- PAND
- Presidential Audio News Distribution A service offered by ABC Radio
providing audio from the President's travels within the continental United States. Usually
at least Rood quality, sometimes a wideband second subcarrier on
their TV feed. Offered as a premium service to subscribers of WAND.
Here's more information about PAND.
- PBS
- The Public Broadcasting Service. The program distribution service for
Public Television produces no programming itself.
- PCM
- Pulse Code Modulation A digital coding scheme using a fixed sample rate
and linear coding of the sample voltage.
- PEGAD
- Permission Granted To Add AT&T parlance
indicating that one telco circuit user is permitting another one to be connected to his
circuit or his network. Usually used to temporarily add a new station to an existing radio
or television network, or to allow one network to pick up the programs of another, such as
pool feeds. A Program Operations Order or Switch Order specifying that we are to add on to
another radio or TV network must specify the person at the other network that we got
permission from and that persons telephone number. PEGADs can only be issued from NPR (for
others to use our programming) by a person of authority, usually in Operations or
Programming.
- PGCU
- Program Circuit Unit Equalized (or equalizable) pairs of wire between
any two points (usually one of which is a telco central office) which can be used to
construct a local channel.
Appears to be a concept on the way out. The need for last
minute Program Circuits is rapidly being filled by ISDN service,
which can achieve similar results at less cons.
- PL
- Private Line Also called a "ringdown", Permanent, two-way telephone talk
circuit between two points. The telephone instruments at both ends need not be equipped
with a dial as the phone at one end rings as soon as the phone at the other end is picked
up. Also abbreviated "PLAR" which means private line with automatic ring.
- The Motorola term for tone coded squelch. A sub-audible tone that is transmitted
whenever the PTT button is pressed. PL is generally used when multiple users share one
channel. The receivers in a system will only make audible signals transmitted by users in
that same system. We use a PL of 67 Hz.
- POC
- Program Operating Center Also called a Servicing Test Center or Toll
Test Board or "Program". Largely a thing of the past.
- POL
- Program Operating Level Also called Customer Level or Plant Level. The
standard level in any system above which only program peaks exist. This level is +8 dBm
into 600 ohms for most broadcast plants and for Telco. It is +4
dBm for the NPR plant and for the Public Radio Satellite System. It is
zero VU in all systems.
- POTS
- Plain Old Telephone Service. What Alexander Graham Bell invented, the
ability to dial up and talk to anyone else. These same channels have are used for FAX and Modem communication as well as
normal voice transmission.
- Pre-Emphasis
- The audio is passed through a non-linear amplifier before transmission and after
reception. This is a mirror-image system that boosts the high frequencies at the
transmitter and then returns them to normal at the receiver. It also has the effect of
lowering the noise picked up in the transmission system that tends to be of higher
frequencies. The drawback is that any high-level high-frequency audio will cause the
system to overload.
The amount of pre-emphasis is usually expressed as a time constant,
with twenty-five and seventy-five microseconds being the most common. Regular FM
broadcasting uses seventy-five microsecond pre-emphasis.
- PRI
- Primary Rate Interface A high capacity ISDN
digital service delivering 1.544Mbit of data to the customer, sounds a little bit like a T1 doesn't it? This service is divided into twenty-three 64Kbit Bearer Channels and one 64Kbit Data Channel. Like the BRI, the B
channels are used for communications services while the D channel is used for call setup
and other overhead.
- Public Radio International, formerly APR, American Public Radio
A programming service for Public Radio Stations based in St. Paul with NO production or
distribution facilities. PRI offers both NEWS and Cultural programming produced at various
locations around the country. Distribution is on the PRSS and two
additional channels on the same transponder.
Their News offerings
include MonitoRadio produced by the Christian Science Monitor, Marketplace
produced by KUSC, and a 24 hour feed of BBCWorld Service uplinked
in Washington.
PRI offers both a Jazz and Classical overnight service as well as a number of
high-profile Music/Entertainment shows; A Prairie Home Companion produced by
Minnesota Public Radio, Mountain Stage produced by West Virginia Public
Radio, Wha'da Know? produced by Wisconsin Public Radio, just to name a few.
PRI is both a competitor to NPR Programming and a customer of NPR Distribution.
- Program Circuit
- A telco circuit that carries audio signals, usually intended
for broadcast. The circuit can be copper or carrier, or a combination of the two. The class of service, determined at installation, determines
the resulting quality of the audio.
- protocol
- The method of communications used between any two devices, how they talk. This usually
includes hardware or physical specifications as well as software.
- PRSS
- The Public Radio Satellite System Formerly twelve channels of wideband
analog audio on transponder three of Galaxy 4 managed by NPR Distribution for Public
Radio. These channels were maintained for all CPB Qualified
Public Radio Stations. This was the home of NPR programming as well as offerings from PRI and other suppliers.
This analog system was replaced by an ISO/MPEG
Level II encoded digital system in January 1996. There are now twenty-four stereo carriers
available on two transponders of Galaxy 4. All service is 128 Kbits per channel using a
secure transmission scheme. Equipment was built by Comstream with audio coding
subcontracted to CCS.
- PTT
- The Postal, Telephone & Telegraph The phone company in most parts
of the world, owned and operated by the national government. Many of these entities are
now being privatized
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