B&K 0-3A Power Supply User Manual


 
21
APPLICATIONS
GENERAL
The Model 1735A power supply has a very wide variety of
applications in electrical and electronics servicing, engineering
laboratories, manufacturing and testing facilities, schools, and
home hobbying. The power supply output is fully adjustable from
0 to 30 volts and 0 to 3 amps. This flexibility makes them
suitable for most applications requiring a dc power source.
ELECTRONICS SERVICING
Most electronics troubleshooting and repair is performed on a
test bench. This power supply can provide the dc power source to
operate a module or circuit board on the test bench when it is
removed from its parent equipment. It can be used to power
portable, battery-operated equipment and check the effect of low
battery voltage. It can power vehicular equipment such as tape
players, auto sound systems, CB radios, etc. on the test bench.
Most automobiles and other vehicles use 12-volt electrical
systems. Although the electrical system is normally referred to as
a 12-volt system, actual battery voltage when fully charged is
approximately 14 volts. The power supply may be set to 14 volts
for servicing equipment from vehicles with 12-volt electrical
systems. Some trucks use a 24-volt electrical system; bench
testing of equipment from these systems should be performed at
28 volts.
Some servicing applications require the injection of a variable
dc voltage for certain tests, such as checking the effect of AGC
bias in a television receiver. This requires an isolated dc power
supply, such as the Model 1735A.
The equipment being tested may contain its own power supply
and operate from ac power. A dc voltage may already be present
in the circuit. One polarity of the power supply output is floated
to an appropriate point in the circuit, such as the emitter of a
transistor. The other polarity of the power supply output is then
applied to another point in the circuit, such as the base of that
transistor. Varying the power supply voltage then varies the dc
bias on the stage, and the effects may be noted. A series limiting
resistor is often used to protect the circuits from overdissipation.
ELECTRONICS MANUFACTURING
In electronics manufacturing facilities, the power supply is
often used as a dc power source while testing and adjusting
modules, subassemblies, and complete units in the production
and assembly area or in the quality control area. The instrument
can be used in incoming inspection as a dc power source for
testing purchased components and subassemblies.
This power supply is particularly well suited for manufacturing
applications because of its ease of operation and its continuous
duty rating. When load current or total power dissipation are
among the main characteristics to be measured, the total load
current and voltage are easily displayed on the LED displays. The
current limit can be set so that all units which do not meet the
load current specification will cause the CC indicator to light,
and the unit can be rejected.