having never used a dehydrator (or oven) before to dehydrate my own food, how do you know how much water to add to rehydrate a meal? I'm assuming one would weigh the food before and after dehydrating and calculate the water weight that was lost. Right? Am I on the right track or way out in left feild here?

Typically it's a one to one ratio...one cup dehydrated food + one cup of boiling water.

It depends on the food in question. Vegetables, grains, fruits, pasta, etc take 1:1 on average. Soups, sauces will take more.

If in question you can do either a pre weigh or a pre measure then check after drying it.

I often do measuring as I find it easier.

Just remember - you can add more water as needed, a bit harder if you start with too much water ;-)

cool. Thanks for the advice!

Justin - here is an article I wrote for the Washington Trails Association that is a small primer on drying your foods and rehydrating them.

How to do It — Dehydrating Food

This should give you a good start and if you have any questions at all please feel free to ask me. There is also a selection of simple recipes with the article. Enjoy!

The other thing to consider is the power requirement for a dehydrator.

If you need to dry a lot of food and hurry it up, then you will seek the higher-powered machines, typically well in excess of 1000 watts. However, you don't get something for nothing, and your electricity bill will be high for a lot of use. The 500-watt machines are obviously more economical, but much slower.

I have free AC power from a photovoltaic system, but only if I keep the dehydrator in the 500-watt range. If the dehydrator is over 1000 watts, the voltage is insufficient or else fuses blow.
--B.G.--