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I have been working intermittently on my Whitby set. I have checked the alignment of the Front End, realigned the Video IF and Sound IF apart from the earlier replacement of capacitors, resistors etc. I still haven't gotten around to the chroma bandpass, chroma demodulator and matrix alignment.
I last weekend fixed (at least tempoarily) the red static convergence pot, replaced a few tubes and increased the horizontal drive marginally. With the drive increase and the efficiency coil adjustment, I have the horizontal output current at about 200mA.
You may recall I opted to not change the electrolytics. They were all healthy and the two Canadian Mallorys used in the 25 Hz power modification are not too bad. The leakage on the Mallorys remains at about 200uA.
I have been running the set a few hours at a time the last few weeks and the only problem has been vacuum failures. When I received the set, all the receiving tubes, including the picture tube, was original. I have now had 4 tubes fail and be replaced (3rd VIF, Video Output, 3.58 MHz oscillator and the Z demodulator. I have since replaced the X demodulator, 1st video amplifier, the Horiz. Damper, Focus Rectifier, HV Rectifier and Horiz Output Tube.
With the extra drive, the blooming effect has reduced and focus has improved. The picture is improving and with a little more work it should be quite acceptible.
I have attached some photos of it working this evening. Note the dolly which helps me rotate the heavy cabinet. I have made up a bunch of extender cable so that I can readily pull the chassis and hook it up to the CRT for further technical investigations.
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