://www.mainsfrequency.com/news.htm#2015_1):
Minimum and maximum mains frequency
To clarify the question "how stable is the mains frequency", data of the
last 13 months was analyzed (July 2011 to July 2012). The greatest
fluctuations occurred regul
Hi
There is an ever increasing pool of good sensors to put into something like
this.
(More so for temperature and pressure. Humidity still is a bit of an issue.)
There’s not a lot to interface between the sensor and a USB “chip”. It’s
surprising
that there aren’t more cheap / high accuracy cho
These
https://www.adafruit.com/products/381
are .0625C resolution, 1-wire interface (temp only)
This one
https://www.adafruit.com/products/642
has Teflon insulation, for use at higher temps
Or this one, Temp/humidity with I2C interface
https://www.adafruit.com/products/1293
On Tue, Jan 3, 2017
Vlad
do you have that data for a longer period of time...say 3 to 6 months?
Dave
On 1/3/2017 11:05 AM, Vlad wrote:
Speaking about MAIN... I was interesting to see if "leap second" event
has correlation with MAIN frequency fluctuation
Here is graphs for the MAIN periods recorded. Note: T
All these (including the one I linked) seem to be 0.5C only.
This one gets to 0.2C : http://www.ti.com/tool/hdc1010evm
On Tue, Jan 3, 2017 at 4:09 PM, Paul Alfille wrote:
> If you don't mind using 1-wire sensors, there are many nice choices, like:
>
> http://www.embeddeddatasystems.com/Environm
On 2 January 2017 at 18:14, Poul-Henning Kamp wrote:
>
> In message qnosgqvz...@mail.gmail.com>
> , Tim Shoppa writes:
>
> >What modern loads are actually sensitive to high (say, +10 to +20%) line
> >voltage?
>
> In EU you're supposed to have 230V +/- 6% in your outlet.
>
> The way this
If you don't mind using 1-wire sensors, there are many nice choices, like:
http://www.embeddeddatasystems.com/Environmental-Sensors_c_44.html for
temperature/humidity/barometric pressure...
On Tue, Jan 3, 2017 at 10:22 AM, jimlux wrote:
> On 1/3/17 7:08 AM, Tom Van Baak wrote:
>
>> I have som
Speaking about MAIN... I was interesting to see if "leap second" event
has correlation with MAIN frequency fluctuation
Here is graphs for the MAIN periods recorded. Note: The data on the
charts is "smoothed" by Bezier curves
I could see some "surge" which starts to climb in December 30 and
On 1/3/17 7:08 AM, Tom Van Baak wrote:
I have some high-end temperature and pressure instruments. But for casual use
in my home and mobile timing lab I use Sparkfun Weather Stations. The old URL
is:
https://www.sparkfun.com/products/retired/10586
Replaced by
https://www.sparkfun.com/pro
I haven't used this current generation of loggers (I do have a couple of
older RS232 units) but there's quite a range at
https://www.lascarelectronics.com/markets/environmental/
On Tue, Jan 3, 2017 at 3:08 PM, Tom Van Baak wrote:
> I have some high-end temperature and pressure instruments. But
I have some high-end temperature and pressure instruments. But for casual use
in my home and mobile timing lab I use Sparkfun Weather Stations. The old URL
is:
https://www.sparkfun.com/products/retired/10586
It's USB, talk-only, one reading a second, temperature, pressure, humidity --
abou
On 30 December 2016 at 23:58, Dr. David Kirkby - Kirkby Microwave Ltd <
drkir...@kirkbymicrowave.co.uk> wrote:
> I bought a 5370B TI counter which arrived today. It needs a bit of TLC,
> but nothing too bad. But one of the rotary knobs is incomplete. Does anyone
> have a spare knob? Contact me off
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