Joe,
The latest RFS/Celwave catalog identifies the 200-series antenna as the
"Stationmaster II."
While a PD-200 ordered with a center frequency of 145.06 MHz will
probably do very well for a 2m repeater operating at 145.360 TX and
144.760 RX, it will NOT do well for a repeater operating at 147.300 TX
and 147.900 RX. That was the point I wanted to make; the PD-200 has a
very narrow bandwidth that does not cover the entire 2m band, and it
must be ordered for the specific repeater pair desired. For this
reason, a PD200 antenna ordered for service on one 2m repeater pair may
be useless for service on a different 2m repeater pair.
On the other hand, the PD220-2 "Super Stationmaster" covers the entire
2m band and can be used on any repeater pair within that band with no
concern about specific frequencies. You are absolutely correct in your
observation that the gain of the PD220-2 (and similar antennas from
other manufacturers) is derated to 4.8 dBd due to length constraints.
However, in practical terms, this gain reduction is irrelevant.
73, Eric Lemmon WB6FLY
mch wrote:
>
> Eric Lemmon wrote:
> >
> > The PD-200, also known as the "Stationmaster II" is a very narrow-band
> > antenna designed especially for simplex use or for repeater systems
> > having separate RX and TX antennas. It is not a good choice for duplex
> > service, even on 2m. The PD-200 has only a 1.5 MHz bandwidth, and it
> > must be custom-ordered for the exact frequency.
>
> The PD200 is the original Stationmaster. I'm not sure where you are
> getting the II from (not to be confused with the PD220 Super
> Stationmaster or PD220-2 142-150 MHz variant).
>
> It's fine on 2M repeaters. You said it: bandwidth is 1.5 MHz. That's
> more than enough for 99.999% of the 2M repeaters out there. If you are
> ordering one, get it cut for your TX frequency and the RX (if using a
> 600 kHz split) will still be in spec.
>
> One big difference between the two is that the PD200 is spec'ed at 5.5
> dB across the entire range while the PD220 is DERATED to 4.8dB gain
> below 150 MHz (from 5.25dB above 150 MHz), so with the PD200 you get a
> little more gain and a little more out of band rejection.
>
> Joe M.
>
>
> Yahoo! Groups Links
>
>
>
>
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