Ramsey Electronics FX Series Manual page 41

CCW = see CW below.
COR = "Carrier Operated Relay," a switching circuit activated by the detection
of a carrier signal in a receiving circuit.
"CW" = TWO common meanings in electronics: "Continuous Wave" for the
communicating of Morse code signals, or "Clockwise" to designate a point on
a variable control. "CCW" therefore means "counterclockwise."
DECIMAL = in computer or programming context, "decimal" refers to counting
by tens, our traditional way, in contrast to your computer's binary (counting by
1's and 0's), or the hexadecimal system (counting by 16's.) See "N" and
BINARY.
DIP = "Dual Inline Package," referring to IC's and their sockets or any other
component ("DIP Switch," etc.). The "line" refers to rows of PC-board or
perfboard holes that are 0.1" apart. "Dual" means two rows. Therefore "SIP"
would mean a SINGLE row device.
DISCRIMINATOR = FM terminology for "detector." See: FM.
DUAL-MODULUS = as in dual-modulus prescaler or divider: a circuit which
divides a frequency by two different ratios depending on pin selection, for
example: 64 or 65. (See: PRE- SCALE)
FILTER-ACTIVE
FILTER-CERAMIC
FILTER-CRYSTAL
FILTER-HI-PASS
FILTER-LOW-PASS
FILTER-BANDPASS
FILTER-PASSIVE
FM ("Frequency Modulation") = Changing the transmitter frequency in exact
pace with speech or sound variations.
FREQUENCY SYNTHESIS = To "synthesize" anything is to create an
imitation or simulation from something else. The "basic" ways for generating
useful RF frequencies are a crystal oscillator or the L-C oscillator where the
frequency is determined by coil (L) and capacitor (C). However we can
process the output of an L-C oscillator through digital circuitry to simulate
many different, precise crystal-like frequencies, using only one crystal as a
reference standard. See also PLL, PHASE DETECTOR, VCO.
FSK = "Frequency Shift Keying." TRUE FSK actually moves the RF
frequency (transmitted and received) from one pre-determined point to
another, in contrast to "AFSK" (Audio Frequency Shift Keying") where the
transmitted signal remains steady and all shifting is done by audio tones.
GROUND-PLANE = ALL sections of a PC-board which are mechanically or
electrically connected to DC and RF ground. In the Ramsey FX design, almost
ALL of the top or upper side (component side) of the board is a groundplane.
The term is also used in antenna design: if your 2M or 1.25M antenna has a
vertical radiating element, plus four (or more) horizontal elements connected
Filters are used in DC, Audio and RF
circuits. Understanding them is essential
electronics know-how. The Radio Amateurs'
Handbook covers the subject of filters very
well.