On 4/16/2013 1:55 AM, Jim Lux wrote: > On 4/15/13 10:22 PM, Jim Lux wrote: >> On 4/15/13 9:27 PM, Tom Van Baak wrote: >>> NIST SIM GPS common view pinwheel >> described in one of the NIST reports as an aperture coupled slot fed >> array that is better than a patch, but not as large and heavy as a choke >> ring. >> >> W. Kunysz, 2000, “High Performance GPS Pinwheel Antenna,” in >> Proceedings of the 2000 International Technical Meeting of the Satellite >> Division of the Institute of Navigation (ION GPS 2000), 19-22 September >> 2000, Salt Lake City, Utah, USA (ION, Alexandria, Virginia), pp. 2506-251 >> >> http://www.novatel.com/assets/Documents/Papers/GPS-704xWhitePaper.pdf >> Patented by Novatel & Pinwheel is a trademark >> >> >> Performance is almost as good as a choke ring but a heck of a lot >> smaller and lighter. >> > > of course, cake pans with 2-2.5 inch high walls are readily available. > > There's a Wilton cakepan set with 6",8" and 10" diameter pans with 3" > walls.. hmm, an inch between fins.. > > Oddly, the package shipping size is 12x12x2"... I wonder how they fit a > 3" high pan in a 2" thick box.. > > a real restaurant/pastry supply has a mindboggling variety of pans > > http://www.fantes.com/cake-pans-round.html > > every integer inch diameter from 4" to 18" and ditto for heights from 2" > to 4"... > > > People like those machined or cast choke rings because they're easier to > fabricate: Slap a block of aluminum in the lathe or milling machine, > push GO on the CNC, and stand back. > > Or for those with a taste for hot metal.. you could cast it with scrap > aluminum you've melted in the forge in your time nuts lab.. Turn those > empty beer cans into something useful. > > If you have a fancy multiaxis mill, you could probably do one of those > porcupine looking things. > > Or, if you have a swimming pool or pond, and some sheet aluminum, and > some suitable high explosives.. hydroforming is your friend. > > If you want true timenuts.. do the explosive hydroforming without a > mold/buck, and instead use precision timing of shaped charges. Finally, > a use for those krytron switches you found at the surplus place.
Thanks for that. The last bit of your post was really cute. I needed a good laugh :) I haven't posted much in a while, partly because I've been kinda bummed out by this list since I got the news about shera... There have been so many constant reminders of his passing and whatnot (multiple thread titles mentioning his legacy) I just have to ask though... cake pans? really? I can't imagine it would even be possible to modify a cake pan with enough accuracy to get a usable antenna. -- Sarah _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.