I've had a Kenwood digital VFO, the DFC-230 for years. Recently
I noticed (and never have before) that the PLL would momentarily
lose lock when the frequency readout transitioned from 19.9 to
20.1; e.g. 7020, 7040, 7060 etc. as the frequency control knob
was very s l o w l y turned.

Anyone other owners of the DFC-230 seen this?

73
Don K6LTS
email address in QRZ.com

I have not seen this exact problem.

I have two DFC-230's which have exhibited various weird problems. In
both cases, the solution was to add star washers between the circuit
board and the mounting tabs. Over time, the "grounds" provided by the
contact between the solder and the mounting tabs oxidizes and becomes
high resistance. The star washers make a gas tight connection.
Once this was done, the problems went away and both units have
performed flawlessly.

Tim AA6DQ