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Old December 7th 03, 11:41 PM
Jim Shaffer, Jr.
 
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On 6 Dec 2003 20:37:27 -0800, (RHF) wrote:

It requires a 12kHz IF to interface to a PC Soundcard. However I may
just take the more usual 450 ish and mix it down to 12 kHz.


They are talking about a 1st Stage 12kHz IF Band Width at a 455kHz IF
Frequency.
- - - NOT a 12kHz IF Frequency.


If it was at 455 kHz you wouldn't be able to decode it with a sound card.

Certainly it's not normal to have a 12 kHz IF on an analog receiver, but I don't
know why you couldn't call a 12 kHz output an IF since you're feeding it to what
is in effect another demodulator stage. The makers of the TenTec RX-320 and the
WinRadio G303 call it an IF. The TenTec precedes DRM, in fact -- the 12 kHz
signal is fed to an internal DSP for demodulation in conventional modes, the
output jack for DRM was added later. The WinRadio G303 was conceived after the
DRM specifications were released, but also uses the sound card to digitally
demodulate analog modes.