A regulated heater supply, with adjustable voltage, works very well. With current limiting at 10% above operating level, the inrush problem is also solved. One example, that has performed perfectly for 20 years, is shown at: www.zianet.com/k5am/amps/2mkw.html www.zianet.com/k5am/2mkw.pdf 73, Mark, K5AM www.zianet.com/k5am