From QRZ.Com, the Icom handout, and Part 97 Of The FCC Rules -
Ham Radio Glossary - An overview of amateur radio terms.

PA
Power Amplifier

Packet
A digital mode that sends "packets" of data between stations. Since it
checks each packet received with what was sent, packet communications
are error free...what is sent is what is received. This can mean the
difference with traffic concerning 10 or 100 casualties. While there
are not as many packet bulletin board systems (PBBS's) now, as compared
to years ago, many hams still enjoy this mode of the hobby. It requires
a rig, a TNC, and a computer. VHF Packet typically is at 1200 baud, while
HF packet is at 300 baud.

Parawatch
See Dualwatch.

Paddles
Short for "Morse Code Key", one that contains small paddles that are
tapped in order to produce semi-automatic Morse Code (when connected to
a "keyer").

Part 97
Portion of the FCC rules relating to amateur radio.

Patch
Short for "Phone Patch".

PBT
Pass Band Tuning. A function electronically reducing interference by
narrowing IF bandwidth.

PEP
"Peak Envelope Power"; used to measure power output of an single sideband signal. RF power at maximum amplitude.

Phone Patch
Device allowing audio from a telephone line to be placed in the audio
circuits of a transmitter/receiver (thanks to WD5CTQ).

Physician
For the purposes of the Part 97 Rules, a person who is licensed to practice
in a place where the amateur service is regulated by the FCC, as either a Doctor of Medicine (MD) or a Doctor of Osteopathy (DO).

P-N Junction
A P-N junction (or N-P junction) is formed by creating two substrate
materials of P type and N type on a semiconductor. P type means it is
doped with "free holes" (electron depletion) and the N type is doped with electrons. Of course by physics, the free holes and free electrons would
like to neutralize each other. A diode is formed with a P-N junction. Basically, when you have a NPN transistor, you have two junctions ... an NP junction between the collector and base, and a PN junction between the base
and emitter. Vice-versa with a PNP transistor. How you bias those junctions controls how the transistor works.

Pink Ticket
FCC Notice of Rule Violation

PL
"Private Line", Motorola's trademarked name for CTCSS.

PLL
Phase Locked Loop. Circuit to synthesize the different frequencies a
radio will operate on.

PM
Phase Modulation or Pulse Modulation

Pocket Beep
Beeping function when a specific signal is received.

PNP
See "P-N Junction".

Priority Watch
Reception mode, which by a selected frequency is always periodically
checked when VFO is set to a different frequency.

PSK31
A digital mode which is rapidly growing in popularity; utilizes phase shift keying (PSK) which is transmitted at 31 baud (speed). For more information, please see http://www.psk31.org. While it does not have "error correction",
it can detect signals below the noise floor, using such programs as
DigiPan and MixW.

PTT
"Push to Talk"; a button on a microphone or on the side of a handheld radio which activates the transmitter.

PWR
Power
--- SBBSecho 3.20-Win32
* Origin: The Thunderbolt BBS - Little Rock, Arkansas (1:2320/33)