[Kenwood] Emergency Batteries

[Jim Miller]

I agree that when the batteries are charged, which is where you want them or
all of for naught, that your voltage is too high to use without stressing
your equipment, BUT, I can see what you are trying to do which is to have
more reserve voltage available.  This CAN be done if you will simply install
a regulator on the output of the series batteries.  True, you will loose .7
volts doing this but you could also install a manual knife switch or jumper
wire to bypass the regulator when the voltage dropped below the unsafe
level.  You could do the same thing by using two simple dropping diodes in
series (.7v each to drop 1.4 volts) and then also switched or jumpered out,
again when the voltage came within safe levels on discharge.  NOW, while the
regulator or diodes are in line, you ARE losing the power consumed in the .7
voltage drop in each diode, but you still have the additional reserve
voltage and time that it gives you before you actually switch it out.  NOW,
somebody mentioned the charging system has to be for the increased voltage
and I would recommend a float charger being built for each of the batteries
and also install voltage monitors (I would use three) for each battery (2)
and another for total voltage (for reading at-a-glance).  It can be done, it
will work, not a big deal, you will benefit but it may not get quite as much
as you think.  If you already have those batteries, go for it, if not, buy
two (or more) batteries the same (and just use 12v batteries).

Just my opinion,
73, de Jim KG0KP