Most Gell Cell battery experts would probably tell you 13.6 V is about optimum for float charging a Lead Acid gell cell.  Going to 14V or higher tends to shorten their lifespan by warming them excessively so that they "dry out" more quickly.

  Personally, I have for decades used a small 13.6V regulated power supply to float charge my shack gell cells.  These have run my ham shack for decades and the gell cells tend to easily last past their projected life span this way.

   Ed

  As others here have already said, it is not a good idea to top off NiCd batteries, but NiMH are different and the topping off does not shorten their charge hold over time as occurs to NiCd's.

   As far as running your batteries in mid QSO,  I always order the AA battery case option for my HTs when I buy them, and keep it with me.  This allows me to always have power available for the HT, even when the AC mains are not available, by simly purchasing and carrying a supply of AA cels.

   Ed   K7AAT

 The 746Pro is the successor to the now unavailable 746.  It has many enhancements over the earlier radio and in many ways is more similar to the 756Pro than the 746.


  Ed

  Without being judgemental, the answer to your question is NO.  There are no mods for what you ask, due to the design of the FT-817.  There is a Yaesu sanctioned MARS/CAP mod which will extend operations a short bit outside the prescribed amateur bands, but the FT-817 is not capable of going into the 150MHz range, or the 460MHz range.


  Ed

Don't know if this will help, but a manual for the Yaesu FTdx560 can be found here:

http://www.mods.dk/view.php?ListManuals=yaesu

  Not sure what you mean by using the term "pure".  However, "Copperclad" is copper plated steel wire.  It is quite strong and should hold up to about anything you require in your area, as long as you use proper antenna mounting design and good weather-tight connections.


   Ed