Paia 9720, Assembly And Using Manual

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8 9720 VCO 010321
Diodes
Like the Electrolytic Capacitors, diodes are polarized
and must be installed so that the lead on the banded
end of the part corresponds to the banded end of the
designator on the circuit board. Bend the leads so they
are at right angles to the body of the part and insert
them through the holes provided in the circuit board.
Diodes are also somewhat heat sensitive so the
soldering operation should be done as quickly as possible.
DESIGNATION TYPE
listed below: 1N4148 Silicon Diode
( ) D1 ( ) D2 ( ) D3 ( ) D4
( ) D5 ( ) D6 ( ) D7 ( ) D8
( ) D9 ( ) D10 ( ) D11 ( ) D12
( ) D13 ( ) D14 ( ) D15 ( ) D16
( ) D17 ( ) D18
Transistors
Install the transistors by inserting their three leads
through the holes provided for them in the circuit board.
Note that the transistors are polarized by the flat side
of the case. When the transistors are properly
installed this flat will align with the corresponding mark
on the circuit board legending.
Four of the transistors are supplied as pairs that have been
specially selected to have matching characteristics and will
be packed together. Keeping these pairs together is important
for optimum circuit performance.
Notice that two different types of transistors (2N3904 and 2N3906)
are used. The type will be written on the body of the part.
DESIGNATION TYPE
listed below: 2N3906 PNP Silicon Transistor
( ) Q2/Q3 ( ) Q8/Q9 matched pairs
( ) Q1 not matched
( ) Q4 not matched
listed below: 2N3904 NPN Si Transistors not matched
( ) Q5 ( ) Q6 ( ) Q7 ( ) Q10
The straight line of the pc
graphic symbol corresponds
to the flat face of the
transistor case.
Note flat
Note diode
polarity band