Why attend a kegger (when you can play with a megger)

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I've had this old Amprobe AMC 4 for a while
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I noticed on the low setting I can get some voltage readings either with leads and multimeter or multimeter leads across inserted resistor.
But at the two next higher settings I don't get anything 

Maybe I'm using or testing it wrong.

Anyhow I opened it up to have a look.

Testing at the what I presume is the secondary of a transformer I get about 400V AC 

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Beyond that I'm not coming up with much.

Thinking out loud here I thought maybe some generators are straight DC but I guess this one is AC and still has to be rectified? 

Anyhow I started eyeballing this (diode ?) and get some DC on the other side of it but not much. 
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Maybe it's not a diode because it has a band in each end idk.

Also I get like a 17v voltage drop across it.

 

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I'm thinking now the suspected diode is just one of those resistors without stripes (color coded bands) on it.

I'm in deep reflection pondering the likelihood that the AC is not rectified at all.  Like...dude there is no dc the megger uses ac for everything why are you looking for that which is not there.   

This would be a great time to meditate on the beaches of Tasmania 

Edit: nope it is supposed to generate DC
Get back to work

[g1]

What is the full number(s) on that diode-looking part?  What is the voltage rating on that cap?

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Yes sir thanks

Unfortunately I can't see much on the diode thingy

Best I can do is maybe 80400 

And a pic of the capacitater

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Also I was gonna point out these guys

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And that's when I found some diodes cleverly stashed 


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[Tassieviking]

You would not like the beaches of Tasmania at this time of year, it snowed like crazy some time in the last week I was told.
I don't know myself since I had my first ulcer, I should say ulcers last week and ended up in hospital after the ulcers dumped over half my blood into my stomach, take it from me its hard to think, breathe and you get very woozie when you loose that much blood. 5 days in hospital getting blood pumped back in and the ulcers stapled up and all is good now, sort of.(I'm up to 75% of my normal blood level).

Just check the diodes with a multimeter, those 0.1uF 630V capacitors don't look bad but you never know.

 

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Yes sir thanks

Hope you get to feeling better 

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Yes sir I did put the multimeter on each diode and cranked

Three of four showed about 0.5-0.8 voltage drop

But one consistently showed 2 volts or better

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However all showed good diode check

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I know it's not much to go on maybe the diode is not to blame but something up or downstream of it.