I began this lab by first forking and then cloning the repository 2012-Physics-308L-Lab-8-Transistors from Dr. Koch. Within the downloaded repository one could find the PDF file for “Lab 4: Transistor Circuits” from Panitz.
Transistors as Diodes
Our first task was to measure the resistance of the different components of the 1N3904 Transistor. A diagram of one can be seen below.
B:C Junction – 2.812 kohm
B:E Junction- 2.957 k ohm
When the leads were reversed the current would not flow and this clearly demonstrated the behavior of transistors as two diodes in series.
Transistors as Switches
For the first day of this lab we simply followed the directions for the part 2 of the Panitz lab 4.
We constructed the following circuit.
Daq board #121
Issues with several transistors left at station. When constructing the circuit the LED would fail to turn on
board # error
restarted LabView and error no longer occurred.
pic 2: w/ 10k ohm transistor
pic 3: off
pic 4: on
18.17 mA across LED while on (parallel) (incorrect)
10.63 mA ascross LEd while on series Correct
0 mA cross LED while off
current to base.
w/ 10 kohm resistor at A to ground .99 mA
w/ out 10 kohm resistor .50 mA (correct b/c did not need because DAQ board corrects itself)
Bad Ass Part
From now on 10 kohm resistor is disconnected
given rise time 35 ns
moved resistor w/ purple 270 to end where emitter goes to ground
red wires channel 2 (e-c)
orange wires channel 1 (switch)
(green to DAQ)
56 ns (within order of magnitude)
change probe to 1 x andcorresponding in osc
probe on channel 2 changed from 10x to 1x. Had to lower volts/div but reading that had similar level off was generated.
zoomed in and rise time was anout 36 ns