Vectronics VEC-1016K, Руководство пользователя

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When you look at a resistor, check its multiplier code first. Any resistor with a black
multiplier band falls between 10 and 99 ohms in value. Brown designates a value
between 100 and 999 ohms. Red indicates a value from 1000 to 9999 ohms, which is
also expressed as 1.0K to 9.9K. An orange multiplier band designates 10K to 99K, etc.
To inventory resistors, first separate them into groups by multiplier band (make a pile of
10s, 100s, Ks, 10Ks, etc). Next, sort each group by specific value (1K, 2.2K, 4.7K, etc.).
This procedure makes the inventory easier, and also makes locating specific parts more
convenient later on during construction. Some builders find it especially helpful to
arrange resistors in ascending order of value along a strip of double-sided tape.
Some VEC kits may contain molded chokes which appear, at first glance, similar to
resistors in both shape and band marking. However, a closer look will enable you to
differentiate between the two. Chokes are generally larger in diameter and fatter at the
ends than resistors. When doing your inventory, separate out any chokes and consult the
parts list for specific color-code information.
Reading Capacitors: Unlike resistors, capacitors no longer use a color code for value
identification. Instead, the value, or a 3-number code, is printed on the body.
Multilayer
271
(270 pF)
Ceramic Discs
|
|
1uF
+
-
104
Electrolytic
10 pF = 100
100 pF = 101
1000 pF = 102
.001 uF = 102*
.01 uF = 103
.1 uF = 104
Value Code
102
(.001 uF) (.1 uF)
As with resistors, it's helpful to sort capacitors by type, and then to arrange them in
ascending order of value. Small-value capacitors are characterized in pF (or pico-Farads),
while larger values are labeled in uF (or micro-Farads). The transition from pF to uF
occurs at 1000 pF (or .001 uF)*. Today, most monolithic and disc-ceramic capacitors are
marked with a three-number code. The first two digits indicate a numerical value, while
the last digit indicates a multiplier (same as resistors).
Electrolytic capacitors are always marked in uF. Electrolytics are polarized devices and
must be oriented correctly during installation. If you become confused by markings on
the case, remember the uncut negative lead is slightly shorter than the positive lead.
Diodes: Diodes are also polarized devices that must be installed correctly. Always look
for the banded--or cathode--end when installing, and follow instructions carefully.