I am building a JCM900 Marshall guitar amplifier from a schematic and I have
a parts list that I am not sure about, specifically :

Q1: Potentiometer Question -- I notice there are 8 potentiometers. There
are labelled VR1 - VR8:

VR1 - A1M
VR2 - A1M
VR3 - A1M
VR4 - A1M
VR5 - B220K
VR6 - B22K
VR7 - B220K
VR8 - B22K

Am I correct in assuming that A1M means Audio 1 MegaOhm ? Audio meaning
logarithmic ?
Also what does 'B' mean in VR5-VR8 ?
Does B mean linear ?

Q2: Capacitor Question -- I have a list of several Caps

C08 - RAD 30000uF / 30v*
C09 - RAD 33uF / 350v*
C11 - 22uF / 50v (NO POLARITY)*
C10 - RAD 33uF / 350v*

What does RAD mean ?

Any help greatly appreciated

Stephen Mew