It seems incredible, but there is a lithium battery in the Kenwood TS570 that apparently lasts about 6 months. Replacing it is a major trip into the innards of your radio.

Clif of AVVID (a Kenwood Service center) was kind enough to tell me what to do, and I thought I would write up his instructions and my experience in case someone else needs it.

According to Clif, the microprocessor must reset correctly or the battery will drain quickly. Therefore you must follow these instructions, as odd as they seem.

Before you begin, you need the radio on a nonconductive surface, a Phillips screwdriver and a CR2032 battery (Radio Shack has them). You also need the radio's power supply hooked up.

1. Have the radio hooked up to 12V. Turn the radio off but leave the supply on.
2. Remove the four screws from the top of the case.
3. Then remove the 4 screws on the side and lift the top free.
4. Turn the radio over and remove the 4 screws from the bottom that holds the entire case on. Don't bother with the service panel.
5. Turn the radio right side up and notice there are 4 screws (2 on each side) that hold the front panel on. Two of these are in slots, and two are in holes. Remove all 4 screws. BE CAREFUL. The panel is attached with several cables and yanking them loose is probably not a good idea.
6. Carefully separate the panel from the radio chassis. Note the battery in the little holder. The + side of the battery is facing out.
7. The battery holder is spring-loaded; you don't need to open it. Just gently push the battery and slide it upwards, freeing it of the holder and replace it with the new battery (remember + faces you).
8. Reseat the panel, lining up the screw holes and replace the screws.
9. If you want, at this point, turn the radio on and off again.
10. Replace the covers. Remember, don't put the side screws in until the top and bottom are in place.

That's it! According to Clif the problem won't reoccur. We'll see! Just be careful when you attempt this. Lots of things can go wrong. The case is very tight fitting, so don't drop the pieces and bend them out of shape or you will be sorry. Good luck!

UPDATE

As of March 29th, my battery failed again (yep, about 6 months). I have a month left on my warrantee, so I'm planning on trying to get something resolved. I'll post here about what I find out.

Kenwood did in fact take the Radio back and apparently installed a diode at no charge. With any luck, this will fix the problem. (As of August 1999, so far so good!)