C -Capacitance or capacitor       
CAD -Computer aided design

CAM -Computer aided manufacture    
CATV -Cable TV

CB -Common base configuration
CB- Citizen's band

CC -Common collector                
CE-Common emitter
cm –Centimeter                          
cmil -Circular mil

CPU- Central processing unit      
C (Q)-Coulomb

CR cr -Junction diode                 
CRO- Cathode ray Oscilloscope
CRT -Cathode ray tube               
C_T -Total capacitance
cw -Continuous transmission
E DC- or Erms Difference in potential

e -Instantaneous difference in potential 
ECG- Electrocardiogram

ECL -Emitter coupled logic         
EHF- Extremely high frequency

EHV- Extra high voltage              
ELF- Extremely low frequency

EMF-Electromotive force            
EMI-Electromagnetic interference
EW- Electronic warfare
G- Gravitational force
G -Conductance
G- Giga (10⁹ )
JFET-Junction field effedt transistor
L- Coil, inductance
LC- Inductance-capacitance
LCD- Liquid crystal display
L-C-R -Inductance-capacitance-resistance
LDR- Light-dependent resistor
LED- Light emitting diode
LF- Low frequency
L_M- Mutual inductance
LNA- Low noise amplifier
LO -Local oscillator
LSI- Large scale integration
L_T -Total inductance
N -Number of turns in an inductor
N-Revolutions per minute
n-Nano (10^-9)
N- Negative
NA- Nanoampere
NC- Normally closed
NCNo- connection
NEG, neg –Negative
NF-Nanofarad
nH -Nanohenry
nm- Nanometer
NO-Normally open
NPN- Negative-positive-negative
Ns- Nanosecond
NW- Nanowatt

THz-Terahertz
TM-Transverse magnetic
TR-Transmit-receive
TTL-Transistor-transistor logic
TWT-Travelling wave tube
TV - Television
W –Watt
X_C -Capacitive reactance
X_L -Inductive reactance
Y -Admittance
Z –Impedance
Z_in -Input impedance
Z_o -Output impedance
Z_p -Primary impedance
Z_s -Secondary impedance
Z_T -Total impedance
B -Flux density
BCD -Binary coded decimal

bfo -Beat frequency oscillator
BJT -Bipolar junction transistor

BW-Bandwidth
d- Deci (10^-1)

D/A or D-A-Digital to analog    
DC-Direct current
DIP-Dual in-line package            
DMM -Digital multimeter

DPDT -Double pole double throw
DTL-Diode transistor logic
DVM-Digital voltmeter
 – Frequency
FET-Field effect transistor

FF-Flip Flop    
fil -Filament
 

FM- Frequncy modulation    
f_r -Frequency at resonance
fsk -frequency-shift keying   
FSD- Full scale deflection
H- Henry
H- Magnetic field intensity
H -Magnetizing flux
h- hecto (10² )
h -Hybrid
HF- High frequency
hp -Horsepower
Hz -Hertz
I -Current
i -Instantaneous current
I_B -DC Base current
I_C -DC Collector current
IC- Integrated circuit
I_e- Total emitter current
I_eff- Effective current
IF- Intermediate frequency
I_max -Maximum current
I_min -Minimum current
I/O- Input/output
IR- Infrared
I_R- Resistor current
I_S -Secondary current
I_T -Total current
K- Coefficient of coupling
k- Kilo (10³ )
kHz- Kilohertz
kV- Kilovolt
kVA- Kilovoltampere
kW- Kilowatt
kWh-Kilowatt-hour
M-Mega (10⁶ )
M -Mutual conductance
MI -Mutual inductance
m- Milli (10^-3 )
mA-Milliampere
mag- Magnetron
max –Maximum
MF- Medium frequency
MH- Millihenry
MHz -Megahertz
min –Minimum
mm- Millimeter
mmf -Magnetomotive force
mW- Milliwatt
MOS -Metal oxide semiconductor
MOSFET -Metal oxide semiconductor field effect transistor
MPU- Microprocessor unit
MSI- Medium scale integrated circuit
mV –Millivolt
P- Pico (10^-12)
P- Power
p- Instantaneous power
P- Positive, also peak
PA- Public address or power amplifier
PA- Picoampere
PAL- Programmable Array Logic

 

PAM, pam- Pulse amplitude modulation
P_ap-Apparent power
P_av-Average power
PCB- Printed circuit board
PCM, pcm-Pulse-code modulation
PDM-Pulse-duration modulation
PF-Picofarad
PLD-Programmable Logic Device
PLL-Phase locked loop
PM- Phase modulation, also Permanent magnet
PNP-Positive-negative-positive
POT, pot-Potentiometer
P-P-Peak to peak
PPM-- Pulse-position modulation
PRF-Pulse repetition frequency
PRT-Pulse repetition time
Pw- Pulse width
PWM, pwm- Pulse width modulation
Q-Charge, also quality
q-Instantaneous charge
SCR-Silicon controlled rectifier
SHF-Super high frequency
SIP-Single in-line package
SNR-Signal-to-noise ratio
SPDT-Single pole double throw
sq cm- Square centimeter
SSB- Single sideband
SW-Short wave
SWR-Standing-wave ratio
SYNC, sync-Synchronous
UHF- Ultra high frequency
UHV-Ultra high voltage
UJT-Unijunction transistor
UV-Ultraviolet
V- Vacuum tube
V, v-Volt
v- Instantaneous voltage
VA- Volt ampere
V_av-Voltage (average value)
V_BE-DC voltage base to emitter
V_c-Capacitive voltage
V_CE-DC voltage collector to emitter
VCO-Voltage controlled oscillator 
VHF-Very high frequency
V_{In -}Input voltage
V_L- Inductive voltage
VLF- Very low frequency
V_m, V_max -Maximum voltage
VOM-Volt ohm milliameter
 V_out -Output voltage
V_p -Primary voltage
V_S-Source voltage
VSWR-Voltage standing wave ratio
V_T-Total voltage