110 likes | 149 Vues
W6RVB 2 METER ROOF ANT =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=. THE SIMPLE FORMULA FOR A 2 METER ANTENNA IS 468/FREQ FOR A CENTER FREQUENCY OF 146 MHZ THIS YIELDS ~ 19.5” In a ground plane configuration such an antenna looks like:. W6RVB 2 METER ROOF ANT =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=.
E N D
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= THE SIMPLE FORMULA FOR A 2 METER ANTENNA IS 468/FREQ FOR A CENTER FREQUENCY OF 146 MHZ THIS YIELDS ~ 19.5” In a ground plane configuration such an antenna looks like:
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= We utilize a SO 239 socket & Right angle Connector And a thin piece of aluminum 6” x 18”: Aluminum sheet
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= And a thin brass rod, 1/16 “ in diameter. Obtained at Amazon –or- E bay (K & S Metals)
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= • Galvanized steel also works well and is quite inexpensive.
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= THE SIMPLE FORMULA FOR A 2 METER ANTENNA IS 468/FREQ FOR A CENTER FREQUENCY OF 146 MHZ THIS YIELDS ~ 19.5” While a ground plane does not offer gain, it is simple, effective, And yields an SWR of nearly 1:1 Replacing the 2- 4 wire radials with a flat piece of metal We can have an effect nearly as effective as a ground plane:
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Temporary Position of roof edge and over gutter
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= View from the ground
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= View from the ground
W6RVB 2 METER ROOF ANT=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= With a little luck and trimming you can attain: a 1:1 SWR, 50 Ohms & No reactance