Originally Posted By: Folsom
Instead of all these electromechannical switches, have you looked at some solid state SP2T or higher switches.


Yeah, the thought has occurred to me, but apparently I'm not very good with my EMI/EMC stuff! smile

And this thing would definitely need to be very good to avoid degrading the excellent picture quality we enjoy here!

The one you linked to has only 24dB isolation, whereas the sealed mechanical switches I'm using here have 60dB+. There are probably better semiconductors to use, though, but I'm not yet advanced enough to lay them out and isolate things well enough.

However.. one of my next projects is to try building a low noise RF preamp for masthead applications. There are $2 /$4.50 chips from Digikey that quote < 0.5dB noise figures for this purpose, and with a bit of luck I might keep the total figure under 1.0dB.

Off-the-shelf pre-amps generally score noise of 3-4dB or higher, so this could be quite useful if I can pull it off. A commercial product with that kind of figure costs >$200 or so (I know, I have one of them here..).

Cheers