Bottlehead Kits > Eros Tape

How long is too long for resistors to bleed off the voltage?

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PS2500:
When I run the preliminary voltage tests on the transformer and power supply stage of the Eros it takes far longer for the capacitor to lose its charge after the 375V measurement. According to the manual "The filter capacitors store charge and the 270K bleeder resistors take several seconds to 'bleed off' that voltage".

In my case it takes a few minutes. For example, having just tested a third time, with the power on for around 30 seconds, it took 35 seconds after power off to drop to 200V, and then around 1'30" to get to 99V. And still reading 28V after 3 minutes.

Something wrong there. What do I need to check?

Paul Birkeland:
I would be checking the solder joints on the 270K resistors.

PS2500:
I couldn't see any problem with them (checked before posting the question; however I'm no expert at visually judging a good joint). Perhaps I just need to unsolder the wires from the power supply so that I can remove it, and then redo those two resistors.

Adrian:
Perhaps just "re-flowing" the solder joints will help instead of completely removing them.
Reheat them and then add just a tiny bit more solder (or just reheating the existing solder only).

PS2500:
I did think about reflowing, but access is awkward and it's pretty tight in there to get both ends of the resistors - I want to avoid nicking other wires (insulation) with the soldering iron. I think it's actually easier in the long run, albeit slower, to just desolder them with the power supply removed and reinstall them. There's only a couple of wires that have to be disconnected to get the power supply off.

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