Circuit Board Component Abbreviations:

Incidentally, the standard which defines these designations was originally
ANSI Y32.2-1975, which has since been withdrawn and replaced with IEEE
315-1975.

RP: Resistor (Resistor Pack?)
R: Fixed Resistor
RN: Resistor Network
RV: Variable Resistor
C: Capacitor
L: Inductor
T: Transformer
D, CR: Diode
DL: Multisegment Display
Q: Transistor
U, IC: Integrated Circuit (IC)
X, Y: Crystal
F: Fuse
S, SW: Switch
J, P: Connector (J = jack/socket (female), P = plug (male))
JP: Jumper
B, BAT: Battery
M: Modular Subassembly, Daughterboard
FL: Filter
KB: Keyboard