Author Topic: Newbie help pls measuring voltage on C836 on phillips pm3233 piwer supply  (Read 191 times)

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Offline jimnoonan@sky.com

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I feel very foolish asking this but I am confused. My pm3233 has 2 visible traces but no response to any x inputs at all. I have done visuals and set up adjustments to no avail. and am now looking at power supply measuring across the caps at top of the board as per manual. C836 is on the minus 12v rail. The cap is physically orientated to the opposite polarity of all the other power rail caps. so I measure with my dmm with positive lead to positive end of cap and I get plus 12v. I feel really stupid but am I right to assume that my dmm leads should correspond with the orientation of cap being measured in each case. If my approach is right the cap is inverted.....if my approach is wrong.....I could measure all the other caps in reverse and they would all be giving a negative voltage. Any guidance very much appreciated
Thanks

Jim
 

Offline Renate

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Sorry, you're going to have to link in a schematic.
Not everybody knows what C386 is, but I'm sure people will try if you give a hint.
 

Offline alsetalokin4017

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If the cap is "on the -12V rail" that means the cap's positive terminal is connected to the 0V reference level ("ground") and the cap's negative terminal is connected to the -12V supply. Right so far?

So if you just put your DMM across the cap, with the DMM's positive lead to the cap's positive terminal and the DMM's negative lead to the cap's negative terminal, you will read +12V, since the circuit's 0V reference level is 12 volts above the -12V rail. Right?

So what seems to be the problem?

The easiest person to fool is yourself. -- Richard Feynman
 


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