[R-390] Kilocycle knob moves megacycle change knob

[Dan Merz]

Hi, my 390a has symptom that moving the kilocycle knob also moves the megacycle change knob. I haven't explored yet but it seems megacycle knob itself is "gummy" and not working right so I haven't forced it much. This receiver hasn't been used much in last 10 years but was working smoothly probably a year ago. And had been cleaned and lubed with synthetic oil, maybe 15 years ago. I suspect some shaft is sticking to cause this odd symptom.  Where to look first?

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