Ten-Tec SSB-CW-AM Instruction Manual page 118

FILTER-ACTIVE
FILTER-CERAMIC
FILTER-CRYSTAL
FILTER-HI-PASS
FILTER-LOW-PASS
FILTER-BANDPASS
FILTER-PASSIVE
FREQUENCY SYNTHESIS
frequencies are a crystal oscillator or the L-C oscillator where the frequency is
determined by coil (L) and capacitor ©. 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.
GROUND PLANE
electrically connected to DC and RF ground. In the 1254 receiver 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 antenna has a vertical radiating element, plus
four (or more) horizontal elements connected to RF ground, the horizontal elements
HIGH In solid-state logic circuitry, to say a given device pin or circuit point is at a
to the opposite state (LOW) or back again for some specific purpose is a fundamental
capability of the circuit.
IF (Intermediate Frequency)
frequency resulting from mixing an incoming signal with the signal from an LO within
the receiver. The Model 1254 has two IF's: 45 MHz and 455 kHz. Se also LO,
Mixer, Superhet.
JUMPER Any wire soldered to interconnect points in a circuit not otherwise
are short jumper wires in a resistor body painted with one black band.
L-C A tuned circuit made of inductor (L) and capacitor ©.
LOCAL OSCILLATOR (LO)
mixed with another signal such as antenna input. See SUPERHET.
LOCK The condition in a phase-locked-loop (PLL) in which all sections are
working together as intended and designed.
LOOP FILTER (See PLL). The output of a PLL phase detector is in the form of
pulses. The frequency of those pulses depends on the reference frequency. The loop
Filters are used in DC, Audio and RF
circuits. Understanding them is essential
electronics know-how.
ALL sections of a circuit board which are mechanically or
In any superheterodyne receiver, and IF is the
An oscillator in a superhet receiver whose output is
1254 Reference - 25