For our UK readers...
GPS Jamming exercises announced by OFCOM
Dates: 22 to 26 September 2008.
Times: Short periods of three minutes up to three hours per day between
08:00 and 17:00 hrs.
Location: Sennybridge Training Area - N52° 01.181' W003° 36.684'
Contact (during jamming exercise only) -
There are usually some BNC bulkhead connectors on eBay that terminate
in SMA/SMB/SMC pigtails, which are great for panel mounting.
Not directly related to this design, but it made me wonder about something.
If you are building a multiple output system and channel phase to channel phase
was
Bob Paddock wrote:
There are usually some BNC bulkhead connectors on eBay that terminate
in SMA/SMB/SMC pigtails, which are great for panel mounting.
Not directly related to this design, but it made me wonder about something.
If you are building a multiple output system and channel
Well - I have lots and lots of raw numbers, and no really good way of plottinng
it. I'm hardly a linux guru, but would gnuplot be a suitable tool for graphing
data like the snipper below?
374741 -0.5 0.00 0.7314587 32.10 0 130 18.2 158 4.0 12 1.8 132 3.2 157 9.0 152
5.8 138 12.0 133 6.2
Tom,
Gnuplot is perfectly suitable for stuff like this. You just need to
describe what you want to graph, and set some bounds and ranges,
output type, etc...
Somewhere on my home server, is a backup of it's predecessor, I have
a Gnuplot script suitable for running out of cron as a daily
I recently obtained a FEI FE-5680A Rb standard Revision: B.
After powering it up 'out of the box', a lock @ 50.25505.. MHz was obtained
within
a few minutes, confirmed by measuring the lock indicator on pin 3 of J1 and
listening to the signal on my FT 857 receiver. Nice to hear it sweeping
before
At 05.10 11/07/2008, Bill wrote:
What have you done with Life using modern computers?
Er... not so modern, but... I wrote a Life program in Z80 assembler
to exercise the emulator on an HP 64000A development system... it was
in 1981 :-)
Life was ideated by J.H. Conway in 1970. See
In message [EMAIL PROTECTED], Marco IK1ODO -2
writes:
Life was ideated by J.H. Conway in 1970. See
http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life . Fascinating
(to me) as it was 27 years ago. Sorry for the OT!
Actually, the idea is much older (WWII), and like so much else,
comes from
I used a package recently called ploticus:
http://ploticus.sourceforge.net/doc/welcome.html
It has some builtin prefabs for doing date/time based plots that made it
pretty easy to use.
GnuPlot is the granddaddy of all plotting packages. I'm sure it could do the
job.
johnea
On Fri, Jul 11,
If I remember correctly, the 1PPS pulse width is only about 100 ns.
There are two possibilities:
1) you can't see the pulse height properly at the very low sweep rate
you're using. Trigger on it at a much higher sweep rate, crank up the
intensity on your scope, and look carefully.
2) the
Magnus Danielson:
1) Please could you clarify what you're proposing with the series resistors?
I get the idea about 10nF in parallel with R24-R26, though I'm not sure what
the benefit is? Those MUX control pins are going to sit pretty hard on 5V
or pulled down to ground.
2) You said:
I am
Hello,
I have a question regarding the temperature reading in the Thunderbolt Monitor
program of the Trimble Thunderbolt GPSDO. Is this the temperature of the board
or the temperature of the crystal?
Related to this: does it help to put the Thunderbolt in an isolated box or is
this an
Hello,
a question regarding the Allan Deviation of the Thunderbolt.
the curve at
http://www.leapsecond.com/pages/gpsdo/
gives a deviation of 1.5e-12 at tau=1s
whereas from the Trimble datasheet:
http://trl.trimble.com/docushare/dsweb/Get/Document-10015/
at tau=1s, the deviation is 9e-10 ...
, foo-loop goes to
foo/loopstats.20080711 and foo-loop-1 goes to foo/loopstats.20080710 Then
the gnuplot include files just refer to foo-loop and foo-oop-1 When making
graphs, I ignore the first column and add a 24 hour offset on one file to the
plot command.
That generally works OK for looking
From: David C. Partridge [EMAIL PROTECTED]
Subject: Re: [time-nuts] Frequency divider design critique request
Date: Fri, 11 Jul 2008 18:41:52 +0100
Message-ID: [EMAIL PROTECTED]
Hej David,
Magnus Danielson:
1) Please could you clarify what you're proposing with the series resistors?
I get
Hello,
a question regarding the Allan Deviation of the Thunderbolt.
the curve at
http://www.leapsecond.com/pages/gpsdo/
gives a deviation of 1.5e-12 at tau=1s
whereas from the Trimble datasheet:
http://trl.trimble.com/docushare/dsweb/Get/Document-10015/
at tau=1s, the deviation is
At 10:41 AM 7/11/2008, David C. Partridge wrote:
M
All,
CPLD - wassat? OK, OK I have some idea, but that's about all I know.
Anyway these are probably BGA stuff which I couldn't hope to hand solder
anyway - it's enough of a stretch for me to think of hand soldering this SMT
board.
CPLD - small
Jim Lux wrote:
At 10:41 AM 7/11/2008, David C. Partridge wrote:
M
All,
CPLD - wassat? OK, OK I have some idea, but that's about all I know.
Anyway these are probably BGA stuff which I couldn't hope to hand solder
anyway - it's enough of a stretch for me to think of hand soldering this SMT
Well, I don't really have much time right now, but I started working on a
Monitor for the Trimble ThunderBolt (and other GPS receivers). With 3 TBs
here, it would make sense.
Here is where I am at the moment:
http://www.ko4bb.com/Timing/GPSMonitor/
The idea is to decode the TSIP packets
There've been some interesting conversations about useful TF hardware
gadgets lately. I'm personally very interested in the 10 MHz divider
project (as I've been working, very slowly, on a similar project with
several people on the list) and the Tbolt monitor projects.
Let me mention, then,
In a message dated 11/07/2008 21:48:44 GMT Daylight Time, [EMAIL PROTECTED]
writes:
If there is enough interest, it would not be very hard or expensive to make
a small PWB for the processor (the DIP version would be easier to solder),
the voltage regulators, the pot (to adjust screen
The temperature is the electronics temperature. When I put the cover on my
red-boxed unit, the temperature went up about 8 C. This would not have
happened if them temp was inside the thermostatically controlled oven.
Hello Dieder,
I posted the source to a ThunderBolt data dumper a while back. It has a full
TSIP parser in it. John Miles also posted his tweaks to make it win-32
compatible. Since then I have combined the two and tweaked it some here and
there.
I also have a new program that does graphing
The Thunderbolt data sheet says that the unit requires 25mA at 12V. That spec
would imply it is for a unit without an OCXO since the oven heater draws
considerable current from the 12V power supply. But then, the data sheet says
it draws 15 watts cold, 10 watts steady state. That implies
I believe the Allan variance graph in Trimble's data sheet was taken before
Selective Availability was turned off. I'm not sure what impact this would
have; I wouldn't expect any at all at tau 100s.
A pronounced hump in the ADEV plot could suggest that the disciplining loop
is underdamped.
Found it, I'll look at it. I remember that thread now. I have been a little
preoccupied lately, hence the need for a diversion in the form of writing
software. However, it plays games with my short term memory :-)
Thanks
Didier
-Original Message-
From: [EMAIL PROTECTED]
Hi group,
Sorry that it's a bit off-topic but I know that there are a lot of
people on this list who also own these beasts and other HP gear.
For the repair of my 8662A signal generator I'm looking for a 1826-0372
amplifier. Anybody has one or knows about an available substitute?
Sincerely,
Monitoring the crystal temperature would probably be extremely boring. I
would expect it to be absolutely stable, as far as the internal TB
temperature monitor is capable of displaying it.
Monitoring the electronics temperature is useful because it relates to the
ambient and allows you to plot
The Thunderbolt data sheet says that the unit requires 25mA at
12V. That spec would imply it is for a unit without an OCXO
since the oven heater draws considerable current from the 12V
power supply. But then, the data sheet says it draws 15 watts
cold, 10 watts steady state. That implies
My Thunerbolt is sitting on the floor. It is covered by an upside down
cardboard box. This added mayby 1 C to the temperature reading. It hovers
around 40C (when my unit in the red metal box was open, it was around 32C).
My temperature plot typically shows a sine wave shape with around
In the beforetimes, I built several precision temperature systems using the
Analog Devices AD537 voltage-to-frequency converter. This chip has an on board
temperature sensor and makes a very nice precision thermometer. Due to its
size and thermal mass it is good for fairly slow response
At 03:37 PM 7/11/2008, Didier Juges wrote:
On the other hand, I think it would be very well advised to place the unit
in a quiet area with minimal temperature changes, like you would do to keep
a good bottle of wine.
I knew that putting my Z8301 in the wine locker in the garage was a
good idea.
A strange anomaly shows up occasionally in the temperature plot. You
occasionally see a 100 millidegree instantaneous positive spike in the
data. The temperature then decays over 30 seconds back to the
original curve. This occurs on all of my units. They are all
different revisions with
Magnus Danielson wrote:
Hej David,
Magnus Danielson:
1) Please could you clarify what you're proposing with the series resistors?
I get the idea about 10nF in parallel with R24-R26, though I'm not sure what
the benefit is? Those MUX control pins are going to sit pretty hard on 5V
or
In a message dated 12/07/2008 00:14:13 GMT Daylight Time, [EMAIL PROTECTED]
writes:
when my unit in the red metal box was open, it was around 32C
--
I'm intrigued by this and similar earlier references.
I've only seen Thunderbolts in gold coloured aluminium boxes, where did
You can see a picture of the red box unit in the Thunderbolt data sheet:
http://trl.trimble.com/docushare/dsweb/Get/Document-10015/
I got mine off of Ebay. It has a builit in telecom style power supply that
takes from 32-72 volts. It came with a input power cable that ored two input
supplies
In a message dated 12/07/2008 01:01:27 GMT Daylight Time, [EMAIL PROTECTED]
writes:
You can see a picture of the red box unit in the Thunderbolt data sheet:
_http://trl.trimble.com/docushare/dsweb/Get/Document-10015/_
(http://trl.trimble.com/docushare/dsweb/Get/Document-10015/)
I was one of those who was lucky enough to get my order in for a
Thunderbolt before
the order machine was shut down. Now I am wondering what my status is in
the queue
for shipping.
Does anyone know how many thunderbolt units there are still to be tested
and to be shipped?
I don't want to
I was one of those who was lucky enough to get my order in for a
Thunderbolt before the order machine was shut down. Now I am
And it will open up again when/if a new large batch materializes
from the telecom salvage firm. So don't despair if you missed out
last month.
wondering what my
Magnus
A minimalist approach for the 5MHz to 10MHz doubler could use a full
wave (diode, BJT or JFET) doubler followed by a series tuned 5MHz shunt
trap to minimise the 5MHz content in the output.
If the doubler components were perfectly matched (unlikely) the
fundamental trap could be
David Partridge wrote:
CPLD - wassat? OK, OK I have some idea, but that's about all I know.
Anyway these are probably BGA stuff which I couldn't hope to hand solder
anyway
Many CPLD's are leaded. Only the high-pin count CPLD/FPGA's are BGA.
Chris Hoover,
Christopher, per favor.
You
Well, the good news is (if you buy one of these) is that the worst
that can happen is that you unwrap all that 2nd oven junk and
you are left with a 10811 for $50. I remember when they were
designing that double oven 10811. There are so many things
wrong with the design that I wouldn't know
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