Re: Doppler DF

Article View: sci.electronics.basics

Article #168

Back to sci.electronics.basics Previous Next

#168

From: Rod Speed
Date: Thu, 21 Feb 2002 04:51

23 lines
2029 bytes

Echidna <echidna@hotmail.com> wrote in message
news:l9Yc8.7$dV1.23422@paloalto-snr1.gtei.net...

> I am wanting to play with some radio direction finding and am wanting to
> know either some useful web sites, ideas and possibly useful books.

You get a ton of hits using 'doppler df' in google.

> I had a look through a HAM radio operators book on RDF and the one
> that looks most interesting to me is the Doppler DF as it gives a bearing
> on the current direction you are heading.  However, when I looked the
> aerials that usually go with the units they are the size that you stick on
> your car roof rather than a small aerial set.

Thats basically due to the way doppler DF works, the antenna array
size depends on the frequency of what you are doing the DF on signal
wise, and that size is related to the wavelength of that frequency.

In other words you'll only get a small size with the higher frequencys.

> Even the ones with small stubby aerials
> required a large ground plane.  Why?

Technical Details

Message-ID: <a51umv$3v2ui$1@ID-69072.news.dfncis.de>

Path:

arc1-ca.pugleaf.net!archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!fu-berlin.de!uni-berlin.de!066.gri0101.gri.iprimus.net.AU!not-for-mail

References: <l9Yc8.7$dV1.23422@paloalto-snr1.gtei.net>

Show Full Headers

Complete Article Headers

X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103407,a2cc16cd794ad992
X-Google-Attributes: gid103407,public
X-Google-Thread: 111d0a,a2cc16cd794ad992
X-Google-Attributes: gid111d0a,public
X-Google-ArrivalTime: 2002-02-20 20:57:09 PST
Path: arc1-ca.pugleaf.net!archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!fu-berlin.de!uni-berlin.de!066.gri0101.gri.iprimus.net.AU!not-for-mail
From: "Rod Speed" <rod_speed@yahoo.com>
Newsgroups: sci.electronics.basics,aus.electronics
Subject: Re: Doppler DF
Date: Thu, 21 Feb 2002 15:51:57 +1100
Lines: 26
Message-ID: <a51umv$3v2ui$1@ID-69072.news.dfncis.de>
References: <l9Yc8.7$dV1.23422@paloalto-snr1.gtei.net>
NNTP-Posting-Host: 066.gri0101.gri.iprimus.net.au (203.134.92.66)
X-Trace: fu-berlin.de 1014267424 4164562 203.134.92.66 (16 [69072])
X-Priority: 3
X-MSMail-Priority: Normal
X-Newsreader: Microsoft Outlook Express 5.50.4133.2400
X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400

Reply to Parent Message