.
From: John Ackermann N8UR j...@febo.com
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Wednesday, 29 August 2012, 17:28
Subject: [time-nuts] Looking for HP 10638A
I'd like to find an HP 10638A degausser unit -- I'm lucky enough
Hi Eduardo --
For longer term measurements (e.g., tau of an hour or more) a very nice
and inexpensive counter is the HP 5334A/B. I haven't looked recently,
but in the past I bought several off eBay for $150 or less. They are
fairly modern, compact (2U high), and don't have a noisy fan.
Hi Bill --
Your lucky day may be at hand -- I've been struggling to get my herd of
Soekris 4501s running again and thought the process of updating from BSD
4 to 9 would be simple. Well, several months later I have a working
CF image and am just getting the four 4501s Soekris's (Soekri?)
This is probably something that very, very few other people are going to
encounter, but thought I would note it here for posterity.
I'm using the Soekris 4501 with high-resolution Elan CPU for nanosecond
timestamps as documented at http://www.febo.com/pages/soekris. When
using a PPS-only
Hi Grant --
Welcome!
I'd say you're doing OK; most frequency standards don't put a lot of emphasis
on harmonic purity in the specs. Better than 45dB down is pretty good, and not
much TF gear is highly sensitive to harmonics.
I would *not* add a bandpass filter unless you really need to.
I think there are now a couple of threads going on about this topic,
which I started by a clumsy attempt to use the WIDTH and HEIGHT
attributes in HTML. :-)
For what it's worth, I usually scale web graphics to no larger than 750
pixels horizontal or 550 pixels vertical. That goes back to the
Yup... I'm still playing with the screenshots from TimeLab; on my machine by
default they come out at 13xx pixels wide, and I usually size to about 700 wide
for web display. As an experiment, I tried using the WIDTH and HEIGHT
options in the IMG SRC tag, setting to a percentage rather than
Magnus inspired me to try my own cross-correlation experiment with the
TimePod today. I used two fairly normal OCXO frequency standards as the
reference, and a Wenzel 5 MHz ULN as the device under test.
By doing single-reference measurements of each OCXO versus the ULN, I
was able to plot
the data for the ULN
specifications?
On Sat, Aug 4, 2012 at 11:02 PM, Bruce Griffiths bruce.griffi...@xtra.co.nz
wrote:
John Ackermann N8UR wrote:
Magnus inspired me to try my own cross-correlation experiment with the
TimePod today. I used two fairly normal OCXO frequency standards
Magnus, this is very cool. Can you describe your cross-correlation
setup with the Time-Pod? I'd like to play with it here and compare notes.
John
On 8/2/2012 12:36 PM, Magnus Danielson wrote:
Fellow time-nuts,
I have borrowed Björn's FTS1200 and OSA8600 and that complements my own
Unfortunately, the TAPR T2-Mini divider
(http://www.tapr.org/kits_t2-mini.html) can't quite get to 1 MHz from 10
MHz with the PIC divider chip due to limitations in the chip architecture.
However, nothing says you couldn't dead bug in a decade divider chip
in place of the PIC, and let the
kHz output.
John
---
On 7/24/2012 1:05 PM, Chris Hoffman, KG6O wrote:
John,
That's interesting to me. What exactly are the actual structural limitations of
[that] pic?
-CH
On Jul 24, 2012, at 7:55, John Ackermann N8UR j...@febo.com wrote:
Unfortunately, the TAPR T2-Mini divider (http
TAPR has obtained a small number of used but tested Motorola GT+ and UT+
receiver boards. The gang here is probably most interested in the UT+,
which is an 8 channel receiver with 1PPS nominal accuracy of 50 nanoseconds.
TAPR is selling the UT+ receivers for $25 plus shipping, and the GT+ for
Hi Don --
The problem with the Clock-Block is that it can't generate exactly the
correct frequency in this case -- the closest it can get is several PPM
off. And, I'm not sure the phase noise/jitter from the Clock-Block is
good enough.
I don't know whether you could program a PIC to
I think a number of higher-end sound cards accept a word clock or
world clock (I've seen it both ways) that's intended to allow syncing
to an external source. The challenge I've seen is that the frequency
(either in the 12 or 24 MHz range) is one that's not simple to
synthesize precisely
I don't know if they've been discontinued, but a number of the M-Audio
cards had word clock inputs as well. They are/were pretty widely
available on eBay.
John
On 7/6/2012 11:24 AM, Azelio Boriani wrote:
OK, found it: the RME HDSPe RayDAT PCIe audio card has this reference but
with the
John Miles said the following on 07/01/2012 05:18 PM:
The real problem with the 5065A is that it represents the end of the line
for most noncommercial users. There are no further upgrade possibilities
for taus out to several hours -- not even the best commercial cesium
standards -- until you
I'll either be at the TAPR booth inside (booths 455-458, in the same vicinity
as the ARRL and AMSAT booths), wandering the flea market searching for The
Great Bargain, or hanging out at the flea spaces Bob mentioned.
We'll have a T2-Mini demo running at the TAPR booth (and product available for
Very cool, Magnus. Congratulations on your new-found fame!
John
On 4/25/2012 3:06 PM, Magnus Danielson wrote:
Fellow time-nuts,
Oh, ok. So now it is public, so I better tell you about it...
Jörgen Städje is a tech-writer which enjoys writing articles where he
dips into some system and
From the Sysadmin:
The server that febo.com runs on is getting a little long in the tooth,
and the amount of mail it processes never gets smaller -- remember that
time-nuts now has nearly 1200 members, and then think of the amount of
traffic the list sees every day. And, the machine does
The certificate error is because it's self-signed and not commercial,
which costs a chunk of change every year. We use SSL to avoid sending
passwords in the clear and not for ecommerce purposes, so (apart from
browsers complaining) there isn't any need for a trusted certificate.
The
On 4/16/2012 1:47 PM, Marvin Gozum wrote:
At eevblog.com forum Chinese scopes are a daily discussion for over 3 years.
In summary, in the= 100 MHz level they are very cost effective but there are
better and worse. Rigol, Owon and Hantek are on par while Atten and Uni-T are
consistently rated
I can put a wiki on febo.com if someone volunteers to manage it.
John
On Apr 8, 2012, at 3:09 AM, Poul-Henning Kamp p...@phk.freebsd.dk wrote:
In message 4228A5D7373F4DE7BD482AFEACF85458@narvik, David J Taylor writes:
This is the kind of important and detailed information I really
wish we
I haven't measured the video amps, but here are plots of an HP 5087A,
TADD-1, and Spectracom 8140 tap unit for a baseline:
http://febo.com/pages/amplifier_phase_noise/
John
Tom Knox said the following on 03/25/2012 03:48 PM:
Has anyone measured Phase Noise on any of these distribution
My SRS SR-620 counter died last weekend. After superficial
troubleshooting, it looks like there's probably a short on one of the
power supply rails. Symptom is that nothing lights up when power is
turned on, but one or more of the three terminal regulators gets very,
very hot (can't tell
Great advice. I have the manual, but it doesn't include schematics. I
think someone on the list has a PDF of the schematics, so I'll be
digging around for that before I start digging into the box.
John
On 3/23/2012 2:36 PM, J. Forster wrote:
Not w/ that instrument, but try the following. I
On 3/14/2012 6:22 AM, Attila Kinali wrote:
Hi,
I'm currently writing a short article on crystal oscillators and am
looking for plots of typical phase noise and ADEV of an OCXO.
But unfortunately, i couldnt find any, so far. Only discrete numbers
from the data sheets, or phase noise plots only
On 3/14/2012 1:35 PM, Chris Howard wrote:
These pretty ADEV/Tau plots, do people have an automated
system to produce these things? How much work is involved?
How many samples are taken? Sample for a month, omputer crunching
for weeks?
I have no feel for what the process is like.
I have two
Last evening I looked at my raw (but sawtooth corrected) GPS vs. Rb and
didn't see anything noteworthy.
John
On 3/8/2012 10:20 PM, Mark Spencer wrote:
Over last day and a half I've been comparing the 10Mhz output of my Jupiter
based GPSDO (actually a G3RUH GPSDO) to a BVA OCXO. So
On 3/8/2012 10:08 AM, J. Forster wrote:
The media is reporting a large solar storm and saying it will upset GPS
among other things.
Has anybody see any effects?
I won't be able to look at the data until I get home from work tonight,
but last evening I started measuring the sawtooth-corrected
An interesting complexity of any new Loran system is that it won't be
able to rely on GPS for time synchronization!
John
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On 3/5/2012 10:13 AM, Poul-Henning Kamp wrote:
In message4f54d075.6070...@febo.com, John Ackermann N8UR writes:
An interesting complexity of any new Loran system is that it won't be
able to rely on GPS for time synchronization!
Well, define rely. If they're using a Cs and GPS-steer
On Mar 1, 2012, at 11:41 AM, Brooke Clarke bro...@pacific.net wrote:
Are there any WWVB disciplined oscillators (WWVBDO)?
I have a couple of Spectracom 8164 WWVB DOs running. They bounce around by a
part or three in 10e10.
The 8164 uses an FLL that does 1000 second counts of the internal
There are a bunch of choices, some free and some limited to working with
a certain PCB shop, but I like Eagle (http://www.cadsoftusa.com)
because, among other things, it's cross-platform running on Windows,
Mac, and Linux (I use the Linux version). There's a free version and a
couple of steps
The 8170 isn't smart enough to calculate the leapsecond immediately.
Instead, it uses its error correction routine which takes about 4
minutes after the event to realize that it is one second off, then
updates the time to match. Details quite far down the page at
FWIW, I'm running an Atom D510 motherboard with an 8 port serial card.
I'm using Windows 7 and VNC for remote access (the machine runs
headless). I am regularly running LH v3 beta, TimeLab (reading PPS data
from a TIC), TAC32, and GPSCon each on its own serial port
simultaneously without any
give, a lot of uncetaiy to even prdict what the one day drift
will ber.if the Noise is not noise but due to Using a 10 day
ws
John Ackermann N8UR jra at febo.com
This isn't the real long-term stability test I'm planning to do, but I
did let the measurement continue
One thing to keep in mind is that FEI is very largely a defense
contractor, so their customers, marketing, and motivation are a bit
different than the typical business-to-business model.
John
On 2/17/2012 10:02 AM, Bill Riches wrote:
Good points made - no income for the company, However
When manually entering coordinates to the Tbolt, using either Tboltmon
or Lady Heather, is the altitude value to be entered as MSL or as GPS?
The Trimble docs don't seem to indicate which value is used.
Based on the surveys I've done with the Motorola receivers, at my
location there appears
That's an experiment I should run, but the current experiment requires setting
the Tbolt to the same coordinates as the other units, so I'm just looking to do
that. :-)
On Feb 12, 2012, at 12:42 PM, David C. Partridge
david.partri...@perdrix.co.uk wrote:
Or even better get Lady Heather to do
*
[time-nuts] Entering Altitude for Thunderbolt
John Ackermann N8UR jra at febo.com
That's an experiment I should run, but the current experiment requires
setting the Tbolt to the same coordinates as the other units, so I'm just
looking to do that. :-)
On Feb 12, 2012, at 12:42 PM, David C
Is there a recommended way to remove the residue of what I presume was thermal
tape on the heatsinks of my various telco Rb units? It's a slightly tacky
light greenish layer. I'm guessing that for a permanent installation one would
want to remove that residue, smooth the surface, and replace
I wasn't clear below -- the residue is on the Rb exterior surface that attached
to the heatsink.
On Feb 11, 2012, at 11:52 AM, John Ackermann N8UR j...@febo.com wrote:
Is there a recommended way to remove the residue of what I presume was
thermal tape on the heatsinks of my various telco Rb
work then try iso-propyl alcohol, acetone, tri-chlor, etc.
Those are more toxic, will attack plastic and paint, etc.
--- Graham / KE9H
==
On 2/11/2012 10:56 AM, John Ackermann N8UR wrote:
I wasn't clear below -- the residue is on the Rb exterior surface that
attached to the heatsink.
On Feb 11
Nothing new or exciting here, but I did some measurements of three GPS
sources -- M12+/TAC2, M12+/CNS Clock II with sawtooth correction, and
Z3801A -- to see what their short-term noise looked like, and got some
pretty pictures:
http://www.febo.com/pages/gps_pps/index.html
Thanks to John
On 2/9/2012 4:56 AM, Alberto di Bene wrote:
On 2/9/2012 3:36 AM, John Ackermann N8UR wrote:
As threatened, I've measured stability (out to a trustworthy 10K
seconds) and phase noise of the three popular telecom surplus Rb
standards. I looked at two units of the FE-5680, two units
On 2/9/2012 7:51 AM, WarrenS wrote:
Indeed,
ADEV is for random freq variation not easily measured by other means.
Temperature fluctuations do not cause random freq changes and the
temperature's effect should be removed if one wants accurate long term
ADEV numbers.
Even daily diurnal cycles due
Jim Lux said the following on 02/08/2012 07:17 PM:
On 2/8/12 3:23 PM, EB4APL wrote:
I want to take advantage of the topic just to ask if anybody has any
manual or schematics of the PTS 040. I realize that the PTS 160 is close
enough, taking in account the different frequency range, and they use
As threatened, I've measured stability (out to a trustworthy 10K
seconds) and phase noise of the three popular telecom surplus Rb
standards. I looked at two units of the FE-5680, two units of the
Efratom FRS, and one Datum LPRO. (I have two more LPROs but don't have
the mating connector on
I am just finishing my promised stability and phase noise measurements
on a batch of inexpensive Rb standards; I hope to publish the results
tomorrow evening.
In the meantime, I've looked at two of the FE-5680s and their phase
noise is significantly worse than either the Efratom FRS or the
On 2/7/2012 4:30 PM, Attila Kinali wrote:
On Tue, 07 Feb 2012 16:15:44 -0500
Mike Naruta AA8Ka...@comcast.net wrote:
On 02/07/2012 03:59 PM, Attila Kinali wrote:
while TV and radio uses 75R. (there was once a reason
for this, but i don't know it).
A 4:1 balun takes old 300 ohm twinlead to
Sorry for the cross-post, but I know this is of interest to some folks
on the HPSDR (high performance software defined radio) list, and I
suspect it may be helpful for some time-nuts as well.
The important message first: the little PicoPSU switching power
supplies that plug directly into an
; it just took the extra battery voltage to put them over
the edge).
John
Poul-Henning Kamp said the following on 02/04/2012 03:02 PM:
In message4f2d8b77.6040...@febo.com, John Ackermann N8UR writes:
The important message first: the little PicoPSU switching power
supplies that plug directly
Someone earlier today made the point that for all the talk about the FEI rubes,
there hasn't been any real performance info posted. That prodded me to start
an experiment I've been meaning to do for a while. I have samples of all three
of the common telco Rb standards -- Efratom FRS, Datum
There've been numerous threads on the Gnuradio mailing list about code
to receive GPS using the Ettus Research USRP hardware. I don't know
whether anyone has actually made it work, but it appears that it's been
the subject of quite a few academic projects.
John
On 2/1/2012 4:28 AM,
Tom Van Baak said the following on 01/26/2012 08:24 PM:
google for Space Weather Effects on GPS
there's a presentaton by Thomas Bogdan at the Space Weather Prediction
Center that gives you some numbers to work with.
10s of meters effects aren't unusual.
There's a wonderful example of GPS
the following on 01/25/2012 11:57 AM:
John,
How about these on EBay, Item : 110803140186
Cheap and plenty in stock.
I've just ordered 4 to experiment with.
Rob Kimberley
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of John Ackermann
Several years ago eBay offered some nice amplifier blocks that went up
to 500 MHz with about 10dB gain and 25dBm maximum output.
The part number on the unit is Harris 0130-211013, but they were sold as
Qbit 512.
I got a couple back then, and would now like to find two or three more
to use
Didier, check the HPSDR Janus baseband interface and related bits. It's a very
good ADC on a board designed with time-nuttish care and can do up 192ksps. The
downside is that it doesn't have a soundcard interface; the upside is that the
hardware and SDR software that alkmto it are all open
I think you have to define better, though. A GPSDRbO will have better
holdover performance (e.g., stability when the GPS signal goes away)
than one using an OCXO, but the OCXO is quite likely to have better
short term stability than the Rb.
If holdover isn't an issue, you need to find the
The TADD-3 output circuit with 3 74AC04 output stages paralleled is
stolen from Tom Clark's design in the original TAC GPS interface board.
The 47 ohm resistors aren't intended as back terminations; if you
assume a low output impedance at the chip, the three resistors are
effectively in
Hi Bill --
Normally, they do close the loop at the end of the trip by comparing the
traveling standard again with the home reference. In the quartz days, you
would use the difference to determine the daily drift over the length of the
trip (assuming the oscillator didn't get bumped too hard)
Kevin Rosenberg said the following on 01/07/2012 02:02 PM:
TAPR told me last year that the kit discontinuance was due to the Maxim RF
amplifiers becoming unavailable. I believe the T1-X65 transformers [1]
I just bought from Mini-circuits are similar or identical to the
transformer mentioned in
I am looking for a readily available (from Home Depot or other local
source) insulating material to use in a chassis that's housing a
sensitive OCXO. My goal is just to slow down any external thermal
transients so the oven loop has time to react gracefully.
I'm thinking of something in sheet
On 1/6/2012 2:54 PM, Chris Albertson wrote:
Can you put something that uses power inside an insulated box? I'd
think it might over heat.
Thanks, all, for the numerous and helpful responses!
To answer Chris' question, putting insulation all the way around the
oscillator might cause problems
On 1/6/2012 4:14 PM, Rick Karlquist wrote:
Before making this into a science project, consider this data
point: We converted the oscillator in a 10811 to run in mode
B at 10.95 MHz. The tempco in mode B is about 30 ppm per degree
C. Needless to say, the converted 10811 was extremely
On 1/5/2012 12:33 AM, John Miles wrote:
Grab the latest release from www.miles.io/timelab/readme.htm if you like --
it will acquire from the TSC 5125A for as many hours/days as the TSC's
Ethernet connection will stay up. (Which sometimes isn't very long.)
TimeLab generates its
Tom Van Baak said the following on 01/05/2012 02:27 PM:
John, could you expand on your comment about the ethernet connection?
I have seen random instances where the TSC seems to lose its TCP/IP
settings, but so far it's never happened during a measurement run, so
has been annoying but
Tom Van Baak said the following on 01/05/2012 02:27 PM:
I see this on the TSC 5120 but not the 5110. Same for you? When
in single DDS mode the 5110 phase is absolute. But when in the
dual DDS mode the raw phase output is scaled by B/A frequency,
which is displayed at the lower right side of the
On 12/14/2011 2:29 PM, shali...@gmail.com wrote:
Another small thing I miss is that a liter of water weighs a kg (under reference
conditions, I forgot what that was :). Then the specific weight of various materials only
has to be known by their density (ratio of specific weight compared to
Hi George --
You can feed frequency data into Stable32, but the documentation doesn't
clearly explain that you need to scale the readings into fractional
frequency using the scaling function in the File/Open dialog. To get
fractional frequency, you divide the results by the nominal
Not to take anything away from Paul's design, but if you have to buy the
box new, for three bucks more you can get a complete 10.7 MHz LPF with
BNC connectors from MiniCircuits (Model BLP-10.7+, $32.95). They also
have quite a few other useful cutoff frequencies -- 1.9 MHz, 5 MHz, 30
MHz,
TAPR has been out of stock for a while on the FatPPS pulse stretcher
(designed to allow a computer serial port to catch the very short PPS
signal that some time sources provide).
I'm happy to announce that we've done another production run and the
FatPPS is now back in stock. There's more
If the problem is only harmonics (cleaning up a square wave), a simple
LC low pass filter with a cutoff midway between the fundamental and
second harmonic might be a better choice because it minimizes the
tempco-related phase shift that either a high Q filter, or one with a
cutoff near the
We're working on getting another run going. Don't have a timeframe yet but
hopefully Real Soon Now.
John
On Oct 17, 2011, at 4:25 PM, Bill Dailey docdai...@gmail.com wrote:
Anyone know where to get one?
--
Doc
Bill Dailey
KXØO
controller on the antenna? Maybe that
should be my next test.
ws
**
from John Ackermann N8UR
I did some very rough measurements last summer with. Run of LMR-400 that was
laying on the roof in the hot Georgia sun.
Using a network analyzer to ping the cable I found the day vs
On Oct 7, 2011, at 3:32 PM, John Miles jmi...@pop.net wrote:
Intuitively, I don't believe a GPSDO can outperform an HP 5071A-era clock
over periods greater than a few hours. But it may be reasonable to
benchmark 5061A-class standards with a good GPSDO setup. We really need
some more data
In that test I was just capturing the ADEV table from the TSC-5120 so don't
have raw phase data.
I'm curious where you got the noise data for the TBolt gps engine -- that's far
better than I've seen quoted before. The Trimble data sheet that I found specs
the system PPS accuracy at 20
, but it doesn't
completely change the headers. I was misremembering.
John
On Oct 5, 2011, at 11:02 AM, Scott Newell new...@cei.net wrote:
At 07:09 AM 10/5/2011, John Ackermann N8UR wrote:
The mailing list system resends messages rather than just relaying them.
List messages won't show details
See my other message for more details, but the spammers often use a two-step
approach: (1) harvest address lists from the web, from compromised machines,
etc., and (2) send those addresses, along with the payload, off to the botnets
who then send the actual email. That gives
The owner of the list doesn't really care all that much about top vs.
bottom posting.
The owner of the list really just wants people to think about the list
charter before posting: time-nuts is a low volume, high SNR list for
the discussion of precise time and frequency measurement and
Folks (on both sides of the political aisle), we're getting way off charter
here. Lightsquared has been discussed on the list in multiple threads ad
infinitum so let's give it a rest unless/until there's some actual news.
Everyone, please keep in mind that time-nuts has over 1,000 subscribers
to the meter
reading, i.e. are they 1:1?
If there's a power supply then watch it's output voltage as the input is
brought up and at some point the output voltage will stabilize.
How about some photos?
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.End2PartyGovernment.com/
John Ackermann N8UR
Years ago I found an interesting box at a hamfest. It's from Frequency
Electronics and is labeled as a model FE-6018A Precision Frequency
Synthesizer.
It has an FE-10A 5 MHz frequency standard, and several internal
filter/mixer/other stuff modules. In addition to a 5 MHz output, it has
the
The blue labels just barely visible behind the control panel in the
close-up pictures look an awful lot like actual Sulzer labels. I wonder
if instead of being licensed it was actually OEM'd and they just
replaced the front panel with a purpose-built one.
John
On 8/25/2011 12:23 PM,
Just a note on the 8165: the primary output is from a decent quality
OCXO that's in an FLL (not PLL) circuit. The basic idea is that there
is a counter with a 1000 second gate time generated from (I think) a 10
MHz crystal that is tightly locked to WWVB with a very short time
constant.
I'm not sure if there's been other data posted, but a few years ago I
did phase noise measurements of the 8140T as well as HP 5087A and
TADD-1. That info is at
http://www.febo.com/pages/amplifier_phase_noise/
I got my hands on a tub full of 8140Ts but don't have the 8140 driver.
However,
Thomas, Dan, Magnus, Graham --
Thanks for the replies!
This is an interesting example of no two oscillators are the same.
I certainly expected that there would be aging and retrace on a cold
oscillator, but I started both Z3801As almost simultaneously and within
about 12 hours unit #1 had
I'm getting my two trusty Z3801As up and running after 18 months of
downtime and a 500 mile move. Unit #1 came up just fine.
Unit #2 has been running for about 18 hours and is working OK except
that the health status is showing an EFC error. The EFC value is above
1e6 (currently 1014166)
On 5/11/2011 10:20 AM, Dan Rae wrote:
On 5/10/2011 11:21 PM, Robert Atkinson wrote:
Hi Bob,
Apart from video distribution amplifiers (possibly modified, don't
ignore VGA ones, they have 3 analog channels -replace the 15 Hi-D with
BNC's) There is the TAPR TADD-1
On 5/11/2011 12:29 PM, Kevin Rosenberg wrote:
On May 11, 2011, at 8:25 AM, John Ackermann N8UR wrote:
Yes, unfortunately the MAX477 line driver chip that we used in the TADD-1 has
become unobtanium, and there's no drop-in replacement.
I'm (very slowly) working on a new distribution amp
Ed, I've thought about moving my 10 - 20 MHz unit as well. At one
point, I contacted PTS and they confirmed that the unit could be
modified by changing the filter module(s) -- not sure if there was more
than one. They quoted a couple of hundred dollars to make the change,
so I didn't pursue
I wonder if it's smart enough to have a sanity check to determine
whether the line frequency is 50 vs. 60 Hz?
BTW -- I have an Ecodrive watch, but it's radio controlled (as well as
solar charging), so haven't seen any reference to this setting method
before.
John
On 4/20/2011 10:13
Thanks, all, for the suggestions. I'm playing with WinOncore12 at the
moment -- for some reason I'm not able to get the M12+ receiver into
NMEA mode so VisualGPS isn't usable.
I'll fuss more with NMEA mode this weekend, but is there any magic for
the ioformat switch? I've used the command
, then there is no NMEA mode...
HTH,
Regards,
Jean-Louis
- Original Message - From: John Ackermann N8UR j...@febo.com
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Thursday, April 14, 2011 3:35 PM
Subject: Re: [time-nuts] GPS position averaging software?
Thanks, all
Just got a pair of GPS antennas on the roof and I'm interested in both
getting as accurate a position survey as I can, and in comparing the
performance of the two antennas -- one is a choke ring, the other a
Motorola Timing2000. I'm using an M12+ receiver.
I have TAC32 but am interested in
A couple of years ago I picked up a surplus Aeroantenna choke-ring GPS
antenna that I think was intended for surveying use. I finally got it
installed today and noticed that it has an arrow on the bottom
indicating that the antenna should be oriented with the arrow facing north.
I'm trying
Dave, I haven't seen an actual Manson standard, but I do recall that one
was listed in an ancient Tucker catalog (from the early 80s). I'm just
now unpacking my library after our move, and should soon uncover that
catalog if I still have it. Let me know if you'd like me to scan the
Manson
On 3/4/2011 12:22 PM, Dan Rae wrote:
Does anyone know if there is a planned or upcoming replacement for the
Tapr TADD-1?
We're working on a very high performance distribution amplifier that
will replace the TADD-1 and also be available in a single-channel
version for isolation/buffer amp
Here's a measurement we did a few years ago on the HP 58535A:
http://www.febo.com/pages/hp_gps_splitter/port_1_hp_58535a_two_port_amp.png
John
On 3/4/2011 1:31 PM, Bob Camp wrote:
Hi
Ok, now it's pretty obvious the RF world near your GPS will be changing a *lot*
in the near future.
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