George said: >I'm sure the BC610 that I used when I was a radio operator for Uncle >Sam was a single 250-TH modulated by a pair of 100-TH's. I'm sure George is correct on that. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com