[aprssig] 6m Meteor Scatter longwire matching
Robert Bruninga bruninga at usna.eduThu Jan 10 19:54:57 UTC 2008
- Previous message: [aprssig] RE: 6m meteor Scatter project (radios&ants)
- Next message: [aprssig] RE: 6m MS network Performance Monitoring!
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Two pieces of 70 Ohm cable make a perfect 1/4 wave transformer from 50 ohms up to the 400 ohms of the long wire 6m Meter Scatter antenna. Just got it up today. See the details on the APRS Meteor Scatter web page: http://www.ew.usna.edu/~bruninga/meteors.html In another day or so, Ill have 1200 baud APRS Meteor Scatter going. Bob, WB4APR > -----Original Message----- > Subject: [aprssig] RE: 6m meteor Scatter project (radios&ants) > > > Or of course you could dig in a ground and > > terminate in a 150-300 ohm resistor at the > > far end.. > > My design uses a load resistor 1/4 wave > from the end far end which gives a virtual > ground. At 6 meters, that's just 4.5 extra > feet of wire and easier to implement... > > EZNEC showed that it works. It eliminates > the by-directional pattern but leaves > the main lobe in the forward direction > unchanged. The real advantage is that it > eliminates any standing waves making it > easy to design a matching network. > http://www.ew.usna.edu/~bruninga/meteors.html > > > (old military field radio trick in > > the 30-76 MHz PRC-25 and VRC-12 band. > > Works well, I (and many others) taught it > > in the Army, personally used it less than > > 2 years ago in a "distant land". Still works! > > and meant the difference between zero comm and > > 5X5. Simple idea, seldom used, ALWAYS works > > better than a whip, AND works better than a > > 5 element beam at 35 feet. Surprised me too > > when we did a controlled side by side test beam > > with a 1-1 VSWR and the vertical half-rhombic at >
- Previous message: [aprssig] RE: 6m meteor Scatter project (radios&ants)
- Next message: [aprssig] RE: 6m MS network Performance Monitoring!
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
More information about the aprssig mailing list
