Solid State Amp Info
Testing, Tuning, Repairs and modifications
These days there are a lot of solid state amplifiers to choose from.  Especially with the newer MOSFET units capable of very high power!
This will cover some simple specs, tuning and simple repairs and diagnostic procedures.
There are basically three types, the "Mobile" 12V transistor types, generally ranging from 50-300W.. the higher voltage transistor types ranging from 300-600W @ 28VDC and the MOSFET types ranging to well over 1KW but requiring 28-50VDC.

First the "mobile" style amps.  These are usually a single or dual transistor amp capable of 80-160W with some containing 4 devices capable of over 300W. 
BEWARE of the rated output power!  There are a couple manufacturers claiming over 350W when the transistors are only rated at 320W.  The 350W rating is at full saturation and they are NOT clean at these power levels. They usually require 10-30W input with more stages for lower power inputs.

The higher voltage units generally are not so portable and usually contain 28V transistors capable of 600W.  Very similar in design to the 12V amps.

The MOSFET amps are the newest thing for ALL bands and capable of well over 1KW but usually require 50VDC.  They are also very high gain requiring very little input to drive them to full power.  Usually well under 10W.  All the big manufacturers are moving to these and away from tube type units. 
All the mobile amps are of similar quality and design, but if you can find them, the Teletec brands were one of the best! Especially the higher freq units such as for 220 or 70cm.  Far superior transistors and linearity. 

As for the MOSFET units, there are a lot of kits and complete units out there.  W6PQL makes a wide variety of everything from kits to complete units for everything from HF to 2.4GHz.

Notes on "Broadband HF Amplifiers"
There were a LOT of these things built in the past for CB use and marketed as HF Amateur amplifiers.  It is very rare to find one of these that is FCC approved. The main reason is there is NO filtering and these thing had horrible harmonics all over the place! Avoid these for any type of amateur use!