there have't been many posts in this section lately, so in the interest of stimulating conversation, I invite you to visit the following web page.
http://williamkapp.fortunecity.com/id41.htm
While the Eco Magneto Clock co was the industry leader, Other companies put out some interesting products. I only have a small version of this companies watchman devices, but they made some gorgeous devices with independent regulators.
Happy hunting,
Bill Kapp