Hello Scott,
Since today i am running a QRSS-600 window on my grabber. We can do a
lot of tests if you want, i have the time and fun for it :-) Just tell
me if you want to try other frequency sectors. I plan to transmit on my
200m vertical antenna in some weeks. This may give us a chance, at least
for a reception :-)
As you know i am using SpecLab for the grabber. It includes a function
that makes it possible to compensate the soundcard drift if a reference
signal is applied. My VLF grabber is "locked" to GPS by a GPS module
with a 10 kHz output (you can see the peak on the wide band window at
http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber.html
(scroll down)). So the frequency is stable in a range of at least 1 mHz.
Thus it was possible to receive DF6NM's "N" transmission (transmitting
"N" in DFCW-3000!). The frequency was absolutely correct, no offset, no
drift.
On my LF grabber the 10 kHz signal is injected too and compensates the
soundcards drift but there is a cristal oscillator to convert the 137
kHz in the audio range. This oscillator is not yet GPS disciplined and
so the drift might be some 10 mHz during usual temperature changes. This
will be done soon by applying a PLL...
I have recorded/displayed the harmonic line at 130 kHz of the 10 kHz
rectangular signal of the GPS module that appears at 5 kHz after mixing
with the unstable 125 kHz signal (1 MHz oscillator, divided by 8),
locked to another reference. I saw that the drift remains in a range of
< 100 mHz currently.
So, if you want to try DFCW-600 or DFCW-240 and your carrier is GPS
disciplined, you may give it a try. There is still no signal on the
LF/600 window but i will correct that in about one hour :-)
Best 73 and wish fun with your impressing TX setup!
CU, Stefan/DK7FC
Am 09.09.2010 21:20, schrieb Scott Tilley:
Hi Stefan
Now for useful comment...
Peter G3PLX did some work on a detection scheme known as 'clicklock.'
Using software with the algorithm would allow you to detect a GPS
locked signal way into the noise and well beyond what undisciplined
detection systems would.
If you have a GPS receiver with a 1PPS output you're almost there...
You need some software, http://www.qsl.net/zl1bpu/SOFT/click.htm and a
simple interface to inject the clicks into you RX audio. The software
does the rest. I wrote some similar software but this version is far
more robust and has more user interface options.
My TX is GPS disciplined and I can change my phase in 11.25 degree
steps and create any old phase modulated signal I want, let me dream
something up.... Peter and I did tests back when I had a peanut
whistle for an antenna with no success. Now this may be possible...
This would most likely be the path to detecting an amateur signal over
the pole on the brutal VE7/EU path.
Let me know if you're game for some tests.
73 Scott
VE7TIL
On 9/9/2010 6:24 PM, mal hamilton wrote:
Strange request, cu next year with a report, QSB could be a problem 3
months
dip and 4.5 months up.
This is probably a wind up, the man cannot be serious
!!!!!!!!!!!!!!!!!!!!
g3kev
----- Original Message -----
From:<[email protected]>
To:<[email protected]>
Sent: Thursday, September 09, 2010 7:01 PM
Subject: Re: LF: Request for modification of Argo Time base
Is it possible to add a "QRSS-600" ...
>you are asking for an FFT of giant length... :-)
Alberto - this version should also include on pop-up calendar so
that the
operator would know which day of the month to look for his complete
call
sign ;-)
WEB - "The VE7SL Radio Notebook": http://members.shaw.ca/ve7sl
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