>The older, (at least 20 years), CBs had 5W of broadcast power.  You
>might pick-up one of these older units at a garage sale and have 25%
>more power.

Not exactly.  The older radios had 5 watts of DC power going INTO the final amplifier.  The new requirement is for  4 watts of power OUT of the radio.  The only way an old radio could have more power than a new one (assuming it hasn't been modified to exceed its rated power) is if the final amplifer is more then 80% efficent.  That's not too likely, especially since the 5W radio is 20 years old.

Bill