Hmm. Offhand, here's a... 2N2102, nice TO-39 can. Setup:
9.76V supply
100 ohm series resistor to E
B = GND
C = open
E measures 7.54V (rising slowly as it warms up).
C measures -380mV, also rising slowly (i.e. towards zero) as it warms up.
C shorted, I measure -4uA. Hey, not bad!
Presumably, leakage shorts out the photocurrent (or free charge current, whichever it is, I forget exactly) as it heats up, so the efficiency of this mode drops quickly, much as solar panels do.
With a 10k pullup from +9.76V to C, I measure 9.71V... or more precisely a drop of 38.8mV. So, 3.88uA, consistent with the shorted measurement; seemingly less, but it's only a 5% resistor.
Collector current drops to -0.01mV (over 10k) when the emitter is open-circuited. (Meter is fluctuating between -0.02mV and 0.00 when shorted. This is the Hi-Z range, no loading on the circuit. Not that it would matter out of 10k.)
With a 1M pullup, it still measures +/- 0.01mV. Dang, this must be a nice transistor. (Brand name Central Semi, yay?)
With a 10M pullup and a 22nF bypass cap in parallel with the resistor (just in case there's rectification here?), it's reading 0.14mV, a whopping -- 14pA? Fuck me, that's damn good for a BJT, especially this size?
And, with the transistor removed from circuit, it's 11mV drop. So, plus or minus a lot of leakage through the breadboard, or the meter itself. (Meter with just the 10M and no ground or supply connection reads -0.07mV.)
Gosh... I slide my be-socked foot across the wood floor and the measurement goes nuts...
![Laughing :-DD](https://www.eevblog.com/forum/Smileys/default/smiley_laughing.gif)
(Meter is just a BM235.)
Whelp... I'm sure you'll have much more noticeable results with a big fat power transistor, especially a sloppy one like 2N3055 (depending on age of the specimen..), or at higher voltages (9V is a far cry from the 120V rating of the 2N2102).
Tim