I've put some info about the TNS-BUF isolation amplifier at:
http://febo.com/pages/TNS-BUF/
I'll work on adding to this page as I can, and in the next few days will
post some information to the list about how we'll put a group order
together.
John
_
I don't mean to hijack the thread, but may be able to avoid Bob having
to reinvent the wheel. A few years ago I built up the PCB for a high
isolation, low noise buffer amp based on a design by Bruce Griffiths.
The board is all set for production; I just ran out of time.
The "TNS-BUF" works ex
ohn- you are possibly thinking of the Icom IC- 22S.(among others!)
> DaveB, NZ
>
>
> - Original Message - From: "John Ackermann N8UR"
> To: "Tom Van Baak" ; "Discussion of precise time and
> frequency measurement"
> Sent: Thursday, Apri
om my own hardcopy HPJ collection are here:
http://www.leapsecond.com/hpj/
For example, the 79-step ADEV program is here:
http://www.leapsecond.com/hpj/v22n4/v22n4p10.jpg
Finally, do not miss HP AN116 "Precision Frequency Measurements":
http://www.hpmemoryproject.org/an/pdf/an_116.pdf
/t
I was browsing through the HP Journal archives and came across the May,
1969 issue, dedicated to the new 5360A Computing Counter -- "An
Electronic Counter for the 1970s!"
I don't recall hearing much about these in time-nuts lore. I can guess
from the Journal articles that it was a beast to ke
When I looked at the Wenzel amps, they were extremely low noise, but the
isolation was nothing to write home about.
On 03/26/2016 08:20 PM, John Miles wrote:
I'm looking for off the shelf connectorized amplifiers with very good
reverse isolation for doing things like intermod measurements (e.
In light of this discussion, I'm taking a deep gulp to mention a project
that's finished but has been on my back burner for a while.
A few years ago I laid out a high isolation, low noise buffer amp based
on one of Bruce's cascaded-transistor designs. Isolation was measured
in excess of 100dB
On 3/24/2016 4:54 PM, Bob Camp wrote:
Would make a good target device. It’s based on the AKM 5397 So might some Janus
boards.
They are based on the earlier(?) AKM 5394. The QA401 has the advantage of a
nice box
and full USB isolation (ground loops are a pain). It also has drivers and all
the
I'd be willing to assist with board layout if someone wanted to make
this into a real project (e.g., fully developed schematic). TAPR might
be talked into supplying at least bare boards; we'd have to get a sense
of demand before committing to a full kit or assembled unit.
John
On 3/24/20
There's a plot of the unlocked sweep of an FE-5690 at the bottom of
http://febo.com/pages/oscillators/rubes/
I think the LPRO is pretty similar.
John
On 3/22/2016 2:02 PM, Hal Murray wrote:
time-nuts@febo.com said:
are you sure your LPRO actually locks? You say you have measured 10.000 MHz
b
I don't need it myself, but that looks an awful lot like a Sulzer 2.5 or 5.
On 3/21/2016 9:01 AM, Bert Kehren via time-nuts wrote:
Attached is an old Dual Oven Flask high performance OCXO. I do not have the
flask any more (broke) and no more info but if some one recognizes it and
wants it for
Hi Attila --
I have some stuff that does ADEV and similar calculations and shoves the
results into plots using the Grace plotting tool. It's basically a perl
script using some document formatting templates and a couple of shell
scripts for control. I use it to automagically create web pages
Hi Joe --
If I was allowed only to keep two pieces of test equipment, one would be
my Fluke 77 and the other my 8920! It does pretty much everything you
need for AF and RF below 1GHz, though nothing quite as well as the
specialized gear.
The high stability oscillator is very good. I've onl
Thanks, Warren. That's a very nice solution! I have a unit on the way from
another time-nut, so I should be set.
I'm pretty sure the problem with the old unit is just aging as I watched the
EFC creep for months toward the limit. I bought two units at the same time
(long, long ago) and though
I have a Z3801A whose oscillator has aged out of correction range, and
thus throws an EFC alarm.
Anyone have a still-in-range double-oven HP10811 from a unit that died
for another reason? If so, I'd be happy to acquire it.
(I tried disassembling one of the double-oven 10811s years ago and fo
I'm not in front of the manual or the board right now, but if you look
at the layout you will see two pairs of pads at the output end of the
board. If you look at the way the pads are physically arranged along
with the schematic, you'll see that you can either connect to two of the
pads to get
Tom Van Baak has developed dividers based on simple PIC chips that will
produce 1 PPS from several input frequencies. These dividers have
remarkably low jitter, down in the couple-of-picosecond range, and are
very simple.
I've implemented life support circuitry around two versions of Tom's
c
Apologies, all -- this wasn't meant for the list. Thanks to another
time-nut, though, I now have the info!
Best,
John
On 12/19/2015 12:53 PM, John Ackermann N8UR wrote:
Hi Ian --
Happy holidays!
A few years ago I got some of the breakout board kits you did for the
FE-5680A. Th
Hi Ian --
Happy holidays!
A few years ago I got some of the breakout board kits you did for the
FE-5680A. They've finally risen to the top of my "to assemble pile." :-)
Looking for the schematic and any assembly info you might have available
-- I only have the boards and parts but can't fin
There is a gotcha in the TSC phase data... the architecture introduces a
deliberate phase offset to the phase data so you will always gain (or
lose) phase over time. Hook both inputs to the same source, and you'll
still have a slope in the output data (and the slope and intercept will
be diffe
I've had a chance to see Jeff in action at Morehead, and what he and the
team there are doing is really incredible -- and inspirational. He's
built a hands-on electronic and mechanical shop, mainly out of surplus
stuff, that gives the students tremendous practical experience, while
they are pu
A long, long time ago I captured a solar flare while monitoring GPS
signal strength:
http://febo.com/pages/gps_solar_flare/
There was a very significant drop in signal level. Unfortunately, I
wasn't able to capture any phase data that corresponded to the event.
John
On 9/30/2015 3:15
to allow for true stripline layout.
(b) there are 50 ohm termination resistors on all the non-selected
inputs, so you're not switching from an open circuit condition.
John
On 9/30/2015 9:17 AM, John Ackermann N8UR wrote:
Thanks, Tom. These sorts of projects are why I disappear fro
e of cable or load changes do you see any noise or
disturbance on the first or second reading after you change the switches? Also,
what's the rated lifetime of the switches?
Thanks,
/tvb
- Original Message -
From: "John Ackermann N8UR"
To: "Discussion of precise t
Every so often, I hijack the list to do some shameless self-promotion
when I think it would be of interest to the 'nuts community.
I've spent the last several months developing a computer-controlled
relay switch system. The impetus was failure of the old HP 59307A GPIB
switches in my PPS meas
I may be remembering incorrectly, but I thought that you only need the
GPS for initial sync; after that shouldn't the processor be able to
maintain the sequence without new GPS input, so long as the timer clock
doesn't drift too badly? From a known starting point, the modulation
pattern should
This is profoundly cool, Paul! Thanks so much for this work.
I'm not making any promises, but I hope to lay out a PCB for the DBM
section and will make the gerbers available. If there's enough
interest, we might be able to do a group PCB order. Contact me off-line
about that.
John
On 9/2
I just did some measurements on a Sulzer 5 MHz OCXO that dates from the
early '60s. Not only is the performance quite amazing, but there's a
surprise: it's not on the frequency you'd expect, and it may have some
historical interest.
Details at http://blog.febo.com/wp/?p=17
(I'm playing with
I have one each of the HP and NI USB units, and have both sets of libs
installed on the same machine. I seem to have no trouble using either. But
the size of each company's download is absurd! So,ething like 800MB between
them.
> On Sep 11, 2015, at 5:08 PM, Tommy phone wrote:
>
> Have nev
Attached is a frequency plot of my 5065A vs. GPS (via PPS) over about 6
months. Note the changed freq and slope between about MJD 57205 and
57235. That correlates to the month we were out of town on vacation,
with the air conditioning set about 6 degrees higher than normal.
(There was probabl
I'd be interested in that as well... mine is out of amplitude cal as well.
> On Aug 11, 2015, at 4:23 PM, Richard Moore wrote:
>
> Does anyone know the procedure for resetting the output level constants in
> these generators? The manuals I’ve found are silent on this, but it was
> obviously do
If anyone is really interested in an SDR WWVB receiver project, TAPR has
a fairly large quantity of boards left over from a previous project that
use a very high performance 192ksample sound card chip (AK5394) in a
carefully laid-out design with no filtering (I believe the inputs are
also DC co
In the past, a number of kind time-nuts have offered to assist with
issues related to list administration. I could now use some of that help.
For a long time, I have been trying to find and resolve the cause of
persistent delays in some email messages routed through the list server
at febo.co
Hi Corby -- it just so happens that I've been plotting my 5065A (super) against
several sources since last February -- about 130 days of data so far.
Here's the data against a GPSDO as reference:
http://febo.com/pages/plots/chronos/hp5065a-z3805a.html
This is based on PPS comparisons.
John
> O
Hi Ed --
For standard PC hardware, 250ns is way under the interrupt granularity
of the computer, and will never be noticed. Some specialized
configurations (https://www.febo.com/pages/soekris/) have timer
resolution to a few hundred nanoseconds, but that takes hacking.
I know there have bee
Referencing the conversation about squaring circuits, I realized the T2-Mini
board (intended as a tiny PIC-based PPS divider) can be repurposed into a very
nice squarer.
It has a slightly modified version of the Wenzel squarer and by simply
installing a jumper wire instead of the PIC chip (pin
Just put the GPS antenna, receiver, battery, and a low power RF
transmitter modulated by the PPS (wide bandwidth = fast edge time) on
the turntable, then use an appropriate receiver to demodulate the PPS
and feed it to the rest of the system. Put the RX antenna directly
above (or below) the tu
Wenzel has published the schematic of an excellent squaring circuit. I
don't have the URL for their version handy, but I used it (with a couple
of mods) in the TADD-2 and TADD-2 Mini designs. You can see the
schematic in the T2-Mini users guide at
http://www.tapr.org/~n8ur/T2_Mini_Manual.pdf.
Among my group of ham project-building friends, the motto is "There is no
problem so big or complicated that it cannot be over-engineered."
> On Apr 13, 2015, at 5:03 PM, Richard (Rick) Karlquist
> wrote:
>
>
>
>> On 4/13/2015 12:14 PM, Magnus Danielson wrote:
>>
>> Oh yes. Some people say
One comment on the parallel AC gate approach. It may not be directly
applicable to Martyn's issue, but there is a common confusion about the
value of the summing resistors.
Per Tom Clark, who came up with the idea, they are *not* intended to
provide a near-end line termination to 50 ohms, but
I'm working on a measurement setup using an HP 5334 TIC to capture single-shot
PPS data that I log via GPIB.
For each reading I clear the counter, then poll using SRQ until data is ready.
The measurement cycle seems to always take between 1.5 and 2 seconds, even if
the start/stop signals arriv
mp
in the antenna vs. 6dB in the splitter.
On 02/08/2015 08:29 AM, John Ackermann N8UR wrote:
I think that the surplus HP/Agilent GPS splitters may have an SAW
filter. If so, measuring the delay of one of those could yield at least
an approximation.
I may have that data laying around; I'll
I think that the surplus HP/Agilent GPS splitters may have an SAW
filter. If so, measuring the delay of one of those could yield at least
an approximation.
I may have that data laying around; I'll do some digging.
John
On 02/08/2015 05:11 AM, Attila Kinali wrote:
On Sat, 7 Feb 2015 10:
Hi Bill --
I've been quietly observing this thread because I don't have the
knowledge to talk about the doubler circuit generally.
But the crystal filter is, in my opinion, a really bad idea. Any
resonator is ultimately a thermometer, and a high-Q device on the output
of the circuit is goin
All -- Ulrich has been having some AOL-related problems with the mailing
list. Anyone who wants to contact him about the SMIQ manual should
contact him directly rather than via the list.
Thanks,
John
On 12/10/2014 10:50 AM, paul swed wrote:
Ulrich
I had asked for the manual.
Also let me
Thanks for the kind words, Dick. :-)
However, a couple of notes on the TADD-1 bandpass filter:
1. I *don't* recommend installing it unless there is a good reason. As
others have noted, any tuned circuit is a thermometer and will degrade
ADEV performance. Other than the original test unit, I
Yes, I'm pleased to report that with help from a couple of 'nuts who
pointed me in the right direction, I was able to make a configuration
change that seems to have solved the base64 encoding problem.
I think we've now restored all the pre-update functionality.
John
On 09/17/2014 12:58 PM, B
We've been on the new version of Mailman for a couple of weeks now. The
main reason for the update was to work around the "DMARC" adoption by
Yahoo, AOL, and other large ISPs that broke the mailing list model.
That seems to be working now. I'll spare the technical details (you can
read about it
A little late to the conversation, but there are some relatively low
cost (few hundred dollar) PC-based lightning detector products
available. I run one that's a PCI card with Windows software that
generates a map and statistics that upload to my web page once per minute:
http://www.febo.com/
That's the output freq of the "standard output" on the front panel. The RX is
60 kHz only.
John
On Jun 25, 2013, at 10:27 PM, Perry Sandeen wrote:
> List, There are several Spectracom 8164 receiver available on Ebay.
>
> My question: on the front panel bank of frequency selection switches,
There was definitely a delay -- I saw it on my own message last evening.
I have done some performance tuning on the mail server that might (or
might not...) make a difference.
The new server we put on line back in January certainly has enough
horsepower, so hopefully tweaking is all it will t
I'm not aware of any specific server issues here (the configuration is fairly
stock Debian with Mailman and Postfix) but there can be delays due to the
vagaries of the internet and there are interactions that can cause delays for
some folks and not others.
I'll keep an eye on things to see if I
I didn't look at this initially because I thought it was a reference to
the (s)NTP time setting program for Windows that came, I think, from a
company called Dimension4. I wonder if there is any connection?
John
On 5/9/2013 3:46 PM, Bob Camp wrote:
Hi
A little poking at the web site:
Hi Tom --
Are you talking about capture time limits, or minimum tau? I've never
encountered any capture time limits in TimeLab and have done out to 30 days.
However, one thing I have noticed with the 5120A ethernet using my own
capture software is that the data flow will sometimes stop for s
Hi Tim --
Welcome! The easiest way to search the time-nuts list is to use Google
and add the "site:febo.com" tag -- that will bring up hits in the list
archive (as well as anything on my web site that might be pertinent).
John
On 4/30/2013 1:49 PM, Tim Bastian wrote:
Hi all,
I'm a ti
Hi All --
Some of you know that I've been working on a very high performance
buffer amplifier in both a single channel version and a 6 channel
version that will replace the TADD-1, which TAPR discontinued because
the MAX477 op-amp is no longer available.
Unfortunately life and health and a f
Jason, a few months ago I was able to build a FreeBSD 9 system using
standard NTP. It involved a lot of pain, a lot of help from PHK, and a
lot of handwaving, but in the end it worked. I'm happy to share config
info if you'd like -- contact me off list.
John
On 4/19/2013 9:50 AM, Jason
Ulrich, I'm on the run right now, but I've done measurements of the HP 5087,
TADD-1, Spectracom 8140-series line amp, and a new protoype ULN buffer amp.
I'll post the links later today.
John
On Mar 14, 2013, at 6:59 AM, "Ulrich Bangert" wrote:
> Gentlemen,
>
> although it has been discussed
John Miles' most excellent TimeLab software should be able to do what
you want: http://www.miles.io/TimeLab/beta.htm
John
On 2/25/2013 10:39 AM, Dan Rae wrote:
I am working on 400 - 500 MHz DDS clocks for an amateur radio project
and would like to record over gpib and plot the relative frequ
And this (very interesting) thread brings up the question of measurement
methods. Some time ago I searched around and didn't find much on a
standard way to measure noise on low voltage DC supplies.
John
On 1/31/2013 11:36 AM, Bob Camp wrote:
Hi
I think the comparison of PSD on a power
If there's interest and we can agree on a charter, I would be happy to
create a "measuring-nuts" (or similar) list at febo.com.
If so, I'd like the charter to be along the lines of "high
signal-to-noise ratio discussion at the serious-amateur level of
scientific measurement tools and technique
Hi Corby -- I've often thought of the idea of mixing two 5 MHz sources in a DBM
and using the resulting 10 MHz, so I'm really curious to see how this works
out. Seems like injection locking is the most likely problem you'd have to
deal with.
Let us know how this goes!
John
On Dec 28, 2012,
The Clock-Block is a clock generator that is useful if you want to replace the
computer's onboard crystal clock with an external high-stability source. For
example, you can configure it to take a 10 MHz input from a GPSDO and create a
14.318182 MHz output to replace the crystal in a PC that use
And folks, please respect Brooks' privacy -- remember that this list is
archived in many places on the web.
John
paul swed said the following on 12/21/2012 04:06 PM:
Kind of defocusing here. I think the thread is about possibly helping to
release the shera v4.02 software. Several folks app
Magnus Danielson said the following on 12/20/2012 05:29 PM:
On 12/20/2012 10:19 PM, John Ackermann N8UR wrote:
TimeLab can talk directly to the 512x boxes via ethernet. I've also
written some Linux scripts to capture both phase data and graphs from
the 5120; happy to share with anyone
TimeLab can talk directly to the 512x boxes via ethernet. I've also
written some Linux scripts to capture both phase data and graphs from
the 5120; happy to share with anyone who'd like them (but TimeLab is a
whole lot easier in most cases).
John
On 12/20/2012 4:09 PM, Bob Camp wrote:
Hi
Y
On Dec 11, 2012, at 6:57 PM, Magnus Danielson
wrote:
> Tom,
>
> On 12/12/2012 12:44 AM, Tom Van Baak wrote:
>>> I think that the TBolt's schematic(s) are sort of HolyGrail for TimeNuts.
>>
>> Some French time nuts told us they already have one. It's very nice.
>
> Would you be able to share?
On 12/10/2012 7:10 AM, David Kirkby wrote:
On 10 December 2012 09:24, David C. Partridge
wrote:
Related to time-nuttery as astonomical observation was used for time-keeping
until C20.
Sir Patrick Moore, the great amateur astonomer died yesterday at the age of 89.
Although considered an amat
I don't have an internal search engine on the server, but most folks just do a
google search using the "site:febo.com" option and that seems to work well.
John
On Dec 8, 2012, at 11:24 AM, "Mike Garvey" wrote:
> Is there a way to search the Archive?
>
> I can find the archive, but there see
On 12/6/2012 4:35 PM, Charles P. Steinmetz wrote:
From my perspective, the most interesting development would be an offer
by someone with a very well equipped lab to test any DIY GPSDO with a
consistent protocol and publish the results. That way, we could all see
how the various approaches com
On Nov 30, 2012, at 7:42 PM, John Ackermann N8UR wrote:
> In this case, you're not looking for the RTC but rather the clock that drives
> the COU
Read "CPU". Stupid iPad keyboard.
___
time-nuts mailing list -- time-nuts@febo.c
On Nov 30, 2012, at 7:10 PM, Sarah White wrote:
> On 11/30/2012 6:30 PM, Eric Garner wrote:
>> the actual RTC on modern (Intel based) PC's is driven from a standard
>> 32,768 Hz crystal attached to the PCH. some of them are in incredibly small
>> packages now instead of the old tuning fork-in-a-c
In this case, you're not looking for the RTC but rather the clock that drives
the COU, which is what drives the system clock. On most systems, the RTC is
read only at startup and is not used once the system is running.
John
On Nov 30, 2012, at 6:30 PM, Eric Garner wrote:
> the actual RTC on
Sadly, no. Different number and it looks like pin-out as well.
On Nov 29, 2012, at 6:06 PM, Robert Atkinson wrote:
> Is that ADO27B op-amp module on the PCB the same one used in the degausser
> for the HP 5061 high performance tube?
>
> Robert G8RPI.
>
>
>
ing not to interchange the modules between the two
systems. There may be some value in reviewing the MFTS manual to see if
there's anything applicable to the MFS.
Ed
On 11/25/2012 10:15 AM, John Ackermann N8UR wrote:
At a recent hamfest, I picked up an interesting looking Efratom "
At a recent hamfest, I picked up an interesting looking Efratom "Made in
Germany" MFS modular frequency standard system. It's basically a GPS
disciplined FRK Rubidium with XO fail-over and a whole bunch of RF and
PPS outputs, in a *very* heavy box.
I've had a chance to play with it a bit and
A couple of weeks ago I posted about problems with my HP 10638A
degausser (that's used with the 5061 Cs units to remove residual
magnetism from the high-performance option tube).
My troubleshooting indicated that the problem was likely in the op-amp
that is used to generate an exponentially de
deleting the message and its attachments from your
> computer without keeping a copy. It is strictly forbidden to copy it or use
> it for any purpose or disclose its contents to any third party. Thank you.
>
>
>
>
>
>
> On Nov 14, 2012, at 8:13 PM, John Ackermann N8UR
Corby and Bert --
Count me in!
John
On Nov 19, 2012, at 3:15 PM, cdel...@juno.com wrote:
> As Bert mentioned once the amount if interest is established purchase
> details will post.
>
> We also will post a FAQ for this project.
>
> Thanks,
>
> Corby
> ___
Edgardo, the minimum sample rate in practice is determined by the noise floor
of the measurement system. I would suggest that you do a baseline test by
measuring the counter reference against itself with a tau0 (sample rate) of 1
second. You'll see a best-case result and from it you can determ
From what's been reported here, the mechanism isn't consumption of the
Rb, but rather deposition of material on inside of the bulb, reducing
its intensity, and that can sometimes be reversed by tricks that some
time-nuts have reported -- it's more of a maintenance rather than a
wear-out issue.
purpose or disclose its contents to any third party. Thank you.
On Nov 13, 2012, at 8:21 PM, John Ackermann N8UR wrote:
Hello Edgardo --
The T2-Mini uses a wide-range input circuit based on one that Wenzel published
with some modifications. It works with a square wave input (I've don
Hello Edgardo --
The T2-Mini uses a wide-range input circuit based on one that Wenzel published
with some modifications. It works with a square wave input (I've done some
limited testing) but I can't verify whether the input amplitude range will
extend as far on either the low or the high side
Joe, the question is whether the DDS spurs and noise on the FE-5680A are strong
enough to interfere with your measurements. I suspect that in the HF/VHF
range, you'd probably be OK, at UHF maybe dicey, at microwave probably not good
(assuming you're multiplying the Rb up).
I have phase noise m
Hi Magnus -- I was recently (within the last year) able to get the battery pack
in my 5P power supply rebuilt by the local Batteries Plus store. It took a few
weeks for them to order and obtain the cells, but they do seem to be available.
John
On Nov 1, 2012, at 4:51 PM, Magnus Danielson wrot
Thanks to all for the helpful replies.
At this point, I believe what happened is that the degausser isn't
working properly and that may have resulted in the tube being more
magnetized rather than less; no matter what I do, I am now getting lock
at about -5e11 -- which is not what it used to be
Since I recently got an HP Cs degausser (thanks, Stijn!), I though I'd
go through the whole setup routine for my 5061B/004 and see how close
the C-field-via-Zeeman setting would bring me to GPS-derived frequency.
It turned out to be an interesting and puzzling exercise.
This 5061 seems to be
-boun...@febo.com] On
Behalf Of John Ackermann N8UR
Sent: Saturday, October 27, 2012 09:06
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] 5061B ops manual without missing pages?
Does anyone have a copy of the 5061B ops manual that does not have pages
3-7 and 3-8 missing
Does anyone have a copy of the 5061B ops manual that does not have pages
3-7 and 3-8 missing? The copy at the Agilent site doesn't have those,
and they are the basic start-up instructions.
I am guessing that the steps are not much different than those in the
5061A manual (which I have), but i
Hi Edgardo --
One slightly frustrating thing about the 5065A is that its frequency
settability isn't as good as its short term stability. I believe the manual
says that the small divisions on the C-field counter dial are 2x10e12, and it's
hard to set closer than that.
A good 5065A is a remark
n deleting the message and its attachments from your computer
without keeping a copy. It is strictly forbidden to copy it or use it for any
purpose or disclose its contents to any third party. Thank you.
On Oct 14, 2012, at 8:23 AM, John Ackermann N8UR wrote:
On the unit I bought from fluk
On the unit I bought from fluke.l, with a "Samsung" label, there are two
serial ports. The bottom one is the control port and is definitely
RS-232. The top port has only three wires (TXD, RXD, SG) and I think is
used for some sort of monitoring.
I've been using Ulrich's "z38xx" software to m
Here's a link to a USNO paper that measured the tempco of three GPS
amplifiers: http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA490830
They found that amplifier filtering was the prime cause of tempco, and
the narrowest bandpass amplifier they looked at had a group delay range
of 4 nanoseconds over
Bob, check http://www.febo.com/pages/plots/ntp and see if the graphs
there would provide the info you need. They're based on using one NTP
server to monitor the offset of a number of other services and plotting
the results over time. If so, I'm happy to make the (*nix-based)
scripts available
Found the data on the splitters:
http://www.febo.com/pages/lab_documentation/gps_cable_delay/hp_gps_splitter/
My recollection was a bit off -- we saw about 22ns on the two-port 58535a and
about 15ns on the 8-port 58517A. I would guess the 4-port unit would be
similar.
Unfortunately, I haven't
We measured the delay on a couple of the splitters. I need to dig up the
results, but I think the delay is around 7ns in both the 2 and 8 port units,
and is pretty consistent port-to-port. I'll find the data and get it on the
pages at febo.com.
John
On Sep 30, 2012, at 2:51 AM, Christopher B
On 9/28/2012 12:10 PM, George Race wrote:
I have a good size offering of vintage electronic equipment that I would
like to get rid of, mostly 50's and 60's stuff from HP, Tek, Boonton,
Stoddart, ect.Is it permissible to post the listing here, along with
pictures, or is there another place tha
I know the WWVB news is something that's important and on-topic for this
group. However, with the discussions about zoning/regulations and the
creeping trend toward general political comment, I think it's time to
refocus.
Remember that there are 1200+ recipients of every time-nuts message, an
Paul, I have a couple of Spectracoms running and have pretty decent WWVB
signal strength here. I'd be happy to test the hack.
John
On 9/26/2012 1:32 PM, paul swed wrote:
I may have at least the spectracoms figured out. Its a hack and at least
using my homebrew wwvb psk encoder seems to w
"BVA" is an acronym for a French term that means something like
"improved aging". It's a unique type of crystal mount that reduces
mechanical stresses, and has been built into OCXOs by Oscilloquartz in
Switzerland.
A "Blue Top" is a Wenzel Associates ultra-low phase noise oscillator.
Wenzel
101 - 200 of 1042 matches
Mail list logo
