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staticmind · 21st Apr 2020, 8:03 pm

Need an advice here. There's a problem, notably with the tuner and the PCC88. There's no "static/snow" as there should be, when there's no input. Gently bumping the PCC88 with a screwdriver handle seems to make static appear briefly and randomly. I tried it once again, but this time the picture disappeared, and the line oscillator stopped, since the 15 kHz tone was not audible any longer.

I turned off the TV after two seconds of observing this, and the screen showed some life, when powering off - it shows the raster collapsing as it should, but this time it collapsed into a single bright dot which remained in the screen for the next 10 seconds. That can't be good!

I have ordered a replacement PCC88. My theory is that it might have an internal short, pulling down the +180V (b) supply down through the 1M resistor. The b-supply is also used for the line oscillator circuits, and that could explain why the 15 kHz would disappear, right?

What can I do to not have the stationary "dot" shining at the screen for too long? Just discharge the EHT with my EHT probe? Or does this not matter at all as the AW43-88 is aluminized?

21st Apr 2020, 8:03 pm	#41
staticmind Tetrode Join Date: Sep 2019 Location: Aalborg, Denmark Posts: 97	Re: B&O Capri 606 TV (17") restoration Need an advice here. There's a problem, notably with the tuner and the PCC88. There's no "static/snow" as there should be, when there's no input. Gently bumping the PCC88 with a screwdriver handle seems to make static appear briefly and randomly. I tried it once again, but this time the picture disappeared, and the line oscillator stopped, since the 15 kHz tone was not audible any longer. I turned off the TV after two seconds of observing this, and the screen showed some life, when powering off - it shows the raster collapsing as it should, but this time it collapsed into a single bright dot which remained in the screen for the next 10 seconds. That can't be good! I have ordered a replacement PCC88. My theory is that it might have an internal short, pulling down the +180V (b) supply down through the 1M resistor. The b-supply is also used for the line oscillator circuits, and that could explain why the 15 kHz would disappear, right? What can I do to not have the stationary "dot" shining at the screen for too long? Just discharge the EHT with my EHT probe? Or does this not matter at all as the AW43-88 is aluminized?