Small Wonder Labs PSK-20, Instructions Manual

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Small Wonder Labs

PSK-20 Transceiver Kit 03/09/10

2000 4
steps as you complete then, or make other notes and
still keep the original clean. )
REFERENCE DESIGNATORS:
Each component is uniquely identified with a
reference designator. Bypass capacitors are identified
as C101 and up. Reference designators are shown in
blue on the schematic pages.
C
OMPONENT IDENTIFICATION
:
•
Resistors and RF chokes
This manual describes the color coding for all resistors
and RF chokes. Only the first three bands are
described, the fourth band is a tolerance code, typically
gold (=5%) and is not listed. All resistors are 1/4W 5%
carbon film types, RF chokes are also an axial (leads
out of each end) component but are notably larger.
•
Capacitors:
Here's the general rule for capacitor nomenclature:
If 3 digits are printed on the capacitor, the first two are
significant figures and the third is a multiplier.
Examples:
'471' = 47 x 10
1 =
470 pF
'103' = 10 x 10
3 =
10,000 pF = .01 uF
Letter suffixes: J=5%, K=10%, M=20%.
Please: If you're looking for a '104' monolithic cap,
be sure to inspect both sides of the caps before
concluding we gave you the wrong value!
Monolithic caps:
The printing on these parts is tiny! I'd highly
recommend using a magnifying glass to verify
component values before installing them.
If these parts are supplied with a 0.1" (2.5mm) lead-
spacing for installation in a board hole-spacing of 0.2"
(5 mm), bend the wire leads gently to spread the
spacing . Avoid sharp bends right at the wire-lead exit
from the epoxy case; this may cause component
damage/failure.
•
Extra information on components
There's often extraneous information marked on
components. Examining a sample IC, I find
"MC1458P1 KKJK 8949". You care only about the
'1458' or other markings I've specified
If I've specified
a capacitor '104' and you find the correct number of
parts, but marked "104M', for instance, those are
them! 'Dr. Suess' referred to 'Calculatus Eliminatus' -
a wise man indeed!
IF Transformer (T1):
Although not illustrated on the schematic for reasons
of drawing clarity, T1 contains an internal capacitor
within its base. Do not remove this capacitor.
PARTS LIST
Quantity Reference Designator Value Description Markings or Ident.
1 C35 4.7 pF NPO disk cap '4.7'
12 C1,C8-C13,C25-C29 22 pF 5% NPO disk cap '22'
2 C44,C48 4-20 pF 6mm trimmer cap Red or Red/Black
1 C7 33 pF 5% NPO disk cap '33'
3 C17,C45,C46 47 pF 5% NPO disk cap '47'
4 C3,C34,C36,C47 100 pF 5% C0G cap, monolithic '101' or '101J'
4 C38,C40,C43,C51 150 pF 5% C0G cap, monolithic '151' or '151J
2 C49,C50 180 pF 5% C0G cap, monolithic '181' or '181J'
2 C41,C42 330 pF 5% C0G cap, monolithic '331' or '331J'
3 C4,C33,C37 470 pF 5% C0G cap, monolithic '471' or '471J'
26 C2,C5,C6,C16,C30-C32,
C101-C106,
C108-C117,C122-124 .01 uF disk cap "103" or "103M
1 C14 .022 uF monolithic cap '223'
6 C15,19,39,C118,C119,C121 .1 uF monolithic cap '104'
2 C21,C22 1 uF electrolytic cap
1 C20 3.3 uF electrolytic cap
2 C18,C23 10 uF electrolytic cap
1 C24 47 uF electrolytic cap