I just finisher building a vaporizer prototype, si,ilar to the JB200. The 12v heat source that I used was a 1990 VW deisel glow plug. It easily reaches vaporization temp, and is small enough to fit into the front entrance. I wired it, with an old extension cord, that I cut in half, and used the plug portions for the battery disconect, and hard wired the other side to the battery terminals and glow plug. Using a teaspoon of wood bleach, I inserted it into the hive. It took about a minute to start, and a total of 4 minutes to complete. There are a few minor things to take care of, mostly for ease of use, but the grand total was 20 bucks!
Also by using an extension cord, I can virtually eliminate carrying a battery around. You simply plug it in the middle of the vaporizer and battery. I figure I can get a used battery at the junk yard, but then decided to go that route instead. The glow plug was about 12 bucks at the Auto Zone.
Thye acid tray is rectangular, and a potion of it actually wraps aroung the tip of the plug. Maybe I'll try to post a picture if anybody is interested.