I think 1dB is a little optimistic for 75' of 9913 coax, it is in reality,
I
suspect, nearer 1.5dB.

Any loss ahead of your preamp adds directly to the noise figure of the
system so the best NF that you could ever have is 2.5dB plus a little form
the 221.
Also 20dB of gain in the preamp sounds like a sure way to produce
intermods in your radio.

Regards
Jeff

Well of course it is Jeff, but in moonbounce, noise figure is the holy
grail. There weren't as many folks on 432 and moonbounce in particular back
in 1979, but I NEVER was plagued with intermod off the moon, and the
directivity of the array kept me from having any from anywhere else.

W4ZCB