Oops. The LM-7 was also external DC powered. It was the first model that could be set for 12/14 and 24/28 VDC filament supply. Didn't catch that when I caught my other omission. Robert Downs - Houston <http://www.wa5cab.com> (Web Store) MVPA 9480 <wa5cab at cs.com> (Primary email) <wa5cab at comcast.net> (Backup email)