What still have is the original Comet tri-band antenna (6m, 2m & 440MHz) with a repeater Tx frequency of 440.025. The Comet antenna is not what I deem usable at that frequency . I simply found one that was... s.
> n...@... wrote: > Not sure what you consider "usable", but I haven't had > any bandwidth problems with Comet antennas. I just checked > my GP9 antenna at home & the return loss is <=20 dB (1% > reflected power) from 444 to 450 MHz. It does go up a bit > from there: 3% @ 443 MHz, 4% @ 442 MHz, & 5% @ 441 & 440 > MHz. 2 meters is similarly good: <1% from 146 to 148, 2.5% > @ 145 MHz, 4% @ 144.5 MHz. BTW, it's being fed with 30' > of 1/2" Heliax so negligible loss between the Bird & antenna. > > I once bought a "Comet knockoff" at the swap meet a few years > ago that was obviously a 430-440 cut antenna even though it > was labeled 440-450, as it had very high reflected power at > the top end of the band. Perhaps that is what you had. > Bob NO6B > > At 6/2/2009 05:22, you wrote: > > >All that glitters is not gold... > > > >If you sweep the typical Comet, Hustler and Diamond Multi-band > >antennas... you'll find they are fairly limited in band width > >and rarely cover an entire Amateur Band Segment with decent > >SWR (reflected power, return loss) values. They work fairly > >well for many people in casual FM service but you might find > >your repeater operates at one portion of the band where the > >SWR value is not pretty... > > > >As an example, the SWR of a Comet & Hustler Multi-band Antenna > >I have here is not a decent, what I deem a usable value at the > >low end of the 440 to 450 Amateur Band... Even with a decent > >circulator / isolator panel in for protection I would be > >wary. >
