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Hello,
I did just check the error on 11.904,761
KHz.
"
Effect of FFT settings with fs= 48.0000 kHz:
Width of
one FFT-bin: 423.855 uHz
Equiv. noise bandwidth: 635.783 uHz
Max freq
range: 8.91444 kHz .. 9.02556 kHz
FFT window time: 2359.296 s
Overlap from
scroll interval: 87.5 %
"
Error on 11.904,761 was -0.000,8 Hz
Did use GQD 22.1 Khz as Frequency Error Compensation in
Spectrum Lab.
Now, I did set that -0.0008 Hz error in the Offset
window.
I'll have to go to bed now.
Leaving the whistle spectrum observator on 8970 Hz
now.
Tnx for info !
73's Peter - PA1SDB
----- Original Message -----
Sent: Friday, March 23, 2012 10:23
PM
Subject: Re: LF: Now using Mini Whip here
on 8970 Hz in JO33kh, Appingedam
Hi Peter,
you could check the calibration later (after
the tests on 8.97 kHz) by temporarily switching the spectrogram's center
frequency to 11.904761 kHz (Russian 'Alpha' on that frequency is currently
active). It's not an ideal check because of the periodic signal ->
fence-like spectrum, but maybe the MSK transmitter on 20.9 kHz is not such an
ideal source. Anyway I will check it with the GPS-disciplined receiver, if FTA
is really 'spot on' frequency.
All the best,
Wolf
DL4YHF .
P.S. Suitable GPS receivers (with low jitter on the PPS
output) are quite affordable now. I use a Garmin GPS 18x LVC, which is
sensivite enough to be operated indoors. It used to be available (or still is)
at RS Components and other distributors. The receiver doesn't need to have a
10 kHz output; a low-jitter PPS output (one pulse per second) is sufficient to
compensate the soundcard's sampling rate continuously, and provide a very
accurate timestamp for other experiments.
Am 23.03.2012 23:00,
schrieb PA1SDB, Peter:
Hi Eddie,
I have set that 'Sampling rate detector" in
SL.
I use 20k9 FTA, the indicator is Green, I
have Enabled it.
What els have I to do ????
I use that Bandpas filter in the left Black
box.
8970 Hz center, 500 Hz width.
Spectrum on L2
FTT input size is 524288
Decimal input by is 216
That gives:
Effect of FFT settings with fs= 48.0000
kHz:
Width of one FFT-bin: 423.855 uHz
Equiv. noise bandwidth: 635.783
uHz
Max freq range: 8.91444 kHz .. 9.02556 kHz
FFT window time:
2359.296 s
Overlap from scroll interval: 87.5 %
I did not callibrate it somehow. On 30 meters
/ QRSS I use that time sign on 9996 KHz. I don't know how to
callibrate it on VLF.
I can't whistler that
stable :-)
That signal on 8.969,995 has a kund of fading. I
hope it's not something local.
Feel free to inform me if I do somnething totaly
wrong !
No hard feelings :-)
73's Peter - PA1SDB
----- Original Message -----
Sent: Friday, March 23, 2012 8:51
PM
Subject: Re: LF: Now using Mini Whip
here on 8970 Hz in JO33kh, Appingedam
Peter
Very good, how is your calibration? Henny is
on 8.97000 you have a line at 8.96995 if it stops at 23.00 that is when
Henny is QRT.
73 Eddie G3ZJO
On 23/03/2012 19:59,
PA1SDB, Peter wrote:
Hello all,
Today I did plant the "PA0RDT Mini-Whip" antenna
in the backyard at about 20 meters from the house and 4 meters above
ground level.
Last 2 week I was using 2 pasive loop antenna's
who where connected direct into the mike input.
That wasn't a succes...
I hope to see some results soon
:-)
Take a look at the links below. I
did start logging on Friday evening at about 19:00 UTC,
so perhaps I have to adjust contrast later.
73's, Peter - PA1SDB
QTH is Appingedam in JO33kh, in the very North-
East part of The
Netherlands.
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