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Wondering about this circuit
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RissViss:
Building a power supply, and wanted to power a fan off of the 19v 7amp laptop brick. Wanted to drop the voltage down to between 10 - 9 volts.

In picture 1 I used a 75 ohm 3w 5% axial resister and had a voltage of 10.37.
In picture 2 I used the 75 ohm resister and a Zener Diode 9.1v 5w axial and had a voltage of 10.00.

Is there an advantage to using the Zener over just the resister?
And any other info would help.
RissViss:
extra pics
StillTrying:
"In picture 1 I used a 75 ohm 3w 5% axial resister and had a voltage of 10.37.
In picture 2 I used the 75 ohm resister and a Zener Diode 9.1v 5w axial and had a voltage of 10.00."

You must have the zener the wrong way around.

Is there an advantage to using the Zener over just the resister?

The voltage at the fan would be more constant,  if the fan needs a high start current the volt drop across the resistor can sometimes be enough to stop it starting.
RissViss:
When I flipped the zener it was reading around 5 volts

When I used a 100 ohm 1/4 watt resister in place of the 75 the zener was right on the 9.1 volts, but the resister got hot.

RissViss:
could i put the 100 ohm resister after the zener and lower the temps on the resistor.
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