Re: Very hot hot zenerdiode in NAD T762



Jamie wrote:

Eeyore wrote:
Arfa Daily wrote:
"Eeyore" <rabbitsfriendsandrelations@xxxxxxxxxxx> wrote
Arfa Daily wrote:
"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@xxxxxxxxxxx> wrote

Well,
I have a theory..
If the Zener is in fact in series with the feed to the 7812
from the 22 volt source? May I suggest that maybe 22 volts isn't
the real voltage it should be? If this is the case, it would place
the zener in a high resistive state and it will get hot!..
The reason say this is because the 7812 (last time I checked) can
handle around 36 volts.
Since your Zener is 5.1 volts, that leaves 2 things in conclusion.

#1.
It really isn't being used in Series but in parallel with a feeder
resistor to be used as a reference! In which case, the feeder as
reduced
in size of the load from the circuit has been removed!.

#2
The 5.1 volt zener was picked to bring the Vcc source voltage down
a bit with in the safe operating range.

I would be willing to bet that it's suppose to be more than 22 volts.


Well I must say, Jamie, I am having some difficulty following those lines
of
reasoning.

The guy is totally clueless about hardware design.

Graham


Wot, Jamie or me Graham ?? :-)


Jamie.

I've never once seen a post where he 'gets it'. It never stops him pontificating
though. I understand he's a programmer. Explains a lot.

Graham

Graham, You better go back to the shitter and wipe your ass. Something
smells and I know it isn't me.

If only you had a clue, oh wet, you stopped at the birth of
cat whisker diodes and germanium transistors. I understand, to
complicated. Stay with your valves, they suit you fine.

I must say, your so far out of league you make me laugh. That is
the only reason I respond.

Btw, A couple of my engineer friends monitor this area, they think
you're a real peach.

They're as thick as you are ?

Your 'theories' above were totally pathetic btw.

Graham

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