585/Repairs: Difference between revisions

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:'''Symptom:''' No trace, HV low despite maximum setting
:'''Symptom:''' No trace, HV low despite maximum setting
:'''Root cause:''' HV [[Bumble Bee capacitors|PIO "Bumble Bee" capacitors]] leaky (~180 μA at 2 kV); no trace because CRT grid too negative wrt. cathode
:'''Root cause:''' HV [[Bumble Bee capacitors|PIO "Bumble Bee" capacitors]] leaky (~180 μA at 2 kV); no trace because CRT grid too negative wrt. cathode
:'''Solution:''' Replace caps
:'''Solution:''' Replace caps with modern ceramic equivalents
:<gallery>
:<gallery>
585 HV caps old.jpg | old PIO caps in place
585 HV caps old.jpg | old PIO caps in place
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:'''Symptom:''' Trace fading after ~10 minutes operation
:'''Symptom:''' Trace fading after ~10 minutes operation
:'''Root cause:''' HV resonant cap (C808) leaky, overheating (visible bulge)
:'''Root cause:''' HV resonant cap (C808) leaky, overheating (visible bulge)
:'''Solution:''' Replace cap
:'''Solution:''' Replace cap with modern ceramic equivalent
:<gallery>
:<gallery>
585-c808-therm.jpg | Thermal image
585-c808-therm.jpg | Thermal image
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:<gallery>
:<gallery>
585-neon-1.jpg | broken lead
585-neon-1.jpg | broken lead
585-neon-2.jpg | repaired leads (before encapsulation with epoxy)
585-neon-2.jpg | repaired leads (before cleaning and epoxy encapsulation)
</gallery>
</gallery>
:--[[User:Peter|Peter]] ([[User talk:Peter|talk]]) 02:45, 4 May 2019 (PDT)
:--[[User:Peter|Peter]] ([[User talk:Peter|talk]]) 02:45, 4 May 2019 (PDT)