Tektronix 323, Инструкция по эксплуатации

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Maintenance— Type 323
POWER REGULATOR TROUBLESHOOTING CHART
Initial setup: VOLTS/DIV at 5 DIV CAL; POSITION controls "in" and centered; TRIG­
GER at AUTO; TIME/DIV at 1 mS; Trig/Horiz Coupling switch at INT—AC; 115 V, 60
Hz AC power applied; POWER— ON; INTENSITY control at maximuum brightness setting.
The following observations were made with the indicated transistor removed from the
circuit to simulate its being open. The chart need not be restricted to the transistors them­
selves, but can be used as a basis for tracing symptoms to areas of the Power Regulator
circuit which are associated with indicated transistors. Circuit response may vary slightly
between instruments.
Transistor
Removed
Reaction o f Power Supplies
(N e ar normal unless
indicated otherwise)
Comments
High Low
0 or
near 0
Q515 all
DC on Q525-C
Q518 all
DC on Q525-C
Q525 all
DC on Q525-C
Q529
all
40 V P-P pulses on Q525-C
Q555 + 5 , - 5 Glow visible in CRT
Q557
+ 5 , - 5
Display visible; INTENSITY
affects triggering and causes
"blooming".
Q558 + 5 , - 5
Glow visible in CRT
Q562 - 5
Normal amplitude display
visible; INTENSITY affects
triggering and positioning;
Top and bottom of square
wave distorts when display
is not centered vertically.
Q567 - 5
Q569 all - 5 All voltages (except —5)
approximately 40% of nor­
mal value; 35 V P-P pulses
on Q525-C.
Fig. 4 -4 . Power R egulator troublesh ootin g chart.
A solder removing device such as an EDSYN SOLDAPULLT,
Tektronix Part No. 003-0428-00, is extremely useful in remov­
ing solder from circuit boards, expediting component remov­
al and replacement.
Other soldering aids should be made or purchased to
suit specific needs.
General Soldering Techniques. Keep the soldering iron
well tinned and wiped clean. To avoid excessive heating of
the general area around the connection, the iron should be
completely heated before being applied. When removing
components, apply heat only long enough to allow the part
to be removed easily. (Applying a small amount of solder
between the tip and the joint will usually aid in heat transfer
on difficult connections. This will decrease heating of the
general area.) Use the extreme tip of needle-nosed pliers
to avoid drawing off too much heat. When connecting com­
ponents, heat the solder sufficiently to allow free flow.
Apply the solder to the wire being joined, not to the solder­
ing iron. This will insure proper bonding. (Applying a small
amount of solder between the iron and the wire will again
aid in initial heat transfer. Once solder flows between the
tip and the wire, the solder should be applied to the opposite
side of the wire to complete the process.) Do not use more
solder than is necessary to make a neat and effective bond.
Use heat sinks between the body of components and the
joint being soldered whenever small components and/or
short leads are involved. After soldering has been completed,
clip off excess wire, deflecting wire ends with a gloved
finger or other device to avoid damage to fingers, eyes,
or circuit components. Remove clipped leads from the chassis.
Clean the newly soldered area with a cotton-tipped swab
and flux remover solvent.
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