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I checked the resistance on the osc and mixer and found that 3 pins (tied together) were off by a significant factor.
Unfortunately to get to the resistors I had to get under the osc trimming caps and coils. Luckily I did not have to pull everything apart this time but it was a job. A 6.8K resistor had drifted to 55K. Interesting the 10 ohm one was right on. With my big paws it was a chore but I got it replaced.
Interestingly, I found a wire in that compartment that was pinned between a bracket and the top of the chassis. See attached picture. It must have been that way since assembly I was going to loosen the bracket and move the wire, but the screw heads are hidden under a sub chassis. So I would have had to pull the whole osc section apart.
Considered replacing the wire but have been burnt enough times by just making one more little improvement and given that tiny working space I decided that it is not subject to streess or movement and has been that way for 75 years, so I would leave well enough alone. Surprised this got through QC.
Net effect, some improvement on the two higher bands, but not great. Not really an issue as I don't roam up there much. However 40 meters sounded much better so you sure nailed an issue.
I'm done, I've got about 5 weeks into this project and its working very well for my purposes. I'm going to pair it with the HT-9 on 160.