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.
_______________________________________________
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.
