..you get it
Dicks, pussies and assholes
Transponders of this type don't demodulate the uplink signal. They just convert to a different frequency and amplify the downlink signal. You could do the same thing with a C-band satellite, but the hardware to operate in 4-6GHz at >100W is expensive and you need a big reflector. At UHF, you can do it at lower power with cheap parts.
1. You will have some great shadow-free images of the tops those clouds.
2. Uh, its dark.
However, radar can see through clouds and in darkness.
Memory fault -- core...uh...um...core... Oh dammit, I forget!