I collect clocks an have many clocks with 60Hz Synchronous Motors.
How would I go about Disciplining a 60Hz 120VAC source from an
Unintteruptable Power Supply (UPS)?
This would solve both my problem with power outages and the new problem
of possibly undisciplined power from the power companies
Don,
The easiest way would be to convert the line voltage to make a 12 Vdc
source, then use an inverter that you can add a xtal control to its
oscillator, or even add a GPS disciplined source to drive it. However, that
won't help with power outage, unless you would use a UPS, or maybe a
generator
I would suggest looking at double conversion UPSs. The plain UPSs put out
square waves (more or less). A double conversion UPS takes the mains, converts
to DC, filters it big time (easier to do with DC), the creates a true sine
wave.
These show up on craigslist often.
-Original
On Sat, Jun 25, 2011 at 9:50 AM, Don Mimlitch donm...@yahoo.com wrote:
I collect clocks an have many clocks with 60Hz Synchronous Motors.
How would I go about Disciplining a 60Hz 120VAC source from an
Unintteruptable Power Supply (UPS)?
Most comercial UPS are quite crude. Theu make square
There is a story about BF Skinner, the behavioral professor. His students
decided to change his behavior. They took the synchronous clock on the wall and
hooked it up to a variable frequency power source. Every class, they would
increase the frequency a bit. Skinner would teach faster and
Chris,
That's close to what I did, but I think the chips output to the switching
transistors was a modified squarewave, made to act like a sine wave, where
the waveform is stair-stepped. One could use a plain 60Hz crystal
controlled oscillator, and start out with push-pull amplifier stages to get
Depending on your skills and amount of time you want to spend on this:
1. As you said, find a commercial UPS and just tie it to a time-nuts
grade 10MHz. I assume most modern UPS will be based on a $1 ARM or PIC
processor - if they run on external oscillator you can use a DDS chip to
The cheapie inverters I've seen use a hgh frequency DC-DC cnverter to make
about 170 VDC, and then an H-bridge output stage, driven with a modified
square wave to make the AC.
Pretty crummy, IMO.
-John
==
Don,
The easiest way would be to convert the line voltage to make a 12
If I were tasked with this job, I'd buy an older UPS of adequate size for
your load, with the ability to use external batteries, that puts out
either sine or modified square waves. Older, because the controller will
be easier to modify.
BUT, before purchase, I'd make sure that, at least, a
All,
I thought I would share this, as it could save you some hard earned cash.
I just won a piece of equipment off ebay, and I knew what it weighed, and
it's size, when I bought it. It was to be shipped from Colorado to here in
Ohio. When the auction was over, I sent in the payment, but the next
I remember that on the NASA Manned Flight Tracking Stations during the
Apollo program, inside one of the racks of the timing subsystem was a
big Marantz HiFi amplifier. It was used to amplify a 60 Hz signal
derived from the Cesium reference to drive the common wall clocks that
were in many
The reason for using 12 Vdc, is that you can pick them up, and 24 Vac CT
transformer, on the cheap
That's a good point.So use two of them. One to power a high
current amp that produces a 12V AC signal from a high precision 60Hz
input. Then the other to convert the 12V to 120V. This
More clock memories...
I remember in school the wall clocks would synchronize. I assume their was a
company that made what we would call a networked clock today. This
synchronization would occasionally make the clock go backwards.
HP at one time had a Cesium reference/clock in the lobby of
Strongly suggest that you not only leave negative feedback but also send a
note to ebay, stating the circumstances. I had the same experience a year
or so ago, did both those things, and got an email back from ebay stating
that they would communicate with the seller. I anticipated he would give
I've got one of the cheap radio-controlled clocks? I was listing to radio 4 the
other day and herd the time signal. The radio controlled clock was about 3
seconds off. I was a bit surprised it was so far off. I'm just wondering how
accurate these things are.
--
A: Because it messes up the
Chris,
Yup, that's all I did. Use the line to keep the batteries charging, and
when the line goes down, the battery or batteries just keep on supplying
the system. Mine wasn't a sine wave though, but a modified square wave,
however it worked like a charm.
I got the idea from a website, and
I don't think Sellers can leave negative FB any more. They can give
non-payment strikes.
-John
===
Strongly suggest that you not only leave negative feedback but also send a
note to ebay, stating the circumstances. I had the same experience a year
or so ago, did both those
We are more a group of experimenters than lamenters, so
here's an open invitation to all of you in the US to join me
on a 60 Hz measurement party, starting as soon as you
can and lasting as many weeks or months that it takes to
get interesting plots.
There's no agenda; we measure because we can.
Hi David:
I've got a number of the WWVB clocks and can see a few of them at the
same time. It's common that they disagree by a few seconds.
Have Fun,
Brooke Clarke
http://www.PRC68.com
Dr. David Kirkby wrote:
I've got one of the cheap radio-controlled clocks? I was listing to
radio 4 the
Chris,
No I didn't say the output was 1000 Hz. No way.
What I said (a bit amplified) was that the cheapie inverters use a high
frequency, think 50 KHzish, DC-DC converter to make about 170 VDC, then
use that to feed an H bridge, driven with either a square wave or a
modified square wave, to
WWVB clocks look at the Time Code treansmitted by WWVB, not at the carrier
which is used for precision timing.
-John
==
Hi David:
I've got a number of the WWVB clocks and can see a few of them at the
same time. It's common that they disagree by a few seconds.
Have Fun,
John,
You're correct, they can't leave a negative now. eBay finally wisened up,
and saw that a lot of the feedback was retaliatory towards the buyers, and
took away this option. The only two negatives I ever received was over this
very same thing. One guy wouldn't abide by the auction, or what
I have two r-c clocks in the house and they both keep accurate time. One
clock is made by KLIK, the other by STAIGER - both from ARGOS.
The second-hand moves at the very moment I hear the pip, or as exactly as
the eye can tell. But I do not use Radio 4. Instead I check my times using
the pip
On 25/06/11 20:19, Dr. David Kirkby wrote:
I've got one of the cheap radio-controlled clocks? I was listing to
radio 4 the other day and herd the time signal. The radio controlled
clock was about 3 seconds off. I was a bit surprised it was so far off.
I'm just wondering how accurate these things
John,
I didn't mean to say you said all that, just that the new inverters are
cheap. I wrote that I thought some ran at around 1 kHZ, as I had an old one
that did, and used a toroidal transformer in it. The new ones, as far as I
am aware, are similar to the new-style switching power supplies,
Certainly, the inverters can run that low, but if so they sing a lot.
Best,
-John
=
John,
I didn't mean to say you said all that, just that the new inverters are
cheap. I wrote that I thought some ran at around 1 kHZ, as I had an old
one
that did, and used a toroidal
John,
Yes, this one whined when it ran. It was under the seat in a pop-up camper
I owned. It had a battery hold down in the floor, and the inverter was
bolted to the wall behind it. The only way to muffle the whine was to have
the seat cushion in place.
Best,
Will
*** REPLY SEPARATOR
On Sat, Jun 25, 2011 at 12:19 PM, Dr. David Kirkby
david.kir...@onetel.net wrote:
I've got one of the cheap radio-controlled clocks? I was listing to radio 4
the other day and herd the time signal. The radio controlled clock was about
3 seconds off. I was a bit surprised it was so far off. I'm
John,
I forgot to add, that an H bridge could work for a clock motor, since those
are used to drive ac motors in industry every day. You would have a sqauare
wave though, unless it was modified. If I recall, that's the way a lot of
the AC drives work today, using four sets of switching
Sorry, that should have said DC drive, as I was writing while brain
storming. However, a variable AC drive, which does control the frequency,
may be able to be used. I would have to look at this more, but it might be
possible, and these can be bought on the cheap at surplus sellers.
Best,
Will
On 06/25/2011 09:34 PM, Tom Van Baak wrote:
We are more a group of experimenters than lamenters, so
here's an open invitation to all of you in the US to join me
on a 60 Hz measurement party, starting as soon as you
can and lasting as many weeks or months that it takes to
get interesting plots.
John,
I forgot to add, that an H bridge could work for a clock motor, since
those are used to drive ac motors in industry every day.
Yes, of course.
You would have a sqauare
wave though, unless it was modified. If I recall, that's the way a lot of
the AC drives work today, using four sets
John wrote:
WWVB clocks look at the Time Code treansmitted by WWVB, not at the carrier
which is used for precision timing.
The ones I have do not monitor WWVB constantly -- they do it once a
day in the middle of the night (signal permitting), at which time
they synch up and update an
Hey Ed,
How are things in the land of mold, mildew and Jamesions?
Best 73,
Had
K7MLR
Typically better than 1s. If there is interference or the radio is disabled,
it won't be able to receive the time signal. Switch mode PSUs and CRT TVs
or computer monitors can interfere with the 60kHz
On 06/25/11 08:45 PM, Eamon Skelton wrote:
On 25/06/11 20:19, Dr. David Kirkby wrote:
I've got one of the cheap radio-controlled clocks? I was listing to
radio 4 the other day and herd the time signal. The radio controlled
clock was about 3 seconds off. I was a bit surprised it was so far off.
I took a look around at a few semiconductor manufacturers, and found an app
note from Freescale (Motorola), on their MC3PHAC AC motor drive chip. It
does use an external timebase of 4 MHz, but they only used a resonator, and
this could be made way more precise. Though this is a 3 phase controller
Ideally they are supposed to have less then 1/2 second of drift per
day and this get corrected to the nearest second every night when they
can connect to WWVB. But some might have more than 1 sec per day
drift and they might not be able to receice the WWV signal. Try
placing the clock some place
I have a RCA 4572 round scope CRT for sale, including the socket, mounting
hardware (face clamp, and neck tube), HV multiplier assembly, and the
transformer. I also have a 5 diagonal bezel, with the graticule insert,
and the mounting hardware to go with it (threaded studs). The CRT is a
round,
To see the effect of a WWVB watch self-correct each night:
http://www.leapsecond.com/pages/Junghans/
The raw data came from an inductive sensor and was compared
aginst a stable 1PPS.
/tvb
___
time-nuts mailing list -- time-nuts@febo.com
To
Great idea Tom!
I'm safely on my 50 Hz grid over here, so I let you guys play around in
your end.
Maybe we should do something on our grid, we are a few time-nuts on the
nordic grid.
Cheers,
Magnus
Magnus,
Yes, after the current 60 Hz excitement here in the US winds down
my longer-term
Hi Tom,
On 06/26/2011 01:07 AM, Tom Van Baak wrote:
Magnus,
Yes, after the current 60 Hz excitement here in the US winds down
my longer-term idea is for many of us to continuously monitor our
local power frequency with some sort of web-uploading TAPR kit
and then have an informal international
Extrapolating further, I wonder if anyone has done common view
time transfer based on synchronized power grids? Although not
as precise as LF or TV or GPS methods it would make a nice
demo of the concept.
/tvb
Interesting idea.. but here's a potential wrench in the works.. the
phase in the
On 06/26/2011 01:07 AM, Tom Van Baak wrote:
Extrapolating further, I wonder if anyone has done common view
time transfer based on synchronized power grids? Although not
as precise as LF or TV or GPS methods it would make a nice
demo of the concept.
/tvb
http://n1.taur.dk/plcv/
(with
An interesting question about making a 50/60 hertz source,
Does a 120 to 12 volt transformer have enough inductance to use as a
12 to 120 volt transformer?
Remember, the inductance is proportional to the square of the no of
turns, where as voltage is proportional.
cheers,
Neville Michie
RDS is a frequency standard?
-Original Message-
From: Kasper Pedersen time-n...@kasperkp.dk
Sender: time-nuts-boun...@febo.com
Date: Sun, 26 Jun 2011 01:53:02
To: time-nuts@febo.com
Reply-To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Subject: Re:
Neville,
Yes, it works just as well. I have seen companies use this to make tube
bias supplies, when all the windings wouldn't fit on one transformer. They
would use the filament supply, and tie the 6 or 12 volt coil of a smaller
transformer to it, then use the 120 vac side as the bias supply.
Yes.
-John
===
An interesting question about making a 50/60 hertz source,
Does a 120 to 12 volt transformer have enough inductance to use as a
12 to 120 volt transformer?
Remember, the inductance is proportional to the square of the no of
turns, where as voltage is proportional.
The C. S. Stong 'Amateur Scientist' anthology included a 110V 60 Hz
telescope-tracking drive generator project that used a reversed filament
transformer. It was a bleeding-edge design for the time, using a CK722 Wien
bridge oscillator (complete with HP-style pilot lamp AGC) and a couple of
early
On 06/26/2011 02:18 AM, li...@lazygranch.com wrote:
RDS is a frequency standard?
RDS can give time of day, notice how it says FM radio RDS+pilot CV so
the 19 kHz pilot tone is used in conjunction with RDS.
The danger in that is that RDS time of day setting may be bogus, since
some
Filament transformers do not saturate at normal input voltages. They only
saturate if the peak flux, integral of VdT, exceeds the acceptable value
for the core.
What does limit the current is the voltage sag due to the properly scaled
sum of primary and secondary leakage inductance plus
John,
A lot of it depends on the design of the transformer, or how close to
saturation its core is ran, and the way the laminations are stacked. The
inverters that were self-oscillating, and used tickler bias windings,
depended on saturation to work correctly, and the transformer determined
the
All,
The parts are sold, and thanks again!
Best,
Will
*** REPLY SEPARATOR ***
On 6/25/2011 at 6:09 PM Will Matney wrote:
I have a RCA 4572 round scope CRT for sale, including the socket, mounting
hardware (face clamp, and neck tube), HV multiplier assembly, and the
mag...@rubidium.dyndns.org said:
It could be interesting just to monitor the phase of the L1, L2 and L3
phases of the house. :)
Is 3 phase standard in (some/most/?) European homes?
In the US, houses and small businesses get 120/240. That's 3 wires, 240
single phase, center tap, with the
I wish we had three phase everywhere, including our homes. If one wants to
run anything like a lathe or mill of any size, we have to use converters,
or starters (static converters). When I had my shop, I contacted AEP about
installing three phase, and the cost of the transformer bank alone was
For any nixie tube fans, I ran across this HP 5245L Frequency Counter on
ebay earlier, starting off at $9.99.
http://cgi.ebay.com/T272-Agilent-5245L-HP-5245L-Frequency-Counter-/120742367
542?pt=LH_DefaultDomain_0hash=item1c1cce5136
Best,
Will
___
Now you can get true three phase delta, with speed control, from single
phase 220, non rotary. With wise buying, I got one to run a 1 hp mill
motor for around $100 inflated rasbuckniks.
Don
Will Matney
I wish we had three phase everywhere, including our homes. If one wants
to
run anything like
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