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I will try to get the diode disconnected, on one end at least, for a test. Just out of curiosity I placed my leads across the diode in circuit and read open leads. it looks like it might be a little tricky to de-solder and properly disconnect as the tuning coil that it is mounted on might be destroyed by either heat or by tugging on a lead too hard. I am tempted to just snip a lead and if the diode checks out OK then I can solder the lead back together. Again, since these diodes cause a multitude of problems I was hoping that somehow vertical sweep would be on the list, but I more or less figured that there was no way.
This set has always had me puzzled with the lack of vertical sweep and hum that have been it's symptoms since before the re-cap. I thought that the hum would go away after the power supply electrolytic capacitor replacement. No such luck! I am still searching, but I have yet to find any bad components. I am starting to think about ceramic discs. Most people leave them alone, but any component can be bad. There is one of the little brown jewels with 22 dot 17 marked in blue on it in the vertical sweep circuitry that has wax dripping off of it. Perhaps that is worth looking into. I sure wish that I had the college's LCR meter here at home! I have more than one digital VOM that has a capacitor test, but I have been told that this type of test is not reliable. Hmmm? I wouldn't think that the meter manufacturers would put this capability on most meters if they didn't work.
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