开云体育

FT-101ZD intermittent reduced output on 80m only

KQ4NUO All Messages By This Member #598 SYMPTOMS: - Full output power (sometimes) on 80m only. - Reduced output power only at ca. 50% intermittently (sometimes) and on 80m only. - All other bands operate normally. ? * When this does occurs, have to adjust the "Plate" to extreme left *(out of 80m marking range, different position then when operating normally)* to tune that 50% reduced power. Otherwise the transceiver seems to operate normally. ? Invite ideas on what to look for.
Jacques Fortin VE2JFE All Messages By This Member #599 开云体育 Hi Alex, Call it an educated guess if you like, but I believe that C9 in the output tank section, is defective (ceramic, 100pF, 3kV rating cap). ? 73, Jacques, VE2JFE in Montreal ? SYMPTOMS: - Full output power (sometimes) on 80m only. - Reduced output power only at ca. 50% intermittently (sometimes) and on 80m only. - All other bands operate normally. ? * When this does occurs, have to adjust the "Plate" to extreme left (out of 80m marking range, different position then when operating normally) to tune that 50% reduced power. Otherwise the transceiver seems to operate normally. ? Invite ideas on what to look for. ?
KQ4NUO All Messages By This Member #600 Jacques, your guess was correct, pretty clever thinking. Thank you for replying to message with your help. ? C9: It was labeled NTK 112K, only have a multimeter and it measured open (no charging). Replaced with a 100pf/3kv ceramic. C4: Since already in area, replaced C4 also. It was labeled NTK 302k. It seemed to charge up with meter but very quickly. Tried to replace with a 470pf (close to drawing) but didn't work good. So replaced with 330pf/3kv ceramic,, it works. It is way tight area under the PA box where switch is, very difficult to work in.? Fortunately the new caps are much smaller than the old ones, giving some extra space. I have acquired a complete Elko-cap replacement kit for the radio and will later start replacing all the elko's. There are what looks like qty>50 elecrolytic caps in the kit, will be a big job. Probably work one section at a time. ? The radio is actually an ZSD model for 10W output. from Japanese market? It's same radio otherwise as the ZD Now have the PA board for twin tubes and am considering altering for 100W. Radio is in excellent condition. ? Thanks again!! :-))

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