FX 146
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FX-SERIES TRANSCEIVER GLOSSARY
The following is a deliberately INFORMAL collection of:
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Technical terms useful to know in understanding your FX- transceiver
design.
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Acronyms (phrases expressed by first letters of words: example: PLL
= Phased Locked Loop)
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Selected Electronics Industry "jargon"
Any of these words or expressions might be used in this instruction manual
or in conversation related to your FX- transceiver, either with other hams or
with Ramsey technicians. These descriptions or notes for a very few terms
certainly are not an "electronics dictionary," but the author/compiler hopes
that they might enhance your grasp of the concepts and language that he
has seen as useful in building and using this transceiver. For more detail,
PLEASE study the introductory part of each Assembly Stage.
ADDER
= Anybody who can add can be called an "adder." If we delegate
such work to electronic devices, the most fundamental digital operation after
being in a binary high or low (on or off) state is to be able to find the sum of
such states from two or more sources. The BINARY ADDER performs this
function. See also: BINARY.
AFSK
= "Audio Frequency Shift Keying." [SEE: "FSK"] In short, this is a
very popular form of data transmission.
AXIAL-LEAD
= Wires stretch out from two opposite ends of a part instead of
from one end, i.e. along the "axis" of the body. For example: L20.
BA-
= Manufacturer's PREFIX for PIN-type diodes.
BASIC
= "Basic." We're talking about the one computer programming
procedure that should make sense to ALL computer owners. If any further
explanation is needed, visit a library or computer dealer.
BB-
= Manufacturer's PREFIX for VARACTOR diodes.
BINARY
= the number system based on the two values of 0 and 1. Here are
all the tables that we need to memorize:
0 + 0 = 0 0 + 1 = 1 1 + 1 = 0 and carry 1 to next
position.
BOARD
= Generally refers to "PC board" or "printed circuit board."
BUFFER
= An electronic circuit stage, a sort of "referee" that tells its input
and output not to mess with each other.Think about such a task! It may also
provide amplified output of the incoming signal.
CASCADE, cascading
= combining two or more identical circuit elements or
components for improved effectiveness.
CARRIER
= Transmitted RF signal that is NOT "modulated." It is heard as a
steady tone on BFO-equipped receivers or as a powerful silence (i.e. over
riding all background noise or hiss) on FM receivers.
FX-146
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finish or review your work.
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G1a. Insert the 28-pin DIP socket for U6 into its PC board position and
slightly bend the 4 outermost pins to hold it in place.
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G1b. Examine the solder side and verify that ALL 28 pins are extended
into their respective holes.
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G1c. Press the socket squarely onto the board, solder the 4 corner pins,
check for proper seating, then solder remaining pins.
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G2. Install U6, MC145152, checking that all pins are fully seated.
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G3. Install oscillator crystal Y2, 10.240 MHz. Be sure it is firmly seated
on the board, then solder.
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G4. Install C87, 39 pf.
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G5. Install C80, 39 pf.
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G6. Install R38, 10K (brown-black-orange).
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G7. Identify C81, a 35 pf. trimmer capacitor. (Trimmer caps have 2
prongs; trimmer pots have 3.) Press it in place flat on the PC board.
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G8. Solder C81's two connections.
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G9. Identify and install U5, the LM358 dual op amp IC. Be certain to
orient the notched end as pictured on the PC board.
OBSERVE CORRECT POLARITY FOR THESE CAPACITORS:
Due to size constraints, the silkscreened "+" markings for these electrolytic
capacitors may not be apparent on the circuit board. Be sure to check the
parts diagram for proper orientation in placement.
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G10. Install C70, 2.2 uf. electrolytic.
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G11. Install C67, 2.2 uf. electrolytic.
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G12. Install C96, 4.7 or 10 uf. electrolytic.
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G13. Install C90, 2.2 uf. electrolytic.
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G14. Install C92, 2.2 uf. electrolytic.
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G15a. Insert U7, type 74HC283 IC with its notched end correctly
oriented. Solder the 4 outermost pins.
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G16a. Insert and solder U8 as in step G15a.
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G17a. Insert and solder U9 as in step G15a.