Yes, I bought a TS-940 and have been trying to diagnose hilarity.
The calibration marker circuit is .. sub-optimal, and picks up a lot of stray, random noise throughout the radio.
There’s a very nice write-up about this, applicable to at least the TS-930 and TS-940:
The TS-940 power supply is not the best designed and it’ll go pop, taking your hard-to-find driver transistors with it. (k6iok)[https://k6iok.com/] has replacement power supply bits to drop in and it works!
K6IOK installed his replacement PSU in my TS-940 and it runs like a charm! The radio runs much cooler and it’s much lighter. However, I’ve been having some RF issues which I bet are due to this rig.