Hi
If the WAAS sats were purpose designed to provide a high accuracy carrier, then
yes there are ways to do it. The fundamental design concept of a bent pipe is
that you don't do any of that. You do not care what's going through the bird,
it just maps the input frequencies to the output and
On 7/3/13 12:42 PM, Azelio Boriani wrote:
Sure about the bent pipe? If so it seems that much power is required
at the transmitting ground station...
Much equivalent power is required. If you have a 20 meter or so
antenna, it doesn't take much to get a pretty high EIRP.
Hi
On Jul 3, 2013, at 3:51 PM, jmfra...@cox.net wrote:
http://www.navipedia.net/index.php/WAAS_Signal_Structure
Doppler Shift: The Doppler shift, as perceived by a stationary user, on the
signal broadcast by WAAS GEOs is less than 40 meters per second (≈210 Hz at
L1)
So unless you can
On 7/3/13 2:21 PM, Dennis Ferguson wrote:
On 3 Jul, 2013, at 11:47 , Bob Camp li...@rtty.us wrote:
The pipe in this case is up on one frequency and down on another. The
conversion oscillator on satellite that's the weak link, no matter how good the
signal from the ground happens to be.
Dear Group:
I just got a VECTRON 5Mhz OCXO the model is 217-8422, does anyone have its
datasheet or PIN define? Thanks a lot.
Hui
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One possibility is that the CPU is getting turned off when idle to save
power. If that includes the stuff normally used for timekeeping, things
could get screwed up when it gets turned back on. It has to reset the
time, probably getting it from the RTC.
I don't think this is the case.
From: Chris Albertson
The computer itself and the NTP installation are OK because we can see it
syncing to other NTP servers. Likely you have a problem in the way the GPS
using is connected.
Some common errors is an inverted PPS, just flip it ad see if you gets
better, it is really hard to see
Oh for convenience. I need to patch ntpd to use linux pps (afaik) and on
other systems I successfully run gpsd with ntpd (read: low jitter).
Using gpsd with ntpd reduces the jitter versus just using ntpd by itself?
No I meant that running that combination is successfully because I see
low
On Wed, 03 Jul 2013 19:15:40 +
Brian Alsop als...@nc.rr.com wrote:
Apparently this modulation scheme is less prone to jammers.
There is is British station which jams east coast WWVB.
The way WWVB implements BPSK does not make it less prone to jammers
or noise. The idea, to get higher SNR
li...@rtty.us said:
If the WAAS sats were purpose designed to provide a high accuracy carrier,
then yes there are ways to do it. The fundamental design concept of a bent
pipe is that you don't do any of that. You do not care what's going through
the bird, it just maps the input frequencies to
I have the same model and the trigger settings are great for capturing those
tiny width PPS pulses.
I setup the trigger so I see the pulse in the middle of the screen and its
updated when the pulse occurs.
In a nutshell, as Chris mentioned, The trigger modes are excellent for time
nuts.
The
I just had a discussion about older spectrum analyser versus the new Rigol type
SA.
They are saying the Rigol is -80dBc.
Unfortunately I don't know what the specs of mine are.
Could someone help me out with some noise floor figures for the following?
* HP 8566A
* HP 8568B
*
Hi Ed,
On 07/02/2013 08:21 PM, ed breya wrote:
Here we go again - the first send didn't seem to get through. This is
the second attempt.
This talk of Costas loops reminded me of something I wanted to
investigate some day. I read somewhere a while back about carrier-phase
measurements, and
I just had a discussion about older spectrum analyser versus the new Rigol
type
SA.
They are saying the Rigol is -80dBc.
Unfortunately I don't know what the specs of mine are.
Could someone help me out with some noise floor figures for the following?
* HP 8566A
*
Please read the WWVB article on this. There is a whole section devoted
on how it can provide higher immunity to MSF. I don't think it a
false advertising claim.
www.jks.com/*wwvb*.pdf
Read the Fundamentals of the new protocol section.
Don't shoot the messenger please.
Brian
On 7/4/2013
Hi
The way doppler is corrected on a normal GPS is by having a large body of
orbital data for each sat measured by a bunch of stations and then processed
into the almanac. It's not a trivial process.
Since the doppler is in the hundred Hz or so range, I'd bet the conversion
oscillator was
Has anybody listened for LORAN in the US lately?
-John
=
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That works well for transponders with o LY one signal. On commercial
satellites, each transponder is shared among multiple signals, so that would
not work.
Didier
Jim Lux jim...@earthlink.net wrote:
On 7/3/13 2:21 PM, Dennis Ferguson wrote:
On 3 Jul, 2013, at 11:47 , Bob Camp li...@rtty.us
Hi
You really need to know a few things about the Rigol spec:
1) Is it simply a noise measure? If so, at what bandwidth and frequency (narrow
will always be lower)?
2) Is it a signal spec? If so with what signal level and settings? Does it
include / exclude IMD / harmonics?
3) Is it the spec
A few weeks ago I listened and there was something VERY weak (under 1 uV) from a
150 foot long wire. I've picked up 10+ mV a couple of months ago. Seems like
they're still doing testing.
On 7/4/2013 9:08 AM, J. Forster wrote:
Has anybody listened for LORAN in the US lately?
-John
John yes on and off every other week or so.
I hear nothing. But its pot luck and if I don't hear it I turn the radio
off. It would be easy to miss it.
Or perhaps the funding is not going to happen and it really is dead.
Regards
Paul
WB8TSL
On Thu, Jul 4, 2013 at 9:08 AM, J. Forster
Hi
At sub 1uV you may be getting one of the European chains.
Bob
On Jul 4, 2013, at 10:59 AM, Peter Gottlieb n...@verizon.net wrote:
A few weeks ago I listened and there was something VERY weak (under 1 uV)
from a 150 foot long wire. I've picked up 10+ mV a couple of months ago.
Seems
QST did a review of the Rigol DSA815-TG in the February 2013 issue, page 55.
The specs were determined to be as specified by Essco Calibration Labratories
of Chelmsford Mass. There is a copy here:
http://ed31.ref-union.org/Test_RIGOL_QST_February%202013.pdf
Bob - AE6RV
- Original
On Thu, 04 Jul 2013 07:59:59 -0500
briana als...@nc.rr.com wrote:
Please read the WWVB article on this. There is a whole section devoted
on how it can provide higher immunity to MSF. I don't think it a
false advertising claim.
www.jks.com/*wwvb*.pdf
Read the Fundamentals of the new
Which LORAN system are we talking about? I thought the US stopped
LORAN-C back in 2010 and eLORAN plans were cancelled. Are you talking
about the European eLORAN system?
John
On 7/4/2013 8:59 AM, Peter Gottlieb wrote:
A few weeks ago I listened and there was something VERY weak (under 1
uV)
Marki...
The noise floor spec to compare is the Displayed Average Noise Level (DANL).
This will usually be measured at the narrowest Resolution Bandwidth (RBW)
and Video Bandwidth (VBW) available. And possibly some trace averaging
thrown in and either the Average or Sampling Detector since this
On 7/4/13 7:33 AM, Didier Juges wrote:
That works well for transponders with o LY one signal. On commercial
satellites, each transponder is shared among multiple signals, so that would
not work.
Ah, yes.. if it's a linear transponder/translator..
Hi John:
How can I make a noise floor plot for my HP 4395A?
http://www.prc68.com/I/4395A.shtml
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
John Miles wrote:
I just had a discussion about older spectrum analyser versus the new Rigol
type
On 07/03/2013 11:59 AM, Attila Kinali wrote:
On Tue, 2 Jul 2013 17:06:47 -0400
jmfra...@cox.net wrote:
Valid concerns all. What I am building is a squaring circuit for
recovering the carrier from a WAAS GPS satellite. Granted there
is still some Doppler and other issues, but the accuracy
On 07/03/2013 02:29 PM, Bob Camp wrote:
Hi
There are two batches of GPS / WAAS sats up there:
1) The ones with numbers above 100 that are geosync and that only do WAAS
2) The ones with numbers= 32 that do nav. These are not geosync.
I believe the only ones with corrected / high stab clocks
Hi John:
How can I make a noise floor plot for my HP 4395A?
http://www.prc68.com/I/4395A.shtml
Those plots came from my old freeware app ( http://www.ke5fx.com/gpib/pn.htm
). It supports the 4396A but not the 4395A; see
http://www.ke5fx.com/4396a.gif for the baseline plot that someone sent
Hi
I believe the *code* is corrected, but the carrier frequency is not. Without
correction it's plenty close enough for any receiver that can handle a normal
GPS sat. The intended product is the code rather than the carrier. Even if
you tried to correct for doppler, it would only work for a
On 3 Jul, 2013, at 21:05 , Bob Camp li...@rtty.us wrote:
If the WAAS sats were purpose designed to provide a high accuracy carrier,
then yes there are ways to do it. The fundamental design concept of a bent
pipe is that you don't do any of that. You do not care what's going through
the
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