I have a chance to get a Palomar Elite 300 linear amp CHEAP! Is this
thing any good? I haven't been able to find any information on it and
it doesn't come with a manual. The questions I have a

Is this amp good for HF Freqs 10 meters down to 80 meters as the seller
claims?
What purpose does the preamp serve?
With a boost in transmitting power, how will this affect receiving?
Would I be transmitting further than I can actually receive?

Greetings! I don't believe that it will go down to 80 meters. The ones like
it that I have seen will generally go down to 40 meters. The pre amp is for
receive purposes only, and is generally the first thing to go on these type of
amps. They are made for the eleven meter crowd and that is where they do best.
I don't forsee any real change in your reception with the amp. It has a low
input of probably no more than 10 watts. What transiever are you planning on
using it with? I think its best use for you would be on ten meters with a QRP
setup. You may be able to get this one cheap, but you need to determine which
bands you would want it for and do some more homework on it first. Copper
electronics is the big seller of these things. You might be able to get some
more info there. If I were you I would save my money and get something
actually designed for amatuer radio use. Jon.