Week 1
Week 1Experiment 1 Breadboard BasicsThe goal of Experiment 1 is
for you to identify on the breadboard of the ANDY board:which of
the rows of pins are connected (shorted) together andwhich of the
set of pins in columns are connected together so that you will be
able to construct the circuits properly in the experiments that
follow.Breadboard Basics
ANDY boardThe breadboard on the ANDY board is the white section
with the rows of pins. It is used to hold components and to allow
easily wiring between the power supplies on the ANDY board to the
components and from the component to component to form a
circuit.The squarish holes are where wires or the legs of your
components are inserted. Inside each hole is a set of leaf springs
that clamp on to the wire or end of the component inserted into the
hole. This is the back surface of the breadboard, which one of the
ECE lab staff removed from the board similar to the ANDY board.Some
metal strips run horizontally and some run vertically. These strips
create a low resistance connection between the sets of square holes
along the metal strip to allow you to easily connect ends of
components together without running wires between them.Wires are
used to make jumpers between metal strips.Maximum frequency of
operation is 4 MHz, due to parasitic capacitance
Typical Pattern of Connections. Your job in Experiment 1 is to
determine which set of holes in specific columns and rows are
connected by these metal strips on the ANDY board.
An instrument that is used to measure:DC voltage and DC
currentAC voltage and AC current (RMS values)Resistance up to 200
MWContinuityCommonly used to determine polarity of
diodesCapacitance at 20 kHzFrequency of a sinusoidal voltageLow
frequency hfe (or b) of a transistorTemperatureMeasured with
thermocouple probe.
MY-64 Digital MultimeterChange the battery in the multimeter.The
current 9V battery was inserted when the multimeter was
manufactured. The battery has about a 1 year shelf life.Errors in
measurements can be greater than 10% when the battery voltage is
low.This is greater than the measurement error allowed in the
grading program.Failure to replace the battery with a new one may
cause you to lose points on your post-validation report.There
should be a new battery in your parts kit. Directions are available
online at
http://filebox.ece.vt.edu/~LiaB/Equipment/DMM/Changing_Battery.pdf
Before you use the DMM
Resistance measurements can be made directly using a digital
multimeter (DMM).The probes are inserted into the V/W/T plug or
jack (red probe) and the COM jack (black).Note that the dial on the
meter is positioned at the 20k mark within the W measurement
region.
Digital Multimeter
The probes that come with the DMM have tips that are too large
to fit into the holes on the ANDY board breadboard.Do not force
them into the holes as this will damage the leaf springs within the
holes.There are a set of banana jack probes in the probe kit that
is offered by Electronix Express that have smaller tips, which you
can use instead.Or you can use a small length of wire wrapped
around each of the original probe tips that you then insert into
the holes.Probes
Banana jacksSet the dial to the maximum resistance value.When
there is only air between the tips of the red and black probes, the
reading on the DMM is in the overflow condition as air is an
insulator and the resistance of air is greater than 200 MW.A 1 off
to the left with no other digits displayed.When there is a very
conducting material placed between the two tips, the measurement
should be 0.00, indicating that the resistance of the material is
much less than 200 MW.You should rotate the dial to a lower
resistance range until you either reach the lowest range or an
overflow condition is indicated. In the first case, you should
record the measurement.In the latter case, you should set the range
to the next highest setting and then record a
measurement.Resistance MeasurementsFollow the pattern described in
the laboratory manual to map the position of the metal strips that
connect sets of holes (pins) on the ANDY board breadboard.Should
you find that the minimum resistance that you measure between pins
that are connected by a metal strip is greater than 5 W, you may
have a bad breadboard.Very rarely, the metal strips shift in
position during shipment.Contact one of the the OpEL GTA
immediately and show the GTA the measurement. If the GTA determines
that you have a bad board, he will trade your old ANDY board for a
new.Potential Issue
