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- Newsgroups: rec.models.rc
- Path: sparky!uunet!storcon!paulm
- From: paulm@storcon (Paul Moreau)
- Subject: Re: AM vs FM AGAIN? - Have Mercy
- Message-ID: <BuBDxn.84@storcon>
- Sender: paulm@storcon (Paul Moreau)
- Organization: Storage Concepts, Inc.
- References: <1992Aug17.172709.28039@usceast.cs.scarolina.edu> <1992Sep5.042114.3993@nntpd.lkg.dec.com> <1992Sep7.235638.7688@ccu.umanitoba.ca>
- Date: Wed, 9 Sep 1992 14:08:10 GMT
- Lines: 58
-
-
- In article <1992Sep7.235638.7688@ccu.umanitoba.ca>, umteghts@ccu.umanitoba.ca (david teghtsoonian) writes:
- |> In <1992Sep5.042114.3993@nntpd.lkg.dec.com> fisher@kay.enet.dec.com (kay::fisher) writes:
- |>
- |> >> Dual conversion on an AM? I thought that dual conversion was impossible/
- |> >> useless on an AM receiver because of the method of detecting an AM signal.
- |> >> Besides, I've yet to see an AM receiver that had 'Dual Conversion' on it.
- |> >>
- |> >>--
- |> >> _____________________________________________________________
- |> >> - * _______ _~; -
- |> >> - Paul Moreau | =_= / -
- |> >> - Sr. Diagnostics Software Eng. \ USA / -
- |> >> - Irvine, California ---> *-_ ___ / -
- |> >> - UUCP: ..!uunet!storcon!paulm \/ \\ -
- |> >> _____________________________________________________________
- |>
- |> >Well - I didn't want to answer till I was sure.
- |> >Check out Model Aviation October 1992 issue page 160.
- |> >The add for Kraft Midwest Inc. shows a dual conversion AM receiver.
- |>
- |> >Bye --+--
- |> >Kay R. Fisher |
- |> >---------------O---------------
- |> >################################################################################
- |>
- |>
- |> Actually, dual or single conversion superheterodyne receivers work equally
- |> well using AM, FM, PCM or just about any other modulation technique. Dual
- |> conversion, without getting too technical, takes place BEFORE the demodulation
- |> stage of the receiver, so the modulation scheme used is irrelevant. Dual
- |> conversion makes the receiver less susceptable to interference from other
- |> signals as well as reducing the spurious emissions (interference to other
- |> people's receivers) produced by your receiver. The modulation scheme used
- |> also has an impact on the receiver's susceptabilty to interference. AM is
- |> naturally more susceptable to interference than FM or PCM and probabley
- |> stands to gain the most from using a dual conversion receiver.
- |>
- |> -Curt
-
- Thank you for clearing that up for me. I stand corrected.
-
- BTW: PCM can use either FM or AM modulation. Both AM and the standard FM
- use PPM. Pulse Code Modulation and Pulse Proportional Modulation.
- (or is that Pulse Position Modulation)?
-
- Most PCM's use FM signal modulation be cause of the inherent noise
- immunity. If it used AM and was in a noisy environment then it
- would spend more time in failsafe or hold than operating.
- --
- _____________________________________________________________
- - * _______ _~; -
- - Paul Moreau | =_= / -
- - Sr. Diagnostics Software Eng. \ USA / -
- - Irvine, California ---> *-_ ___ / -
- - UUCP: ..!uunet!storcon!paulm \/ \\ -
- _____________________________________________________________
-
-