Path: archiver1.google.com!news1.google.com!sn-xit-02!supernews.com!newsfeed.di rect.ca!look.ca!news.maxwell.syr.edu!pln-e!spln!dex!extra.newsguy.com!newsp.new sguy.com!enews2 From: i...@intellisys.net (Brian Whatcott) Newsgroups: rec.boats.building Subject: Re: home made radar Date: Sun, 25 Nov 2001 01:03:34 GMT Organization: BWInc Lines: 60 Message-ID: <3c003eac.19639712@snews.intellisys.net> References: Reply-To: i...@intellisys.net NNTP-Posting-Host: p-329.newsdawg.com X-Newsreader: Forte Free Agent 1.21/32.243 On Mon, 19 Nov 2001 12:09:00 -0600, "Beepme" wrote: >Not that I aim to try, but are there any designs for building your own >radar? Here's how you could put together the most rudimentary radar. Its range would be laughable, and its directional sensing would be poor, but it would be a radar. Material List Collect an electronic ignition system from a salvage car. Arrange a pulser (could be an audio signal generator) to pulse at 1000 times a second. Find a tin can about 8 inches long, and 4 inches diameter. Find an aluminum sheet about 5 feet square. Find an old satellite dish. Construction Drill a hole in the sidewall of the tin can, half way up big enough to snugly fit a sparkplug. Remove the ground electrode. In the opposite wall of the can, solder a thick copper wire, so that it leaves a gap of 40 thou to the spark plug center electrode. Connect the audio oscillator, and ensure it triggers the ignition and lights up the spark plug continually. Rig the can, oscillator, and ignition about 2 feet away, and facing the aluminum sheet, stiffened with a plywood sheet stuck on the back. Phase I Radar. Connect a diode at the focus of the satellite dish and connect it by a short coax to an oscilloscope. Make sure the oscilloscope triggers with the audio oscillator. Rig the aluminum sheet and the satellite dish facing the same direction with the sheet infront of the dish, so as little energy as possible leaks back. Point the rig at a tall metal structure 250 feet away Connect the diode receiver to the highest gain input possible of the scope. Look for the small peak at 500 nanoseconds across the oscilloscope trace. Phase II Inject a microwave oscillator into the diode output, and feed the mix to a communications receiver tuned to 30 megs. Feed its output to the scope as before. Do let me know how it goes! :-) Brian W Brian Whatcott Altus, OK Eureka!