I had similar problems with my ft980 and replacing the trimmer capacitor you mention and worked for me its located on the VCO/PLL board part number TC4001 its a? 1-3pf its inside a metal enclosure you will have to carefully remove the lid by unsoldering the tags ether side,? a replacement trimmer is not easy to find, but I do have one here if you have trouble? getting hold of one just e-mail me my info is good on QRZ.co