Service manual
2
•
OTP
“One
Time
Programmable”
A type of (E)prom which can not be
erased.
•
P.C.
“Personal
Computer”
•
PD
“Phase
Detector”
This PLL pin provides a pulsed output
whose
average
voltage, after
filtering
and
smoothing, controls the frequency of the
VCO.
•
PGM
“
ProGraM”
A
suitable
voltage
pulse on this Eprom
pin will enter into an Eprom the code on
its output data pins,
according
to the
location
code on its input or address pins.
•
PLL
“Phase
Locked
Loop”
In this context, refers to an
Integrated
Circuit
which controls the frequency of
an
oscillator
according
to the "
Nt'
code
on its inputs.
•
Quartz
A
mineral
which is
transparent
to
light
and, more
importantly,
to
ultra-violet
light.
•
Regulator
A
device
or
circuit
which produces a
constant
voltage
output even if the input
voltage
varies.
•
Skip
...
see
“A”
channel.
•
Software
Refers to a microprocessor or
computer
program, rather than the
circuit
components themselves.
•
Switch
codes
The binary outputs of a
channel
switch.
•UV
Ultra
Violet
light
which is
invisible
to the
human eye and can be harmful.
•
Vcc
The IC pin which requires a
positive
supply voltage.
•
Vdd
The IC pin which is
connected
to
ground.
•
VCO
"Voltage
Controlled
Oscillator"
•
Vpp
The IC pin which must be
connect
ed to a
specified
voltage
in order to allow
programrning of the device.
•
Zener
A type of diode which produces a
specific
voltage
when current flows through it in
the reverse direction, that is, with the
anode more
negative
than the cathode.