Hi Gerry,
>The thing to watch for with power supplies is loaded and unloaded
>voltage, also does the power supply have a high enough amperage
>rating.
>
>Eg a typical phone power supply will be 100ma 9V. Guess what you
>get when you attach a multimeter.....13-18VOLTS!!! The above rating
>is a loaded rating.
This is true with the kind of crude "wall wart" supplies that are shipped with most gear, including the PA-3/3B that Yamaha uses. It is not true, however, of computer-grade switching supplies that laptops use, which are designed to handle a wide variety of loads. I use such a supply with my AN1x, and it is 12V no-load, 12V full load. I like them because they are smaller and lighter than wall warts. A parts house like Digi-Key or Mouser probably has a laptop-style supply in about the same voltage and current rating as the Yamaha supply, but is smaller and lighter. If in doubt, choose a slightly higher current rating than the original supply, but try to stay with the same voltage rating.
I used to sell a suitable product on my website, but I can't get a supply of the particular unit I was selling anymore, and the replacement is a bit more money. (I used to sell them for $15 each; the replacement would be more like $25-30, which I thought was too expensive to bother with.) I still have 2 or 3 of the original ones laying around in my lab, if anyone is interested. Contact me offline.
Regards,
-BW
--
Bruce Wahler
Ashby Solutions™
http://music.ashbysolutions.com978.386.7389 voice/fax
bruce@...