Isn't 433 MHz a common frequency for unlicensed emitters? It is entirely possible that the occupant of that vehicle was using one.
COrtland ====================== Original Message Follows ==================== >> Date: 17-Jun-98 02:09:23 MsgID: 1061-9447 ToID: 72146,373 From: Tim Haynes G-Net 701 3239 / >INTERNET:[email protected] Subj: Re: Emissions or not? Chrg: $0.00 Imp: Norm Sens: Std Receipt: No Parts: 1 Sender: [email protected] Received: from ruebert.ieee.org (ruebert.ieee.org [199.172.136.3]) by hil-img-1.compuserve.com (8.8.6/8.8.6/2.12) with ESMTP id FAA15450; Wed, 17 Jun 1998 05:09:19 -0400 (EDT) Received: by ruebert.ieee.org (8.8.8/8.8.8) id FAA17294 for emc-pstc-resent; Wed, 17 Jun 1998 05:07:14 -0400 (EDT) Disclose-Recipients: prohibited List-Post: [email protected] Date: Wed, 17 Jun 1998 09:57:21 +0100 (BST) From: Tim Haynes G-Net 701 3239 / 3455 <[email protected]> Subject: Re: Emissions or not? To: emc-pstc <[email protected]> Message-Id: <6621570917061998/A02205/PLANET/11C68A791500*@MHS> Autoforwarded: false Mime-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII Content-Transfer-Encoding: 7BIT Importance: normal Priority: normal Ua-Content-Id: 11C68A791500 X400-Mts-Identifier: [;6621570917061998/A02205/PLANET] Hop-Count: 2 Sender: [email protected] Precedence: bulk Reply-To: Tim Haynes G-Net 701 3239 / 3455 <[email protected]> X-Resent-To: Multiple Recipients <[email protected]> X-Listname: emc-pstc X-Info: Help requests to [email protected] X-Info: [Un]Subscribe requests to [email protected] X-Moderator-Address: [email protected] WoW! Replies! Rather than respond in person I acknowledge all replies with thanks and comment here. BTW the 144.8 MHz tx is 100W e.r.p. Reflections from the Green Italian car? Why not all the other cars? Over all the other days, weeks, years that I have been using these frequencies? Too much coincidence. I like the idea that it might be the radio receiver in the Italian car kicking out a spurious response. Fault on my receiver? NEVER! :-) Oh well - possibly, but why only in relation to this Italian car? Third harmonic? 144.8 x 3 = 434.4 + 3xdeviation... not equal 433.325 by a long way. BTW 3rd harmonic is neg 74dBc on my old HP 8566a. I think it rules out the rusty bolt syndrome as well. The idea that it is an alarm system (the "here I am - I've been stolen" type) is possible though the chances are pretty low - there are not too many users of that alarm system here in the UK. Resonating car...? Hmm....? Possibly but I streaches my imagination. Duff (Duff is UK slang for faulty/bad) electronics! Well - this was my first thought. Nice processor with lots of harmonics of clock frequencies and the subdivisions. Lots of switches changing the terminating impedance of the tracks (don't forget I am assuming a duff design). Now that really would modulate an incoming signal! Rating of the proposed causes? No I will let you all decide which is the most likely. Me? I am looking for a Green Italian car to experiment on. Oh, the make? I do't want to upset Fiat so I won't tell you......:-) Regards to all Tim ====================== End of Original Message =====================
