You didn't give a model number nor a link for the Panorama, but the one I've seen has a single connector, and selects Vertical/Horizontal based on being fed 13 or 18 volts.
SO, it's good for running only one receiver at a time.
The
B1 stacked Eagle Aspen LNBF is the only such C-band LNBF available in North America, that I've seen.
I'm not a big proponent of this, but you could use high frequency satellite-grade splitters to run multiple receivers.
A proper powered switch would be preferable, but the availability of such a switch is pretty slim.
To mention the only one I know of, would be to generate more confusion than solution.
A better and more traditional way, would be to use an
LNBF with two outputs.
Those are fed to the two inputs of a 2x4 or 2x8 multiswitch.
OR, to two of the four inputs of a 4x4 or 4x8 multiswitch.
Then, each multiswitch output could be fed to a different receiver, which would be free to select Vertical or Horizontal.
If you chose a
4x4 or
4x8 switch, the two unused inputs could go to two outputs of a Ku band LNBF,
such as this one.
Then, by simply selecting between 22khz off (for C-band) or 22khz on (for Ku), you could select different dishes and bands.
edit: I believe the 421 is just like the Panorama - it has a single output, so won't work here.
ALSO: you've got comments in multiple threads throughout the FTA Department, and I don't know exactly how you are wiring up your Zinwell.
I assume it's a 6x8, but for this application, it is only effective as a 4x8 multiswitch - the other two inputs are of NO USE.
What other LNBs are you trying to use with it?