I have been trying to set up my radios to run on solar
and run that way with no battery if I need to,
one of the things I noticed is that the charge controllers need a battery to work,
if you have no battery it is going to break your radio or they are not going to work at all.
so I started looking at just making a voltage regulator to cut back the 22V open circuit that the 12V solar panels have out.
but that will be getting rid of quite a bit of heat unless the panel voltage drops, so I started looking for DC to DC converters to solve that issue, and there were a few, but they were not very efficient and they were very pricey
then I found ebay...
http://www.ebay.com/itm/LM2596-DC-DC-Step-Down-CC-CV-Adjustable-Power-Supply-Module-Output-DC-1-5V-35V-/250954117473?pt=LH_DefaultDomain_0&hash=item3a6e07f161for $2.16 (and that is shipped)
I can get an efficient regulator that will let me power the HT radios (or my FT-817) direct off of a 30W panel
(or maybe smaller depending on my power out requirements) and I will need no battery if my battery fails at some point in the future.
now I know that on HF it is likely to make to much radio noise,
but should work perfect for UHF/VHF
and I can set the charge voltage if I am charging a battery with them
and I can set it to charge lithium batteries as well,
so I plan on ordering 10 or so of them.
and here are the 30W panels I ordered
http://www.amazon.com/LiteFuze%C2%AE-Mono-crystalline-Solar-Panel-Watt/dp/B0079OD3I6/ref=pd_rhf_dp_p_t_2and I already have a pile of 12W panels to play with
http://www.goldmine-elec-products.com/prodinfo.asp?number=G1821612W is enough to run my HT radios, but not at less than .9A that it can give,
so that DC to DC converter will be a huge help