Quote:
Originally Posted by old_coot88
What's happening to R89, the 470K resistor? Is it getting hot, or remaining cold? If R89 remains cold, there may be a leakage path from the 1X2 socket itself to ground that's dragging down the HV. If R89 is getting hot, it may be that the 1X2 (in this case either one) is gassy and passing unrectified pulse that's hammering the resistor.
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Stupid question, but I'm not afraid to look stupid to get it right. "Hot" and "cold" aren't euphemisms right? If they are not euphemisms then would a simple finger test be recommended for a thermometer (after discharging the HV of course)? How "hot" is hot and how "cold" can it run? Also how long should the set heat up before testing temp?
Quote:
Originally Posted by old_coot88
This is with the doorknob removed, right?
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My results of:
Over 95V I get sparking on the inside of the old 1X2, and sparking plus blue glow on the new 1X2 were with the doorknob installed.
Previously when I thought I had removed the doorknob from the equation I had infact not. Tonight I removed, completely, the doorknob from the set. The results with the doorknob removed:
Blue glow on the new 1X2 (although not as strong as when the capacitor is installed). No glow on the old 1X2. After leaving the voltage around 100V for 70 seconds or so both tubes made a pffffssst noise. I fired the set down immediately after hearing this.
The only things that are connected post 1X2 at this point are the filament loop, two resistors, and the anode connection on the picture tube. I've tested the set without the anode connection to the picture tube and it failed. Both resistors measure within 20%. The filament loop is solid and double insulated where is loops through the flyback. While the doorknob was removed I took the time to make sure all solder points on the base of the 1X2 are smooth. I'm thinking that the only two things that remain are the 1X2 itself, and the flyback output to the 1X2. I'm going to try another 1X2. As far as the flyback output is concerned, I will obtain a high voltage probe to measure the output. Does any one know what the voltage should read out of the flyback? Hopefully this will pinpoint the exact problem.