On 80 meters only, I have moderate distortion of transmitted SSB ouput from
my KPA100. It's not RF in shack or antenna related as I confirmed on-air reports by listening on another receiver while transmitting into a dummy load. The distortion is present only with the KPA100 on: At 10 Watts (KPA100 off), no distortion; At 11 Watts (KPA100 on), distortion, which gets no worse as I run up to 100 Watts. The distortion is actually a loud "crack" at the start of a new word or syllable. However, a continuous sound is clean. A tuning fork by the mike modulating at full power sounds fine. From this I suspect the TR switch in the KPA100. Tapping components doesn't reveal anything loose. In the archives I found reports and fixes for this exact problem. However, my KPA100 (Rev E of January 18, 2007) already has the new components from the fixes: 1K added in parallel to RFC3, C31 changed to .22mF. I also tried changing R4 to 39K, per Don's suggestion of 3/27/00, but no joy. Any ideas? -- Dick & Judy Lamb 44 Post RD Iowa City IA 52245-3622 Landline 319.338.2721 Dick's cell 319.471.3834 Judy's cell 319.471.3822 email [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Please ignore this email & respond to email of same title yesterday. I apologize for duplication, but I thought my earlier email was lost. K0KK
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