- random fluctuations
- random irregularities
- random logic
- random model
- random quantity
- random search
- random uncertainty
- range
- range from
- rational expression
- rays space
- reaction control
- read screen
- rear lobe
- rebroadcasting chain
- receiver amplifier
- receiver demodulator
- receiver van
- receiving gain
- recession function
- recipient country
- reciprocal circuit
- reciprocal path
- recombination process
- reconfiguration
- reconstructed sample
- recorded programme
- recorded pulse
- recording amplifier
- recording channel
- recording day
- recording format
- recording medium
- recording system
- recover
- recovery point
- recovery procedure
- read-in
- readiness circuit
- reading beam
- readout device
- real image
- rebroadcast transmitter
- recalibration
- recall signal
- receive crystal
- receive signal
- receiver
- receiver antenna
- receiver desensitization
- receiver end
- receiver gain
- receiver group
- receiver noise
- receiver output
- receiver radiation
- receiver selectivity
- receiver-transmitter
- receiving antenna
- receiving site
- reception conditions
- reception mode
- reception quality
- recombination line
- recombining process
- reconstituted frequency
- reconverter
- recorded announcement
- recording instrument
- recording level
- recording manometer
- recording noise
- recording sheet
- recording studio
- recovery package
- recovery routine
- rectangular pulse
- rectangular signal
- rectification
- rectified signal
- rectilinear generator
- rectilinear propagation
- recurrence expenses
- recurrent pulses
- recursive analysis
- recursive filtering
- recursive routine
- red laser
- red signal
- reduced carrier
- rectifying diode
- rectilinear antenna
- recursive function
- red out
- reduced model
- redundancy reduction
- redundant bit
- reed contact
- reentry
- reference beam