![]() ![]() ![]() So the two 6-10pF SMD trimmers are at fault. When tapping on the trimmer capacitors for VCO1 and VCO2 I could reproduce the problem. I opened the tin can where the VCO is located and tapped with a trim key on several components. That was the case so the culprit has to be in the VCO. 216 MHz and tuned an Icom R10 receiver on the VCO frequency to establish if I could here it there too. So I figured out that the VCO mixes on approx. I checked the voltages from the 3 regulators on the PLL board bud couldn't find anything wrong there. It took me about 3 nights to identify the problem and first of all I suspected a bad soldering joint or something like that.Ĭhecking the PLL circuit diagram I noticed that the modulation circuit uses also part of the receiving circuit so I concentrated on that. After heating up (approximately 20 minutes) the transceiver produces a crackling noise and a lot of his heard from the internal speaker when on 2 meters FM/AM/SSB/CW. Icom IC-706MKIIG PLL Problem Stan Joosen (PA8C) on February 6, 2014 ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |