> The legacy switches like the B&W shorted the unused ports
> to ground as a "lightning protection" feature. There was
> some switch advertised as "Protax" that had this.
> I believe for a wafer switch like this, it basically costs nothing
> to do it. With relays, it does cost something.
This is a B&W 550A. Unused ports are not grounded.
> Does this mean if you have one beam aimed at the Caribbean and one on Europe
> > and only the EU antenna is selected, you're still receiving stations on the
> Caribbean beam but 45dB weaker? Is this an issue?
Yes, this is what it means. If your European antenna has more than ~45dB of
directivity, then it could be an issue.
For more fun and debate, I made measurements on one of my RCS-4. Port 4 was the
reference port - connected to a 50 ohm load. The isolation between port 3 and
port 4 was the worst, about 43 dB at 30 MHz and 49 dB at 14 MHz. Port 1 to port
4 was about 5 dB better. Since I'm using one my RCS-4's to switch between
beverages, I also checked at 1.8 MHz. 65 dB between ports 4 and 3. That's
probably adequate unless one of the ports is connected to a much higher gain
antenna, like the 160 transmit antenna.
73,
Steve, N2IC
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