The S A D data display plots the raw signal level data... it is basically the
satellite position map with the trails showing the signal level.
The S A S signal display does an interpolation between the various satellite
signal level data trails to fill in the blank spaces in the signal
I checked my neutrino detector yesterday and detected some of those faster than
light neutrions tomorrow ;-)
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All this talk of old digital clock chips reminded me of my first digital
clock... built almost 40 (EGAD!) years ago with a Mostek MK50252 clock chip
from Radio Shack (when those words weren't a travesty). And it had utterly
unbobtainium GREEN LED displays. It stopped ticking in the last
I now have my house converted over completely to LED bulbs... over 300 of them
(mostly PAR16/PAR20/PAR30/PAR38 bulbs)! At retail the cost would have been
over $15,000 dollars!!! Totally insane... I have a large closet totally
dedicated to light bulbs.When incandecents/halogens are no
I have used a company in Wyoming called Bomarc Services to reverse engineer
boards. They work for dirt cheap and do an excellent job. If you let them put
the results in their resale library, they work for cheaper than dirt.
I seem to remember that their rate was around $20 and hour... half that if you
let them put the results in their for sale library.
They did a 6x8 four layer board with components on each side for less than
$250. It had a off-the-shelf DC-DC converter brick on it... the board came
back with
Using the cable delay message is probably not a good idea... it resets the
internal filters and state every time you change it.
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Yes, at one time there was some very precision surveying antennas that were
temperature controlled. I'm not sure if they were just controlling just the
preamp or the whole antenna, but I got the impression that they were
controlling the temperature everything inside the radome package.
At
I believe that the Thunderbolt firmware would catch such a thing.There is
quite a bit of error checking and TRAIM (time receiver autonomous integrity
monitoring) done.
If the osc was off in freq, the firmware would try to use the EFC voltage to
slew it back into agreement with the GPS
1 ppm at 10 MHz is 10 Hz. It's been quite a while since I tested it, but if
I remember correctly, if the Tbolt OCXO is off that far the GPS won't lock and
the failure will be rather obvious.
The typical Tbolt oscillator has a DAC gain of 3.5 Hz/V. 10 Hz would be 3V of
DAC offset. Lady
If you have a Thunderbolt, Lady Heather will sync your time for free... It
can sync the time via a keyboard command (TS) or via command line options on a
regular basis, or whenever the system clock and GPS clock differ by a given
amount. You can specify the inherent delay between the
The good Lady Heather can display temperature values in all sorts of archaic
measurement systems. And buried in there somewhere (I think its still there)
can display phase errors in femtofortnights.
I once worked for a company famous for its insistence on endless specs and
paperwork that
Lady Heather depends upon the ability of the Thunderbolt to broadcast the time
message automatically every second. Apparently the Palisade type units do not
support this mode of operation. It might be possible to set up the software
so that it requests the time message continuously and
How about using Hostess Twinkies? They look like they would have good
insulating properties and are well known to never, ever decompose ;-)
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Check out http://dorkbotpdx.org/wiki/pcb_order You get three boards for
$5.00 per square (or round, triangular, oval, etc) square inch ($1.67 sq/in).
No setup charge, no shipping charges in the USA. Top quality boards (gold
plated) made in the USA. You can send him Eagle or Gerber
Google water slide decals for everything you want to know and need... there
will also be links for rub-on decals.
And check out tagopappadecals.com for info and supplies for making water-slide
decals (like used on model cars and airplanes). They can also make decals for
you.
The Tbolt does not have any sawtooth error or corrections. Its' GPS receiver
LO is generated from the 10 MHz oscillator. That's what makes it the best
GPSDO out there.
--
I'm also thinking of porting over much of the Lady Heather t-bolt monitoring
stuff to the Arduino.
These are 4-BYTE single precision floating point numbers, not 4 bit integers.
They are the values plotted in the Lady Heather PPS and OSC graphs (and used
in the ADEV calculations and plots (not actually true ADEV values since they
are not refereneced to an external reference, but still
I have had several HP-5370's with the 10544 oscillator. They consistently
have much less long term frequency drift than the 10811's. If they have not
been powered on for a long time, they do take a couple of months of power-on
aging before they settle in.
Uhhh... last time I checked 3V/330 ohms is 9.1 milliamps, not 90 mA...
-
Just calculate: 5V supply, approx 2V LED voltage - 3V over the resistor.
3V/330R = 90mA
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It's slated for destruction around December 21 of this year...
We already have one of those that everybody can use. It's called the
earth.
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Lady Heather supports several versions of the Mayan and Aztec calendars (plus a
bunch of others). You can also specify a correlation constant offset to match
the date to whatever value your local high priest deems correct.
---
I thought the same thing but I think Mark
John,
Did you ever run any tests on those UCT double oven OCXOs? I've found them to
be freaky-stable long term. I have retrofitted a lot of Tek DC510/5010
counters with them and after over two years, the last digit is still right on.
They are capable of great
Lady Heather's osc drift rate calculation does assume that the temperature has
been stabilized. John DuBois and I did quite a bit of work to find a way to
unwind the osc parameters from the available unstabilized reported data using
SciLab on the log files, but nothing seemed to work
I make backup images of all my EPROMs and even bipolar devices. I even built a
device for reverse engineering secured PALs. I have a fully configured Data
I/O Unisite for programming. This machine with all the device adapters, etc
cost somebody well over $100,000
The Unisite is probably
The bad temperature sensors can have a rather dramatic effect on the tbolt
output, particularly if you are even remotely time-nutty. Their disciplining
algorithm seems to use it as a rather important number.
And the bad sensor is rather useless if you are trying to use Lady Heather to
HP had a program called NOMAS (Not Manufacturer Supported) where they did
release the source code to some of their calculator products (mainly the HP41
family) and possibly others. There are many great HP41 (and other calculators)
emulations out there because of it.
I really wish they'd do
All of those ADEV curves are awful... send me the oscillator, and I will
dispose of it properly ;-)
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On my 5065A, the 2nd harmonic reading jitters between 35 and 40. Not sure if
this is normal or not, but the output seems very stable. The std deviation of
the output time interval on a 5370A clocked by a tbolt is at the limit of the
counter when it is clocking itself.
Well, you could just toss a Thunderbolt into the box and use Lady Heather to
do the temp control. Using just a fan and cardboard box and maybe some thermal
mass, you can stabilize the temperature to within a few millidegrees
(microdegrees long term average) as long as the desired temp is
It's not exactly a USB dongle, but if you have a Thunderbolt, Lady Heather
has a time sync command that sets the system clock to Tbolt time. You can have
it set the clock periodically or whenever the system clock diverges from Tbolt
time by a specified amount (including 0 milliseconds).
One thing to be aware of with the LM35 type of sensors in the TO92 package is
that virtually all of the temperature input to the chip is via the leads (fine
print in the data sheet). I have seen several places with the device package
epoxied to some surface or embedded in some insulation with
Lady Heather has an oscillator autotune function (a from the keyboard) that
sets reasonable values for a lot of the oscillator and filter parameters. The
oscillator autotune function determines the oscillator EFC gain value, then
sets that, the damping factor, the time constant, and the
Switch back to degrees C. There is a bug... uhhh... undocumented feature that
affects the graph scaling in any of the alternate temperature systems. Should
be fixed shortly...
You can store the command line options (one per line, with the / in column
1) in the file HEATHER.CFG Type '?' and scroll down to the bottom of the help
window to find where to put the file. Heather will read the .CFG file on
startup.
You and also store keyboard commands in a .SCR file
And any similarity is purely coincidental ;-) Lady Heather was Lady Ada's
wicked stepsister, master of the tight bustier, cracker of the leather whip,
instiller of heavenly discipline. Oh! really? ;)
El 04/12/2010 23:47, Rix Seacord escribió:
Charles
I'm not sure it was the source but
A little off topic, but needed for a time-nutty application: 4 channel scope
with isolated inputs that is affordable. I have a 2 channel Tek THS730A. The
Tek TPS2014 is rather pricey. Does anybody know of something affordable?
A much simpler solution is to dedicate a $20 obsolete laptop to the Tbolt. I
use a 200 MHz Compaq Armada with 1024x768 screen. I have also run Heather on a
90 MHz Fujitsu Milan with a 640x480 passive matrix screen.
For bonus points, tap off the internal laptop CDROM power connections (and
All you 16500 logic analyzer users out there may or may not know that the
machine only works with Quantum Fireball disk drives with less than 2 gig
capacity. The analyzer firmware issues some undocumented IDE commands during
the boot sequence. You also may or may not know that those early
Lady Heather will display the date (but not fractional time) in MJD with /DM
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and
Heather now has an option to display MJD.fraction ... but, alas, release won't
be for a while...
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Carefully drill small hole in the switch housing. Use a hand pin vise, you
don't want the drill to damage the switch works. Orient the drill pointing up
so shavings don't fall into the switch. Then spray your favorite contact
clean/lube into the hole. Works well for most switch problems
Anybody got 'em? They are not in my copy of the service manual.
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and follow the
I bought some spare 5372A CPU boards. One of them failed the histogram
hardware test. Looking at the histogram/timing board schematic, the only
histogram specific chips on the CPU board seemed to be a decoder and a couple
of buffers. I replaced the decoder and the problem got worse with
From working on a few dozen 5370's with the oven oscillator option I can tell
you that an oscillator that had been powered off for a long time (months to
years) takes at least a couple of months to settle in. And 10544's behave
quite a bit better than 10811's when it comes to aging.
Using Lady Heather's temperature controller (fan+cardboard box+solid state
relay+baffling and thermal mass to taste) I get around +/- 3 millidegree
temperature control when the AC/furnace is not running and +/- 20 millidegrees
with them cycling. Long term temperature average is down in the
Baring any holdover events, the long term output of a properly configured
tbolt should exceed any single cesium source or maser. If you assume the 1 PPS
signal is always accurate to 5 ns that is an error of 1 part in 1.6E16 at
tau=1 year.
Also, there is code in Lady Heather that
If you've ever worked on more than a very few Tektronix TM-500 series modules,
you are well aware of the favorite epoxy dipped tantalum capacitor failure
mode... very low resistance dead short... usually ending up in a charred
stinky black blob. Whatever manufacturer they chose... was the
There is some info on implementing the temperature controller in the comments
at the start of the file heather.cpp
You can use something the simple single ended transistor driver that Warren
described or use a DC solid state relay. The program can manipulate two of the
RS-232 port control
You don't... that feature is in 3.0 under the S)urvey A)ntenna menu
---
How do I start the Signal strength vs az/al display?
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Yes, the signal/antenna plot data is always being collected and does not
interfere with the program operation. You can clear the data and start
collecting again from scratch. You get a pretty good picture of your antenna
after around 12 hours. There is very little info to be gained after
You can specify the com port number on the command line. COM2 would use the /2
parameter, etc
If you type in ? from the keyboard or /? on the command line you get a dialog
box that shows most of the command line options.
-
Is there a way to make Lady Heather 'wake up'
Generally you have to do some playing with the fan position and internal
baffling and thermal mass for best performance of the temperature controller.
You don't want direct airflow onto the tbolt. Also you probably don't want an
large/aggressive fan... a little airflow can go a long way.
Not mine, but somebody here is going to want this... doubt you will find
another one:
http://cgi.ebay.com/ORIGINAL-NATIONAL-RADIO-NC-2001-2011-CESIUM-BEAM-MANUAL-/150550832824?pt=LH_DefaultDomain_0hash=item230d8766b8#ht_1546wt_808
The KA4 fast autotune has a lot of limitations that make it unsuitable for
general purpose use. It bypasses a lot of the initialization and work of the
full (KA) autotune. It depends upon a stable temperature environment and the
proper initial state of the hardware. Most people should just
BTW, once you have the ability to control the Tbolt temperature you can get
the oscillator aging and temperature coefficients. You should first run (or
have already run) the 'a' oscillator autotune to get a good value for the
oscillator control voltage gain.
Once the unit temperature is
With the temperature stabilized, compared to just 1 degree swings in
temperature I see a 10 times improvement in the 1PPS standard deviation, and a
3 times improvement in the oscillator and dac control voltage.
-
Between that data and LH's EFC plot you should have
At one time I took some data on a 5370A with a FTS4060 cesium as the reference.
Those numbers tracked the self-reported numbers. I can't find the raw data
anymore.
Warren also pointed out that with the temperature stabilized you can increase
the filter time constant 2-3 times over what a
Heather started out as a AVR application on a MegaDonkey touch screen
controller (http://www.mega-donkey.com) but I quickly came to the conclusion
that it was much better suited to a dedicated $20 surplus laptop.
You can rather easily extract the temperature controller code from the source
The -12V supply on the tbolt is also used by the oscillator EFC dac (the EFC
voltage can go negative). Any noise on the -12V supply will be just as
effective as noise on the +12V supply at messing things up.
If anybody is looking for a spare 5372A CPU board... I have one.
Also, does anybody know of ROM images for the FFT option, or 5373A images?
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it doesn't have to be THAT complex. A 50 entry LUT is however expensive.
Yeah, might even cost as much as a whole US dollar (ragged as they are these
days). 512 kbyte EPROMs can be had for under $1... connect the outputs to a
resistor ladder (might need an output latch), filter, voila
Done it in the before - yes.
Done it in the kitchen / last 2 years - yes
Set up to do it in the kitchen - yes.
Would I buy one - probably not, given your constraints. Never build what you
can reasonably buy.
Would actually do it in a reasonable amount of time -yes
As far as the stencil is
Why Lady Heather, of course! Requires a Thunderbolt.
Use the S)urvey P)recision command. You can specify the number of hours to run
for (default is 48). During the survey all the fixes are written to the file
LLA.LLA and plotted on the screen (each hour in a different color). It does
The chip has 8 NC - No Connect pins... that must be connected to GND. What
will they think of next?
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To answer my own question... it's a ROHS lead-free device that contains lead!
--
What will they think of next?
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I downloaded the HP 5372A ROM images from Dieder's site, programmed them into
27C010's, installed them on a 5372A CPU board... no joy. System does not
boot. The status lights on the CPU board flash for a while, then stop with
the left three LEDs lit.
I tried the W9 ROM size jumper in
Remove the inverter circuit! It is not needed and might severely degrade the
performance due to temperature issues, etc.
You can specify the Tbolt DAC gain volts/Hz (both positive and negative values
can bee used) and save it into EEPROM. Lady Heather has an oscillator autotune
function
Yes, Lady Heather has some rather extensive calendar functions built in,
including a list of common (and not so common) holidays. If the file
heather.cal is found, it uses that file for the holidays... you can add your
own or delete some. Otherwise it uses the built in list. I don't
When you are viewing a time interval that is longer than one second per screen
pixel, the program must sub-sample the data. Every second the screen is
redrawn with a new set of samples. Also the plots are rescaled according to
the data being plotted (if auto-scaling is turned on). With
If your plot area is 1200 pixels wide and you are displaying 1 hour of data
(3600 seconds) then the data from every third second is shown on the screen.
The plot area is updated every second. If your spike event is one second wide
it would appear on the screen once every three seconds.
The
You can also stop a lot of the jumping around of plots by disabling the
auto-scaling of that plot (or all of them). You can also disable the
auto-centering. The default is to rescale and re-center the plots each time
the screen is updated. A short spike can cause the screen to rescale as
I have a sneaking suspicion that I know what is going on...
Ages ago I sent the code for my first TSIP parser to someone (can't remember
who... was it Dieder?) who was going to use it in a microcontroller based
tbolt monitor. Fluke's monitor is just a lift of that design. Well, my code
The spikes are due to an artifact in the way the Tbolt firmware reads the
temperature sensor chip. It reads two registers and combine the values to get
a high-res temp reading. But if the firmware accesses the registers in-between
the time that the temp sensor chip updates them it can
If you are going to use a laptop... might as well go with the ever handy Lady
Heather and a Thunderbolt. You can zoom either the digital clock or analog
clock to full screen. Plus it can do sidereal time, etc. You can even select
what brand of analog clock/watch that you prefer... even
The -12V is almost certainly used for deriving the tuning voltage. The unit
can generate a tuning voltage of -5V to +5V. To do this it needs a negative
supply... and there does not seem to be an on board bias generator for
generating the negative DAC supply. Becuase of this, for best
. The 16F84 EEPROM has a lifetime limit
of around 1 million write cycles. Also the writes to the AD9830A chip are not
synchronized to the output waveform. The output waveform glitches each time a
new divisor word is written.
Mark Sims
Dallas, TX
I will post a semi-schematic of the changes
I just posted my rather long dissertation on the FE-5650A and FE-5680A
synthesizer board. A critical observation is that the F=reference frequency
value returned by the S command is NOT the value that the unit is actually
operating at as shipped from the factory. It is the value that the
Attached is my program for calculating the frequency divisor words for the FEI
FE-5650A and FE-5680A rubidium oscillators with the AD9830A based DDS board.
It compensates for the difference between the R=reference freq that the 'S'
command returns (the minimum C-field value) and the frequency
Decent thermal management of the FE-5650A can be a problem. It is a small,
compact object dense with electronics and the rubidium physics package that
runs at over 100 degrees C. There are two metal plates in the unit. One is
the baseplate of the physics package. It is bolted edge on to
I recently measured the operating (baseplate) temperatures of several different
rubidium standards. These are all in free air without heatsinks. Results are
as follows (degrees C over ambient, warmest point found on device):
FRK-L:+21C
M100: +18C
LPRO: +24C
5650A: +35C
PTB100:
Also forget the complication of trying to trim the cable length... the effects
of temperature, humidity, pressure, moisture, etc in commercial TV cable
being used at microwave frequencies will rather quickly render your precise
adjustments moot.
A while back I did a project that used a 100 foot piece of (supposedly) fairly
good quality RG58. I checked it with my TDR and then installed it in an
outdoor application where it ran for a couple of weeks in good ole' Texas
weather. The outdoor connection was covered by a glass jar so water
Of course, any Time Nut worth the name would install a servo controlled
section of trombone line in his coax to maintain a constant electrical length
;-)
This demonstrates that achieving nanosecond propagation delay stability
is unlikely when using
Try SETUP, POSITION, (enter values from survey), SAVE SEGMENT... I think
that's what got mine to remember the results of its (3 days to complete) self
survey.
---
I am curious, however...how does one get TboltMon to SAVE the
surveyed position? It had the proper value
I suspect that there is an initial rapid aging process (break-in period) that
occurs followed by longer term aging effects (much like a crystal oscillator).
The particular cable that I used was not new, but had only been used indoors
before. I suspect that each temperature cycle a cable goes
I am thinking about writing a control program for the Thunderbolt that would
allow it to be controlled/monitored by a MegaDonkey LCD touchscreen based
microcontroller. The MegaDonkey is a Atmel ATMEGA2561 based controller with a
160x80 res touchscreen (see mega-donkey.com). It has two serial
According to the FRK manual it is a Winchester SRE-20SJ. I think they may have
a different part number now. The M100 manual references M28748-/8-D10L1A.
_
Now you can invite friends from
As part of my program that talks to the Thunderbolt, I have enabled and can
parse just about every message Thunderolts can produce. There appears to be a
problem in the 3F.11 and 5F.11 packets (EEPROM Segment Status). Sending a
3F.11 packet is supposed to return a 5F.11 packet that shows if
I am writing a program that talks to the Thunderbolt. The computer that I am
on is in a different room and they are connected by a 25 foot RS-232 cable. At
9600 baud I get occasional (mayby one in 1000 packets) glitches in the data
stream. The glitches do not show up with a 10 foot cable.
I recently bought a FTS-4060M/S24 cesium beam unit. It is a rather stripped
down model, with 1MHz on the front panel and only 1/5/10MHz/Fault BNC's on the
back (does not even have the monitor port on the back).
It looks like the tube is good. I can scan though the resonance peaks.
Turning
Hello Bjorn,
My OCXO is marked: Model 2000A Serial Number 311. No freq is given. It is
almost certainly 10 MHz.
The oscillator does have that weird D-SUB+coax on it. The PCB on the module
wires it to a DB9 connector with the Dataum 1000 OCXO. Measured voltages were
around 15V and 26V.
Here are the pinouts of the FTS 2000A OCXO jumper board in my 4060M/S24 cesium
beam unit.
This board makes the 2000A look like a Datum 1000 OCXO.
Datum 1000 pinouts and definitions are from Brooke Clark's PRC68.COM web site.
The FTS-2000A coax connects to an SMB connector.
FTS 2000A Datum
I am now fairly sure that the issues with my 4060 are due to a bad EPROM image
or some other problem with the CPU card. When I start an ALIGN sequence you
see the beam current jump up to the same point as when you turn MOD off. From
then on, nothing else happens. I would assume that the
Hello Magnus and Chuck,
The FTS-4060 is a steam driven machine from the last millenium. I don't think
it has a DDS chip.
Everything appears to be working and the physics package seem to be locked on
freq when I set it up manually. The problem is the auto-align function does
not work. The
I have written a little (2500 line) C program that parses all the Thunderbolt
and Thunderbolt-E massages. I'll post it after I scrub some code that can't
be shared. The program is actually written in Quick-C for DOS. Sholld be easy
to port to Linux by changing the serial I/O routines.
The Thunderbolt does not produce NMEA messages, so you would need to parse the
TSIP data stream. My C program to do that for all Thunderbolt messages is
around 2700 lines long.
LOCK on the Thunderbolt is not a simple question to answer with a single
blinkey light. There are many degrees of
One problem with the HP3325 is the max frequency of the triangle and ramp waves
is rather low (10 KHz). Ebay item 290241023737 is a 3325A with a rubidium
timebase.
If you can do with sine and square waves, the FEI-5650A and 5680A rubidium
oscillators can be made into nice stable sources
Try putting the output of a CD or FM radio signal into a FFT based waterfall
display. An amazing number of songs, etc have very prominent 15734KHz and/or
15.625KHz harmonics that are obviously from CRT monitors in the recording
booth. Recording engineers ain't what they used to be...
You
Bark effect? ;-)
Lightning hit a tree behind where I lived and three other trees near it also
exploded... you ain't gonna arrest a direct lightning strike.
---
Skin effect did not save the tree.
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