Hello G,
As far as i know, the dynamic range of these dongles is not suitable. 60
dB may be nice for playing arround but if you want to have a real RX for
weak signal detection, something serious which is running 24/7, like
Gary's grabber, you better spend the time and a bit of money and build
something with 100 dB dynamic range. Or, if you don't like building your
own stuff, buy some ready to use equipment, which is however just half
of the hobby, in my opinion ;-)
But designs covering a whole band (VLF/LF/MF) are up to date i find. Not
the SSB and dial stuff.
73, Stefan
Am 16.08.2015 18:48, schrieb Graham:
Thanks Stefan,
Gary sent a copy of his cct , Im wondering what one of the
usb dongles would make of it , pre-amp and band pass filters ...
73-G,
--------------------------------------------------
From: "DK7FC" <[email protected]>
Sent: Saturday, August 15, 2015 9:50 PM
To: <[email protected]>
Subject: Re: LF: Some LF again
Hi G,
No, i've made to many modifications from time to time. There is no up
to date schematic.
But, it is a typical design. A suitable band pass filter, impedance
converter matching to a SBL-3 mixer. The LO is 125 kHz, down-divided
by a CMOS 4060 and a 4 MHz xtal. Then an IF-LPF. That's all. You may
need an additional amp stage, depending on the incoming signal level...
73, Stefan
Am 15.08.2015 21:16, schrieb Graham:
Hi Stefan
Do you have a link to the CCT for the soundcard Rx ?
Tnx-G
http://myweb.tiscali.co.uk/wgtaylor/136SCRX.jpg
--------------------------------------------------
From: "DK7FC" <[email protected]>
Sent: Saturday, August 15, 2015 6:18 PM
To: <[email protected]>
Subject: LF: Some LF again
Hi LF,
I'm back there is WSPR-15 for some time. The power is reduced by 4
dB, unfortunately.
Maybe someone can catch a trace anyway :-)
73, Stefan/DK7FC
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