CETa Exam questions and answers
Hartley Oscillator ✔✔Operates Class A or B when purity is primary concern. Operates Class C
when efficiency is important. Uses split inductor in LC tank circuit for Frequency Determining
Network.
Colpitts Oscillator ✔✔Most widely used because of stability. Uses split capacitor in tank circuit
with a tunable inductor for adjusting frequency.
Crystal Controlled Oscillator ✔✔Most stable and accurate type of oscillator.
LED ✔✔Need about 1.6 volts forward bias to produce light. Draw around 10 milliamps of
current.
Photodiode ✔✔Resistance decreases when exposed to light, allowing current to flow in direct
proportion to the amount of light beamed onto it. Respond instantly to light.
Phototransistor ✔✔Has increased sensitivity to light and uses fast response speed with higher
current.
Photocell ✔✔Light-controlled variable resistors with a wide resistance range.
Photovoltaic Cell ✔✔Convert light energy into electrical energy, with each producing about half
a volt.
, Optical Coupler/opto-isolator ✔✔Couple AC signals or pulses while completely blocking any DC
component. A low current device that can be used to trigger high current components such as
SCR's and triacs.VGA ✔✔640 x 480
256 Colors
15 Pins
SVGA ✔✔800 x 600
256 Colors
15 Pins
XGA ✔✔1024 x 768 or 1366 x 768
16 mil, HD Colors
15 Pins
Widescreen ✔✔1280 x 720 or 1920 x 1080
DVI or HDMI Connectors
Random Access Memory ✔✔RAM
Read Only Memory ✔✔ROM
Programmable Read Only Memory ✔✔PROM
Electrical Programmable Read Only Memory ✔✔EPROM
Hartley Oscillator ✔✔Operates Class A or B when purity is primary concern. Operates Class C
when efficiency is important. Uses split inductor in LC tank circuit for Frequency Determining
Network.
Colpitts Oscillator ✔✔Most widely used because of stability. Uses split capacitor in tank circuit
with a tunable inductor for adjusting frequency.
Crystal Controlled Oscillator ✔✔Most stable and accurate type of oscillator.
LED ✔✔Need about 1.6 volts forward bias to produce light. Draw around 10 milliamps of
current.
Photodiode ✔✔Resistance decreases when exposed to light, allowing current to flow in direct
proportion to the amount of light beamed onto it. Respond instantly to light.
Phototransistor ✔✔Has increased sensitivity to light and uses fast response speed with higher
current.
Photocell ✔✔Light-controlled variable resistors with a wide resistance range.
Photovoltaic Cell ✔✔Convert light energy into electrical energy, with each producing about half
a volt.
, Optical Coupler/opto-isolator ✔✔Couple AC signals or pulses while completely blocking any DC
component. A low current device that can be used to trigger high current components such as
SCR's and triacs.VGA ✔✔640 x 480
256 Colors
15 Pins
SVGA ✔✔800 x 600
256 Colors
15 Pins
XGA ✔✔1024 x 768 or 1366 x 768
16 mil, HD Colors
15 Pins
Widescreen ✔✔1280 x 720 or 1920 x 1080
DVI or HDMI Connectors
Random Access Memory ✔✔RAM
Read Only Memory ✔✔ROM
Programmable Read Only Memory ✔✔PROM
Electrical Programmable Read Only Memory ✔✔EPROM
