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Hi Graham,
About 74 kHz reception: I recently discovered that a Lenovo 'X61s'
netbook, bought cheaply at a rally, supports true 192 kHz sampling
with the onboard 'soundcard' (once one discovers where to
configure that in the swamped windows 7 system control, or
wherever they decided to put the soundcard control dialog today.
IIRC it was "Properties of Microphone", translated from german
into english).
Indeed the usable 'audio' range covers a few Hz to 96 kHz ! This
would allow direct reception on 74 kHz, and also using DCF77, MSF,
or similar time signal transmitters as reference for the sample
rate correction... SL could translate down into the audible
range, and downsample to 48 or 24 kS/second, before sending the
converted signal to other applications.
Anyway it would be much easier if the "hard coded frequency range"
would simply be removed from the original Opera software, and
completely leave it to the human operator to enter the frequency
range in a simple input field.
73,
Wolf .
Am 29.12.2013 18:56, schrieb Graham:
Thanks Wolf,
With the 8K signals out side the Op decoder , some
users wanted to monitor the test , but needed a way of
changing the qrg slightly to match ,
The other thing , that occurred to me , was the other
75 K stations , may have a TA chance using Op4H , +6 dB gain
over op1H in the 'window' time , may be 1 run or 2 max
? ... recovering the 8K audio may be a problem , my
ra6790gm has a locked bfo range of +/- 19KHz or so ,
but , for normal ssb-rx , then a shift up from 1500
would be needed [ may even catch Bob on 4H hihi]
73-G,
Sent: Sunday, December 29, 2013 1:25 PM
Subject: Re: LF: VLF exciter / signal generation
in Spectrum Lab
Hello Graham,
Am 29.12.2013 14:04, schrieb Graham:
Wolf,
Q How to configure SL as audio frequency changer ?
say 1500 Hz to 8 KHz , or , 8100 to 8200 etc
how is the set up ?
The easiest way is using the 'narrowband filter', which can also
shift frequencies.
Start by selecting 'Quick Settings' in the menu, then 'Other
amateur radio modes', 'Narrow CW filter with adjustable xyz'. You
can see the filter's passband on the main frequency scale, along
with the 'zero beat' indicator similar to a web sdr. Grab the
passband widh the mouse and move it to the 'source' frequency
range. Alternatively, enter the frequency shift in numeric form on
the filter control panel. Details:
http://www.qsl.net/dl4yhf/speclab/filters.htm#filter_controls_on_main_freq_scale
will SL appeared as a sound source ?
It can, but unfortunately only as an ASIO device. Microsoft's
ever-changing driver model is so utterly complex that I gave up
writing my own 'multimedia driver'. Also I didn't feel like
re-inventing the wheel for XP, Vista, Win7, Win8, and
whatever-comes-next... :o) Thus the easiest (??) method would be
to use Virtual Audio Cable.
The more complex (but VAC-less) way, if ASIO is supported by the
audio-receiving application, is decribed in the 'Audio I/O'
manual:
http://www.qsl.net/dl4yhf/AudioIO/AudioIO_Manual.pdf
The relevant chapter would be "Installation of in_AudioIO.dll as
an ASIO device".
Now back to the soldering iron..
73, Wolf .
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