>From the description, it sounds like a HP 100D not a 10D.
John WA4WDL
Perry Sandeen via time-nuts wrote:
> List,
> Since I've been babysitting this unit for 20 years or so waiting for
> a-round-it to arrive its probably to to pass it on to someone who would
> revive it.
> It is a 100KH
Hi,
The GR 1101A thermometer thermostat is similar, but not the same dimensions.
The GR 1101A has one bent thermometer that is visible from the front panel but
does not have any contacts. The other thermometer/thermostat is deep within the
crystal oven, is also bent, and does have the contacts.
Yes, I have the 1190 crystal and the socket. That is one of the driving factors
for me to get the oscillator functional again. I am hoping someone has parts of
another 1101A that is missing the crystal bar.
John
Bob kb8tq wrote:
> Hi
>
> I have seen only one of them that still had the
I am trying to restore a clunker General Radio 1101A crystal oscillator. The
unit I have is missing several parts including the mercury thermostat switch
and parts of the oven box, and maybe more. I am looking to buying one or more
other clunkers to get at least one of these historic devices op
The voice announcement problem appeared to be fixed around 17:45 P.M.
John WA4WDL
jmfra...@cox.net wrote:
> I do not know if anyone else noticed, but since sometime before 17:00 UTC,
> the
> voice announcements on the 7.850 MHz signal have been messed up. Some times
> the announcements
I do not know if anyone else noticed, but since sometime before 17:00 UTC, the
voice announcements on the 7.850 MHz signal have been messed up. Some times
the announcements are missing, other times they are incorrect. I have not
checked the other
frequencies. I was working in my shop and switch
I meant to type 7.850 MHz, re-engaged brain.
John WA4WDL
jmfra...@cox.net wrote:
>
> I do not know if anyone has noticed, but since sometime before 17:00 UTC, the
> voice announcements on the 7.8350 kHz signal have been messed up. Some times
> they are missing, other times they are inco
Looks like I was able to reference your use of the three-oscillator technique
and highlight the history of the technique just minutes before your email to
the Time-Nuts Newsgroup. I originally referenced your successes in "Accurate
Zero Beating Using the Three-Oscillator Method," QST, Hints & Ki
A more accurate way to adjust for zero beat is to tone modulate one of the
signals. The waxing and waning of the tone is easier to discern than for the
background noise.
"Accurate Zero Beating, another perspective.
When trimming an oscillator so it or one of its harmonics zero beats with WWV
o
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Well done Tom! As always, you represented the Time-Nuts community in a most
professional manner.
John WA4WDL
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and follow the
A problem I had with TE heater coolers was condensation when the ambient
temperature was higher than the TE temperature. I was trying to operate the
crystals on the lower temperature inflection point. After a while, corrosion
became a major issue.
John WA4WDL
Bob Camp wrote:
> Hi
>
>
I noticed that NIST, at http://nist.time.gov/ , is still sending standard time.
When do they change?
John WA4WDL
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Actually, the bandwidth is 10 Hz not 100 Hz.
Joseph Gray wrote:
> Assuming I made the pictures small enough, attached are two images of
> an very old crystal filter that a friend found. The strange thing
> about it is the bandwidth - 100 Hz. What could this have been used
> for, with such a
1109, 1109A, or 1109B is correct. The military version is the OS-16/URM-18. The
1109B was set up for line, 100 Hz, 1 kHz, and 10 kHz. I have a few I enjoy. The
rear panel has 5 GR connectors. The CRT is a 3DP1, the same as used with the
I-152 indicator for the SCR-718 radio altimeter. The I-152
There are many options. Describe the connector(s). Some have more than one
connector. What have you applied to each pin? Do not say you applied +15v AND
+5V, etc. without saying which pins.
John WA4WDL
Bob Camp wrote:
> Hi
>
> There are far more unique pinouts for the 5680 than anybod
Go to http://novatech-instr.com/Fun/BlileyTCOSeries.pdf for a great chart for
Bliley crystal ovens, including the TC92.
John
WA4WDL
Mark Spencer wrote:
> Hi, I'm wondering if anyone has the pinouts or other info for a Bliley
> Crystal TC92 temperature stabilizer. This is a unit abou
I am looking for a General Radio Type 1101A crystal oscillator to rebuild or
use as a source of parts to rebuild an existing unit. I particularly need the
front panel thermometer and thermometer cover plus the main cover lid for the
crystal oven. Other parts would be a plus. A complete oscillat
The article says: "What time is it? The answer, no matter what your initial
reference may be — a wristwatch, a smartphone, or an alarm clock — will always
trace back to the atomic clock.
The international standard for time is set by atomic clocks — "
I always thought "atomic" clocks are maintain
I believe I would be interested in two.
John WA4WDL
Mark Sims wrote:
> I just finished laying out a small circuit board for building an extender
> cable for the Tek TM500 series mainfames / modules. Prototypes are off being
> fab'd at OSHPARK. Should be here in a couple of weeks. It u
http://www.ebay.com/itm/national-nc2001-atomic-clock-/181261183205?pt=LH_DefaultDomain_0&hash=item2a340228e5#ht_41wt_1071
John WA4WDL
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Yes, but put an isolation resistor between the output and the base of the
transistor, something between 3K and 5K should work. The LED will light upon
power on and extinguish when lock is achieved.
John WA4WDL
--
From: "Bob Stewart"
Sent: Saturd
Are you applying +5V to pin as well? See:
http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:fe5680a_faq
"Within 5 minutes after powering up (apply +15V on DB9 pin 1 and
+5V on pin 4) the unit should indicate lock (pin 3 voltage drops low)."
John WA4WDL
--
o slog through. I suspect there are other sat signals that
are better candidates.
Bob
On Jul 6, 2013, at 2:23 PM, jmfranke wrote:
A lot of the changes from "bent pipe" to the new system including C-band
uplink is explained here:
http://www.insidegnss.com/node/697
Sorry about the duplicates, email issue.
John WA4WDL
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A lot of the changes from "bent pipe" to the new system including C-band
uplink is explained here:
http://www.insidegnss.com/node/697
While there, downlink the extended PDF version.
John WA4WDL
--
From: "Magnus Danielson"
Sent: Saturday, July
--
From: "jmfranke"
Sent: Saturday, July 06, 2013 2:09 PM
To:
Subject: Re: [time-nuts] Speaking of Costas loops (WAAS)
A lot of the changes from "bent pipe" to the new system including C-band
uplink is ex
A lot of the changes from "bent pipe" to the new system including C-band
uplink is explained here:
http://www.insidegnss.com/node/697
While there, downlink the extended PDF version.
John WA4WDL
--
From: "Magnus Danielson"
Sent: Saturday, July
http://www.navipedia.net/index.php/WAAS_Signal_Structure
Doppler Shift: The Doppler shift, as perceived by a stationary user, on the
signal broadcast by WAAS GEOs is less than 40 meters per second (?210 Hz at
L1) in the worst case (at the end of life of the GEOs).
Carrier Frequency Stability: T
Exactly! It just seems like an interesting set of facts. I plan on doing
some more work on my WAAS dish antenna tomorrow.
John WA4WDL
--
From: "Dennis Ferguson"
Sent: Friday, July 05, 2013 7:55 PM
To: "Discussion of precise time and frequency me
http://www.navipedia.net/index.php/WAAS_Signal_Structure
Doppler Shift: The Doppler shift, as perceived by a stationary user, on the
signal broadcast by WAAS GEOs is less than 40 meters per second (≈210 Hz at L1)
in the worst case (at the end of life of the GEOs). The Doppler shift is due to
th
Valid concerns all. What I am building is a squaring circuit for recovering the
carrier from a WAAS GPS satellite. Granted there is still some Doppler and
other issues, but the accuracy would not be bad and it just looks like a fun
thing to do. Plus, I can use my four foot diameter dish antenna
For the VCO, how about a reactance modulator. They were very popular for the
sweeping local oscillator in many a panadapter. Or perhaps one of the voice
coil based wobbulators?
John WA4WDL
Bob Camp wrote:
> Hi
>
> I believe that if you dig into it, the correlator is either running qui
[time-nuts] Measuring speed of light or reproducing a metre
On 6/24/13 4:16 PM, jmfranke wrote:
The tuning fork was used with a clock. The clock was checked against
astronomical measurements.
http://www.schoolphysics.co.uk/age16-19/Wave%20properties/Wave%20properties/text/Speed_of%20light/index.h
The tuning fork was used with a clock. The clock was checked against
astronomical measurements.
http://www.schoolphysics.co.uk/age16-19/Wave%20properties/Wave%20properties/text/Speed_of%20light/index.html
http://www.nhn.ou.edu/~johnson/Education/Juniorlab/C_Speed/2007-PhysToday-RefFrame-Michels
I used UDT PIN10 photodiodes to observe the mode spacings in HeNe lasers.
The typical mode spacings were around 600 MHz.
John WA4WDL
--
From: "ed breya"
Sent: Friday, March 29, 2013 8:20 PM
To:
Subject: Re: [time-nuts] Photodiodes for high freq
$40
John WA4WDL
Mike Seguin N1JEZ wrote:
> I have a Shera control board that I haven't used in quite some time. I rely
> on my Z-3801A, Thunderbolts etc
>
> Time to sell it if there's any interest. I do not want to ship outside the
> US. It's currently still in the box where it was
How long do you let it run? Does the crystal oscillator oven get warm? If
you let it run more than 15 minutes, and the oven gets hot, the next thing
to check is the output frequency range as the tuning voltage sweeps. Not
having a frequency counter hurts but there are other methods. One is to us
I also have two of the crystals. The discs are used to adjust the phase of
the acoustic feedback to the resonator ends.
John WA4WDL
--
From: "Fabio Eboli"
Sent: Tuesday, January 22, 2013 7:14 PM
To: "Discussion of precise time and frequency measu
Would anyone happen to have a LHCP patch antenna, with or without preamp,
they would be willing to sell? I want to use it as the feed for a 4 foot
diameter F: 0.375 dish antenna for a dedicated WAAS receiving set up.
Thanks,
John Franke WA4WDL
4500 Ibis Ct.
Portsmouth, VA 23703
-
I do not have any data on temperature drift, but I can say that most YIG
oscillators I have used, with the exception of the Stellex-mini models, have
required a tuning current to oscillate. The Stellex-mini models have a
strong bias magnet which allows the tuning current to be zero at mid tuning
Take the "that" off the end of the address and it works.
John WA4WDL
--
From: "paul swed"
Sent: Saturday, December 01, 2012 10:10 AM
To: "Discussion of precise time and frequency measurement"
Subject: Re: [time-nuts] Loran
Not sure why the l
My main GPS receiver used to see four to six satellites at a time when I
used an antenna near a window in my workshop in a singe story house. I moved
the antenna up into the attic near the peak, added 25 feet of TV cable, did
not add any amplification, and now my system acquires and tracks eigh
Your 21 ns for 1PPS and T1 does not look too bad, but the satellite received
signal strengths are too low. You should have at least four or five SS
values above 60-80. I always have at least three SS readings above 100. My
Holdover runs between 03 and 4 microseconds.
John WA4WDL
See: http://en.wikipedia.org/wiki/Crystal_oscillator
BVA resonator (Boîtier à Vieillissement Amélioré, Enclosure with Improved
Aging), developed in 1976; the parts that influence the vibrations are
machined from a single crystal (which reduces the mounting stress), and the
electrodes are depos
If a civil servant was the inventor, the government is assigned the rights
and no one can use it for other than government applications without a
license. At one time I helped license government patents to companies.
John
--
From: "Jim Lux"
Sent
Now I need to find a 10 KW potentiometer!
John
--
From: "Jerry"
Sent: Monday, August 27, 2012 8:10 PM
To: "'Discussion of precise time and frequency measurement'"
Subject: Re: [time-nuts] Isotemp OCXO trimpot question...
I don't know if the l
There is no difference for a resistive load. For a reactive load, you have
to take in account the phase angle between the current and the voltage. If I
remember correctly, power = Volts X Amps X cosine of the phase angle. Some
refer to the phase angle as the power factor.
John WA4WDL
---
Have you tried commanding a survey to get the receive to ignore the old
location?
:PTIME:GPSYSTEM:POSITION:SURVEY ONCE
John WA4WDL
--
From: "Morris Odell"
Sent: Saturday, August 11, 2012 7:27 AM
To:
Subject: [time-nuts] Fun with the Z3815
HI a
Set the scope sweep speed to 10 milliseconds per division and then even a
dull scope is easy to see. You are looking for trigger events from the 1PPS,
not the 1PPS itself.
John WA4WDL
--
From: "C. Turner"
Sent: Monday, July 23, 2012 2:26 PM
To:
Do not be too quick to toss out the antennas. Some receivers need the
antenna power to be connected to a pin on the receiver connector that is
then internally routed to the antenna.
John WA4WDL
--
From: "Stephen Farthing"
Sent: Monday, July 23,
Was it GWEN (Ground Wave Emergency Network)? When it was shut down, many of
the transmitter sites were scheduled to be used as part of an inland LORAN
system run primarily for the railroads.
John WA4WDL
--
From: "Don Latham"
Sent: Sunday, July
Yes it can have a fall back second although the probability is small, the
Earth's rotation rate would have had to increase. But the deciding committee
allowed for both + and - leap seconds.
John WA4WDL
--
From: "Chuck Forsberg WA7KGX N2469R"
Se
My GPScon program connected to my Z3801A still shows leap second pending.
John WA4WDL
--
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When I was in college, I worked part time on the engineering staff of
several AM broadcast stations. The employment contract forbid me from
working at another station within 250 miles if I was dismissed or resigned.
The clause was not limited to just the on-air personnel.
John WA4WDL
---
Jim,
Look at:
http://www.venus2012.de/venusprojects/photography/basicideas/basicideas.php
http://www.didaktik.physik.uni-due.de/~backhaus/Venusproject/mercury2003.htm
http://www.exploratorium.edu/venus/question4b.html
John WA4WDL
--
From: "Jim
Of course the answer depends on what you mean by noticeable extent. I am
assuming the mast is less than 3' in diameter and the GPS antenna is at
least a foot away from the mast. I would say for position error larger than
three feet, no and for timing errors larger than 5 nanoseconds, no. This of
Yes, but the propagation times are the times from each satellite antenna
phase center to the phase center of the receiving antenna. From that point
forward, the relative time delays are unchanged. It is the same as if one
was to record the RF signals at the back of the receiving antenna and then
I meant to type GPS repeaters not GPS receivers
John WA4WDL
--
From: "jmfranke"
Sent: Thursday, April 12, 2012 12:28 PM
To:
Subject: Re: [time-nuts] Best location for a GPS antenna...?
You must read:
http://transition.fcc.gov/eb/O
You must read:
http://transition.fcc.gov/eb/Orders/2005/DA-05-2998A1.html
Which discusses a FCC complaint with Navtech for selling GPS repeaters.
An exert is presented below:
``Please note: re-radiation kits are currently only
available for purchase to International Customers and in
You must read:
http://transition.fcc.gov/eb/Orders/2005/DA-05-2998A1.html
Which discusses a FCC complaint with Navtech for selling GPS receivers.
An exert is presented below:
``Please note: re-radiation kits are currently only
available for purchase to International Customers and in
Delay of the complete ensemble of signals results in a time shift much like
the addition of cable between the antenna and receiver. The position
solution will be the location of the first receiving antenna.
John WA4WDL
--
From: "MailLists"
Sent
David's comment on the direct and retransmitted signals is right on point.
You are creating a multipath environment with increased signal strength and
matching polarization. Even with no amplification between the antennas, you
are generating multipath signals for you and your neighbors.
Advoca
Bias T yes, but also a light load on the receiver antenna jack to let the
receiver know there is an external antenna and thus switch from the internal
patch antenna to the external antenna jack. I determined the required load
resistance by using a resistance box coupled to the antenna and starti
Shame you do not have a Hall effect probe to drag down the trace.
John WA4WDL
--
From: "Magnus Danielson"
Sent: Friday, March 23, 2012 4:58 PM
To:
Subject: Re: [time-nuts] Anyone familiar with SR-620 repair?
On 03/23/2012 09:30 PM, J. Forster
First, try counting the Rd reference frequency output. If one reads right
you are halfway to solving the problem.
John WA4WDL
--
From: "Jerry Mulchin"
Sent: Wednesday, March 21, 2012 8:05 PM
To:
Subject: [time-nuts] Frequency Counter Errors
I
It would make an awesome display!
John WA4WDL
--
From: "Bill Hawkins"
Sent: Saturday, March 03, 2012 11:32 PM
To: "'Discussion of precise time and frequency measurement'"
Subject: Re: [time-nuts] Questions about Austron 5000 Loran C receiver
Make that -1.85 seconds per YEAR!
John WA4WDL
--
From: "jmfranke"
Sent: Friday, March 02, 2012 11:10 AM
To: "Neville Michie" ; "Discussion of precise time and
frequency measurement"
Subject: Re: [time-nuts] Sid
I used a PLL to convert 60Hz solar to 60Hz sidereal by multiplying by 1465
and then dividing by 1461. The error is -1.85 seconds per day (see: Reid,
Frank and Honeycutt, Kent;"A Digital Clock for Sidereal Time," Gleanings for
ATMs, Sky and Telescope, July, 1976, pp.59-63).
John WA4WDL
---
For a rough determination; you are facing due south, or due north when the
elevation of a celestial body stops increasing with time. The elevation is
highest when the body is on the observer's local meridian. There are
exceptions, for instance when observing a body below Polaris, then the body
ven the hour is very good
that puts you in the correct time zone
On Tue, Jan 24, 2012 at 9:54 AM, jmfranke wrote:
In addition to the moons of Jupiter, there was a method in direct
competition with Harrison. It was the Lunar distance method. The Lunar
distance method used the position of the Earth&
If it is the instrument I remember, the tuning fork was used to generate the
drive for a synchronous motor. The motor drove a disc with hole patterns at
different radial positions. The frequency control moved a photo cell
assembly to pick off the different frequencies from the disc.
John WA4W
In addition to the moons of Jupiter, there was a method in direct
competition with Harrison. It was the Lunar distance method. The Lunar
distance method used the position of the Earth's moon against the zodiac as
a clock. The term lunar distance was used because the navigator measured the
angul
Mine reads:
MAX3232EWE
0332
and has a 16 SOIC(W);16 pin package.
John WA4WDL
--
From:
Sent: Friday, January 13, 2012 2:17 PM
To:
Subject: [time-nuts] 5680 RS232
Can some one tell me which RS232 chip is used in the 5680.
Thank you.
__
John M. Franke WA4WDL
4500 Ibis Ct.
Portsmouth, VA 23703
--
From: "Jim Lux"
Sent: Sunday, January 08, 2012 1:33 PM
To: "Discussion of precise time and frequency measurement"
Subject: [time-nuts] Free bare board for Shera controller
The one fro
The satellites use helix antennas.
John WA4WDL
--
From: "Azelio Boriani"
Sent: Saturday, January 07, 2012 11:29 AM
To: "Discussion of precise time and frequency measurement"
Subject: Re: [time-nuts] Getting my Rockwell D200 GPS to work
Just
Congratulations on a job well done and a saved prize piece of technology.
John WA4WDL
--
From: "Frank Stellmach"
Sent: Saturday, January 07, 2012 9:17 AM
To:
Subject: [time-nuts] HP 10811-60111 - successful repair of NTC damage
Dear time-nuts,
Balsa wood is good and is readily available from Hobby Shops. Or Gator board
(paper laminated on foam) also called foam board from Art's and Craft
stores.
John WA4WDL
--
From: "John Ackermann N8UR"
Sent: Friday, January 06, 2012 2:39 PM
To: "Di
On start up from cold condition, 15V at 1.8Amps -2.1Amps (27W -31.5W)
Running after warm up, 15V at 800mA (12W)
Plus 5V at 85mA (0.425W)
John WA4WDL
--
From:
Sent: Thursday, January 05, 2012 9:11 PM
To: "Discussion of precise time and frequency m
There will be a leap second the end of June 2012.
John WA4WDL
--
From: "IERS EOP Product Center"
Sent: Thursday, January 05, 2012 9:16 AM
To:
Subject: Bulletin C number 43
INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS)
A startup current of 0.95A at 5v implies a power of almost 5W and that is
way above the spec value <3.3W. That is another vote for the oscillator
being 3.3V.
John WA4WDL
--
From: "Dan Rae"
Sent: Friday, December 23, 2011 10:27 AM
To: "Discussio
I tested a couple of the oscillators. The Reference Output Voltage does not
plateau as the input voltage is increased. It does hit 3.00V for an input of
3.3V. It is at 4.5V when the input is 5v and keeps climbing well past 5V as
the input voltage is raised. So, it appears to be a simple 0.9 time
I have a FE-5680A that goes through a normal start cycle and the PLL locks.
If I interrupt power after the temperature has stabilized, the PLL will not
relock. I assume the VCXO has drifted out of the PLL lock range but is still
within the PLL hold range. Does anyone know what is the correct sol
There are several problems. First energy from the offending signal leaking
into the protected GPS band and second the GPS receivers having a bandwidth
greater than the protected GPS band in order to reduce phase errors, acquire
GPS signal energy present outside the protected GPS band to have a h
Helium does.
John WA4WDL
--
From: "Dick Moore"
Sent: Tuesday, September 20, 2011 2:39 PM
To:
Subject: Re: [time-nuts] Making a 10811 better
Is there a relatively inert gas that has much higher thermal conductivity
than air? Then a flask makes
The position is solely defined by the location of the antenna. Once all of
the satellite signals enter the antenna, the time differences are fixed,
only the absolute time changes. The GPS receiver computes the position of
the antenna using time differences. The coax cable length can affect the
I believe that should read WGS 84 not WPS84.
John WA4WDL
--
From: "Chris Albertson"
Sent: Tuesday, September 13, 2011 5:03 PM
To: "Discussion of precise time and frequency measurement"
Subject: Re: [time-nuts] Averaging Location for Position H
What is your reference for UTC time. It appears Boulder is broadcasting the
correct values for UTC, so the next element to examine is the reference to
which you are comparing Boulder's broadcasts. Could it be GPS time?
John WA4WDL
--
From: "Mik
of the books.
-John
On 7/13/11 8:05 AM, jmfranke wrote:
The original series was copyrighted 1947 by McGraw-Hill Book Company.
The agreement with the government was the copyright would later be
lifted. I know in 1964 the grey colored small size book series were
printed by Boston Techn
The original series was copyrighted 1947 by McGraw-Hill Book Company. The
agreement with the government was the copyright would later be lifted. I
know in 1964 the grey colored small size book series were printed by Boston
Technical Publishers, Inc. with no copyright.
John WA4WDL
I prefer an inexpensive pocket watch, which I carry everyday, everywhere. As
with John Harrison, I use it to carry time from one good clock to another. I
depend on its short term stability rather than its long term accuracy.
John WA4WDL
--
From:
The former.
John WA4WDL
--
From: "J. L. Trantham"
Sent: Saturday, June 11, 2011 4:16 PM
To: "'Discussion of precise time and frequency measurement'"
Subject: Re: [time-nuts] HP Z3801A, GPS vs UTC?
I have been wondering about this.
Since lea
GPS time differs from UTC by the number of leap seconds accumulated since
the start of GPS time. Reseting the GPS clocks each time a leap second
occurs would upset the code generators. The satellites stay in GPS time but
do transmit the difference between UTC and GPS time to allow receivers to
Very nicely done!
John WA4WDL
--
From: "W2HX"
Sent: Wednesday, June 08, 2011 10:13 PM
To: "'Discussion of precise time and frequency measurement'"
Subject: Re: [time-nuts] locate 6 digit digital clock
I picked up this chip to create a nixie
A precision oscillator that far off usually indicates the oven is
malfunctioning.
John WA4WDL
--
From: "Chuck Forsberg WA7KGX N2469R"
Sent: Thursday, April 21, 2011 10:31 AM
To: "time-nuts"
Subject: [time-nuts] Fix Trimble Oscillator??
Is it
Do they detect the light flicker or the ambient ac field. Light flicker is
120 Hz.
Very interesting,
John WA4WDL
--
From: "tom jones"
Sent: Wednesday, April 20, 2011 9:43 AM
To:
Subject: [time-nuts] 60hz disciplined watch
Most if not all Citi
25 Ohms.
John WA4WDL
--
From: "Don Otknow"
Sent: Wednesday, April 06, 2011 2:00 PM
To:
Subject: [time-nuts] Transmission line question
Hello,
If I have a pin with two 50 ohm lines leading in opposite directions from
its land (let's say they ar
When I made a 1PPS GPS interface to a one pulse per minute impulse clock
movement, I used a 74LS90 divide by 10 followed by a 74LS92 in combination
with a 74LS20 as a divide by 6. I also used the circuit to drive two Nixie
tubes to provide a seconds display. More details if you are interested.
You can download the Interface Control Document ICD200 at:
http://www.navcen.uscg.gov/pubs/gps/icd200/default.htm
The document includes, among many other items, the code generation
methodology for the GPS system. It shows the shift registers and gate taps.
Sincerely,
John WA4WDL
I believe the klystrons came from the Varian brothers in California, but
England sent us their multi-cavity magnetrons via Tizzard. Both were
essential. We gave them the duplexer.
John WA4WDL
--
From: "Lee Reynolds"
Sent: Monday, December 20,
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