Hi
Of course the other option is to *finally* break down and buy a digital scope.
They've been out there for 20 years now.
Yes, I did indeed cross over to the dark side last week
Bob
On Feb 12, 2010, at 7:24 AM, Peter Vince wrote:
Hi Robert,
I put a dual-colour (red-green) LED
An
easy way to see the 10 microsecond pulse
On the
Tbolt is to use a pulse stretcher. I
Used this
circuit on the 25 microsecond wide
Pulse on
the HP Z3801 to add a true 1 second
pulse
indication to the front panel and also
output
the pulse through a 51 ohm resistor to
a BNC
on the back
I agree with many of these comments.
I guess LORAN C for timing will never die for me.
Now that I have the LORAN C simulator and it keeps the timing receivers
happy.
Granted the main reference is me but I have to say the HP5065 seems more
usable then wwvb. And very inexpensive compared to the
Actually pretty much what would happen if the same occurred now that
Loran C is turned off.
Tell me, how well does your GPS receiver work with Loran C? Do you
have a mapping Loran C receiver to take your GPS's place should it
be disabled? No one else does either.
-Chuck Harris
Sykes, Stephan
I still have a LORAN-C based navigation receiver in my plane. It is part of
a Northstar M2 system which uses Loran-C and GPS in a dual sensor mode.
Jeppesen stopped supporting the database for Northstar about a year ago and
now Loran-C is gone (haven't been flying since the shutdown to see if I
Greetings,
As a former user of Loran for aircraft navigation, I can safely say that
there is no reason to preserve the system.
The antenna required on an aircraft must be vertically polarized and of
significant length. The route from the US west coast to Hawaii had no
coverage in the middle
Well from what I have seen on posts I don't agree on LORAN C dying for Nav.
In particular there is a website that pilots use were they have been
bitching about the shut down. Will believe boaters are out there also.
But I think the real answer is that commercial pilots and Navigation
abandoned it
Message: 3
Date: Thu, 11 Feb 2010 23:02:30 -0500
From: Bob Camp li...@cq.nu
Subject: Re: [time-nuts] Advice on 10 MHz isolation/distribution
(Clay)
Hi
I suspect your noise spike can be cured by a series R-C to ground from the
junction of Q1 base, Q7 base and all the other stuff. Something
Hi Bob:
I have been studying digital scopes for some time and have the Rigol
DS1052E on the way.
http://www.prc68.com/I/RigolDS1052E.shtml
Rigol may make the low end scopes that are sold by Agilent. This model
goes for a little over $400 and gets excellent reviews (links on the
above web
True.
However, GPS is now so ubiquitous that if they put SA back on, Congress
would likely reverse the decision because of the outcry. GPS is a victim
of its own success.
FWIW,
-Jhn
===
What is going to happen if GPS has a problem, or if the US puts SA back
on? Now the only
I'm using a very bright blue LED and series resistor on the PPS output of my
thunderbolt and it's quite visible. It's not bright by any means, but it is
distracting to see out of the corner of my eye in the rack some days. I
like the dual color LED idea and think I'll make a similar connector
I got a DS1052E a few months ago and I'm quite happy with it. It's
great for looking at events
like this thread has been discussing (although am I the only person who
still owns a Radio Shack
logic probe from the 70's which would work just fine for detecting 1PPS??).
I won't be giving up my
About every GPSDO and GPS Timing receiver needs to do a self survey
before you use it. It has to know where it is in the world.
I would give it a master reset and then initiate a self survey.
Software controls and shows status of these type of commands. I use to
have a Jupiter receiver but
I use both a DS1052E and a couple of Tek scopes. I do like the
DS1052E and think it offers great value at 25% the price of a
comparable Tek. I love the long memory.
The Teks still feel more solid (in an accuracy/reliability/usability
sense). I noticed some trigger jitter on the DS1052E.
Henry
On Fri, Feb 12, 2010 at 07:29:39AM -0800, Peter Putnam wrote:
The antenna required on an aircraft must be vertically polarized and
of significant length. The route from the US west coast to Hawaii
had no coverage in the middle one-third of the route at night.
Coverage was even less during
On Thu, Feb 11, 2010 at 09:40:19PM -0800, Scott Burris wrote:
The GC-1000 keeps declaring the decoding to be invalid partway
through each minute.
Dean's synthetic WWV gets decoded perfectly and the display turns
out after 3 complete
minutes. But the 100Hz level in the synthetic sounds high
ashle...@aol.com wrote:
Hello. We built the 10mhz simple GPSDO from boards supplied by G3RUH.
(Using the Jupiter GPS receiver)
Questions:
Has anyone built one,
How well does it work
I haven't built one, but people who have say its performance is
comparable to commercial units. Check out
Hi
It's the one that Bruce posted earlier. Actually it showed up as a double post
for some odd reason. I opened the whole hybrid thing by referring to it.
Bob
On Feb 12, 2010, at 11:32 AM, life speed wrote:
Message: 3
Date: Thu, 11 Feb 2010 23:02:30 -0500
From: Bob Camp li...@cq.nu
Hi
I went with a used Tek TDS-380. I still live in a fantasy world where it's not
a scope if it doesn't say Tek on it :)
For a 15 year old scope the one I found seems to have pretty good performance.
I've used them enough at work that I knew anything much under 300 MHz and 2
GS/s would
The second recording still did not get the clock to sync.
So I tried an all up test, setting a WaveTek 288 signal generator to
5Mhz at -47db,
and used your audio to AM modulate the signal. This gets the AGC amp
back into
the picture. And it successfully decoded, saying 10:15 PST!
The
Majdi is correct. The budget report I saw showed that it was less to
upgrade than to decommission. It still doesn't make sense to rely on
only one system with the assumption that it won't break. I think in the
future that shutting down these site will be deemed a bad idea.
Steve KD2OM
I seem to not be accomplishing much isolation from output to input, as well as
output to output. Have I fumbled PSPICE somehow? For each simulation, Vac was
set separately, with V1=0.707V at the input, while V6=0V at the output (sim1).
Then V1=0V, and V6=0.01V (sim2).
Hi
There are a few differences between what you are simulating and the schematics
Bruce posted earlier. The collectors of the input stages (q1, q4 and q7) seem
have to come unglued from the bases of the output stages. The 95 ohm / 100 nf
roll off networks seem to have vanished from the
life speed wrote:
I seem to not be accomplishing much isolation from output to input, as well as
output to output. Have I fumbled PSPICE somehow? For each simulation, Vac was
set separately, with V1=0.707V at the input, while V6=0V at the output (sim1).
Then V1=0V, and V6=0.01V (sim2).
It does if you are a presidential suck up.
ie DHS head
Whats being saved is truly nothing.
But don't want to get on that soap box poor form.
On Fri, Feb 12, 2010 at 2:56 PM, Sykes, Stephan ssy...@harris.com wrote:
Majdi is correct. The budget report I saw showed that it was less to
upgrade
I'm about 680 mi. straight north of Fort Collins. About a year ago, I
got an Odetics WWV receiver that remembers the reception results for the
last 7 days. It tells me that the only time it can get a lock on WWV @
10 MHz is between about 0800 and 1800 hours. It never gets a signal in
the
Raj wrote:
While comparing a Rb FE5680 frequency reference with another RB or GPSDO I find
that tapping a Rb unit causes a sudden shift in the scope display meaning the
frequency has slightly shifted momentarily and locks back steadily with a phase
shift. This does not happen in another Rb
Raj,
Raj wrote:
Hi Stan,
I will explore this issue tomorrow, 20:00 here now. I was just going
through a boyish thrill of fiddling with a Sony ICF-S10Mk2 and the amazing
numbers of AM stations it picks up.. maybe it can be used at 60Khz.. for 10$ it
worth it !!
How about
Well, I just had a very odd experience today. I put the clock back in
service, but forgot to attach either the long wire antenna
or the extensible whip antenna. After a few minutes on 15Mhz in the
middle of the day, it picked up the time!
Attaching either the wire antenna or the whip made
GPS was and would still be useable with SA back on. And, the Coast Guard
still supports DGPS. I am no expert, but my GPS with SA on always beat my
use of a sextant.
John WA4WDL
--
From: b...@lysator.liu.se
Sent: Friday, February 12, 2010 6:46
The series RC to ground keeps the high frequency impedance seen by Q1
and Q7 low so that the base current noise which increases significantly
as the frequency approaches the ft of these transistors.
However such a series RC network does little to suppress the the rise
due to gain peaking.
A
Ed,
As I recall, the Heath receiver scanned three WWV frequencies (5, 10, and
15MHz?) and stopped on the one with the strongest signal. It would stay
there for a minute or two and move on if it couldn't hear the burst tone at
the top of the minute. If it heard the tone, it would stay put and try
A hog driver and time-nut; heck of a combination. I kept my feet on
the ground back in the '60s. but always had my spirits lifted when
Spooky showed up.
Heard you guys flew the wings off those planes. Boeing is replacing
all 242 wing sets for another 20 years of service.
Thanks for your
Hi
Since it's the input stage, it's likely the point most impacted by a higher
flicker noise part. That might make one want to look at alternatives.
Of course, it's not real clear that a super low noise amp is needed in this
case.
Bob
On Feb 12, 2010, at 8:46 PM, Bruce Griffiths wrote:
In the later version the input amplifier has a gain of 2x and the output
amplifiers have unity gain.
Whilst the reverse isolation (and output impedance) can be improved by
using a complementary symmetry emitter follower output stage, one has to
ask at that point is the performance gain worth
Hi
I have no data, but I believe that in the real application, the phase noise
would not be degraded by a good low noise RF op amp / buffer amp. About all you
can do for flicker noise data is to look at what they do supply and make an
guess based on how the noise rolls up over the range they
Thanks for the tips Magnus. I will open the unit and with gentle taps - see
what causes the problem.
Yes, I know that the frequency is programmable. The unit came from flyingbest
on Ebay and I see that three wires are connected from the 9 pin D to the inside
where the Tx/Rx connector. The
The only data available seems to be John Ackermann's measurements on the
TADD-1 distribution amp.
Unfortunately the opamp used is now obsolete or about to be.
Most recent discrete designs (not the HP5087 amplifiers) that I have
seen phase noise data for, have significantly lower flicker phase
Hi
There's also the throw everything at it approach.
Use something like common base stages for the input and op amps for the
outputs. Boost the level into the op amps and pad it at the outputs. You might
get what you need. More parts than a pure op amp design, more current. Likely
easier to
One issue with opamps may be the distortion as few of the high frequency
ones have distortion data for more than 2Vpp output.
Its can be little optimistic to scale from this if they plot distortion
vs input (or output level) or give IP2 and IP3 specs.
+10dB in 50 ohms requires 4V pp at the
Hi Ashley,
I've not built the G3RUH system but am aware of it and have used Jupiter GPSs
in the past. It would be useful,but not essential, to know exacty which
jjuiter model you have and what you want/need a GPSDO for.
In order of your questions,
Yes (not me)
OK, the 10kHz output makes the
What is going to happen if GPS has a problem, or if the US puts SA back
on? Now the only backup for navigation is a sextant.
Steve KD2OM
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bill Hawkins
Sent: Friday, February 12, 2010
Hi Steve,
What is going to happen if GPS has a problem, or if the US puts SA back
on? Now the only backup for navigation is a sextant.
Steve KD2OM
GPS _will_ (can) not get a serious problem as long as the US is at war.
Buy a Glonass receiver. (In a few years buy a Galileo/Gagan/GPS/Glonass
Hi Robert,
I put a dual-colour (red-green) LED in a BNC plug for just this
sort of purpose. No series resistor - the 50-ohm source impedance
limits the current nicely. With dual-colour, I can see both positive
and negative pulses. 100ms pulses are perfect, 10ms OK, 1ms are very
dim, but
In message 62026.87.227.52.225.1265975191.squir...@webmail.lysator.liu.se, bg
@lysator.liu.se writes:
GPS _will_ (can) not get a serious problem as long as the US is at war.
You mean just like Windows Vista has to be a success ?
It's always important to distinguish between hard facts and
There was a very informative article in Avionics Magazine last year summarising
the current status/vulnerabilities of the GPS constellation. It's well worth a
read.
http://avtoday.com/av/categories/military/35197.html
ian
What is going to happen if GPS has a problem, or if the US puts SA
Hi
I know it's a chicken and egg thing, but Loran-C died for navigation a while
back. The hardware simply isn't out there anymore. GPS could have died two
weeks ago and Loran-C would have not helped the navigation people. They don't
have the receivers in place. A backup that nobody is set up
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