Elecraft KX1 Manual - Manual (Page 10)

E
LECRAFT 9
Identifying Resistor Packs
Resistor packs combine a number of resistors in one component with
multiple leads. They may be in-line packages with 6 or 10 leads in a
row or they may be in 16-pin dual in-line pin (DIP) packages similar
to many integrated circuits.
Like integrated circuits, pin 1 of each component is identified by a dot
near it. Some resistor packs are symmetrical. That is, they can be
installed either way. However, some are not. ALWAYS follow the
instructions and orient the resistor pack exactly described in the
procedure.
The value of the resistor pack is indicated in the last three digits shown
on the package. The numbering scheme is similar to capacitors. The
first two digits indicate the first and second most significant digits and
the third digit is a multiplier. For example, “...391” indicates 390 ohms
and “...104” indicates 100,000 ohms (100K).
Identifying Capacitors
Capacitors are identified by their value and the spacing of their leads.
Small-value fixed capacitors are usually marked with one, two, or
three digits and no decimal point. If one or two digits are used, that is
the value in picofarads (pF). If there are three digits, the third digit is a
multiplier. For example, a capacitor marked "151" would be 150 pF
(15 with a multiplier of 10
1 ). Similarly, "330" would be 33 pF, and
"102" would be 1000 pF (or .001 µF). Exceptions are described
specifically in the text and parts list.
Fixed capacitors with values of 1000 pF or higher often use a decimal
point in the value, such as .001, .047, or 2.2. This is the value in
microfarads (µF). (1 µF is equal to 1,000,000 pF.)
The lead spacing is noted in the Parts Lists for most capacitors. If two
different types of capacitors have the same lead spacing will indicate
which one to use. When lead spacing is important, both the value and
the lead spacing is shown in the assembly procedure. For example,
“LS 0.1” means that the lead spacing is 0.1 inch (2.5 mm).
Identifying Toroid Cores
Several toroidal inductors are used in the KX1. It is important to use
the correct type of core. This can be determined from the color and
size. Two types of cores are used in the KX1: Iron powder cores and
ferrite cores. If you mix them up, your KX1 will not operate properly.
The iron powder cores used are type T37-6. The T identifies an iron-
powder core. The number following the T specifies the outside
diameter in hundredths of an inch, in this case 0.37 inches (9.4 mm).
The suffix (-6) refers to a specific mix of iron powder. You cannot tell
what mix of iron power is used by looking at the core, so they are
painted with specific colors. The -6 cores are painted yellow.
Ferrite cores are indicated in the parts list by the letters FT in the part
number. The KX1 uses FT37-6 cores. Like the iron powder cores, the
37 refers to the outside diameter. The -46 identifies the type of ferrite
used. These cores are not painted. They are dark grey.