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U1 kit - low Freq

"Chris D" #1261 Finally got around to fixing my dead U1 kit. Seems to be working fine except for low freq. Did the C4,5 cap change to 18pF from 22pF. Didn't seem to move it much. Highest I can get it is 10139.5 Will try 15pF. Anyone else have much trouble pushing it up to where it should be? 72, Chris KQ2RP
"andyfoad@..." #1263 IIRC you remove C5. Me and Tony G0BZB did that and now we can tune both the QRSS and WSPR segments. 73 de Andy toggle quoted message Show quoted text --- In QRPLabs@..., "Chris D" <kq2rp.cw@...> wrote: Finally got around to fixing my dead U1 kit. Seems to be working fine except for low freq. Did the C4,5 cap change to 18pF from 22pF. Didn't seem to move it much. Highest I can get it is 10139.5 Will try 15pF. Anyone else have much trouble pushing it up to where it should be? 72, Chris KQ2RP
Tony Volpe #1265 I had that trouble and in the end I just left out the capacitor that was in parallel with the trimmer. This allowed me to move a lot higher, even though the tuning was made a bit more sensitive. I can't remember what the cap number was, but it is the one that is in parallel with the trimmer. You'll find it on the circuit diagram.? Once set it will stay put, so the bit of fiddle in getting it exactly on is worth the trouble. I set mine about ten months ago and it has been on more or less 24/7 ever since. Regards G0BZB Tony
"Chris D" #1269 Will try the C5 removal. Thanks gents. Did you leave C4 as 22 pf or 18? 72, Chris KQ2RP
"Chris D" #1270 Hmmmm.... Revisiting the board layout, apparently someone in this group (who shall remain nameless, with aging eyes) does not know the difference between a 3 and a 5. Wonder what happens when you change C3 to 18pF.... apparently not much.... :-/ Chris toggle quoted message Show quoted text --- In QRPLabs@..., "Chris D" <kq2rp.cw@...> wrote: Will try the C5 removal. Thanks gents. Did you leave C4 as 22 pf or 18? 72, Chris KQ2RP

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