- performance range
- periapis
- penetration CRT
- penetration current
- pentode
- percentage availability
- perfect code
- performance data
- perigee pass
- perigee stage
- period
- period doubling
- period pulse
- periodic antenna
- periodic noise
- periodic perturbation
- periodic pulse
- periodic refresh
- periodic signal
- periodic time
- peripheral appointment
- peripheral file
- peripheral limit
- peripheral management
- peripheral storage
- periscope antennal
- permissible interference
- permit account
- permit packet
- permitted service
- persistence
- Persistence Time
- personal call
- personal system
- periodicity
- peripheral buffer
- peripheral driver
- peripheral failure
- peripheral ghost
- peripheral module
- peripheral processing
- periscope aerial
- periscope antenna
- permitted basis
- persistence characteristic
- personal identification
- perturbation torque
- petty cash
- phantom group
- phase alignment
- phase demodulator
- phase detection
- phase detector
- phase distribution
- phase encoding
- phase equalization
- phase equalizer
- phase front
- phase hunting
- phase instability
- phase interference
- phase jump
- phase locking
- phase loss
- phase margin
- phase modulation
- phase noise
- phase recording
- phase regulation
- phase relationship
- phase response
- phase reversal
- phase scintillation
- phase shift
- phase stability
- phase state
- phase time
- phase transfer
- phase tuning
- phase uncertainty
- phase-encoded
- phase-shifted
- phased array
- phasing error
- phasing matrix
- phasing network
- phasing time
- phone user
- phosphorescent material
- photo-conductor
- photo-multiplier
- photoelectric amplifier
- photoengrave
- photoetching technique
- photon
- photoreceptor
- photoresist coating
- photosentor
- phototelegraph communication
- picture definition