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Title: speech amp mods for globe champion Post by: K1REX on July 27, 2005, 01:40:25 PM . . . wonder if any body out there has worked out basic speech amp mods for Globe Champion to open up the audio passband on this transmitter?
Thanks (in advance) for your response! Stephen Merriman, K1REX serenity@world.std.com Title: speech amp mods for globe champion Post by: Steve W8TOW on July 27, 2005, 02:18:37 PM I did a Champ 300/350 a few years ago for a friend.. AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
Briefly, here is what I did: Pulled the finals & replaced with a pair of 4x150B's, Solid stated the HV supply bypassing the rect fil windings, replaced the pair of PS chokes with 1 bigger iron... temp compsensated the VFO Replaced all the couplets in the AF section with descrete components, changed it over to PP driver and used a 12AU7 with Hammond driver iron, replaced the 809's with 811A's, I have all the documentation if you want... 73 steve w8tow PS, due to the PS and tank limitations, you still only get about 200 watts carrier...or so...any more & the iron starts to complain! |