I bought a sparkfun 5V panel meter, one of the ones with needles.
I hooked it up directly to pin 3 and at duty cycle 255 it says 5V as expected.
Then I thought I better use a transistor (even though the coil is 7kOhms) so I hooked up some PN100 NPN transistor. The meter still read 5V.
At 128 duty cycle it shows a little less than 2.5V, with the NPN transistor. Curiously, if I drive it straight off pin 3, however, the meter shows like 4V.
How could that be? Why would the needle show a substantially higher (and apparently less correct) reading with no NPN transistor?