Tektronix 323, Instruction Manual

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Operating Instructions— Type 323
Infernal battery-powered operation should not be con­
tinued after the LOW BATT lamp starts flashing. The bat­
tery should immediately be put on charge at a FULL CHG
rate to avoid the possibility of individual cells becoming
reverse-charged. Operation can continue during recharge.
If internal battery-powered operation is inadvertently con­
tinued after the LOW BATT lamp starts flashing, eventually
the trace will disappear and the light will stop flashing;
damage to the battery NiCd cells may result.
WARNNG
The battery used in the Power Pack is capable of
delivering a large amount of energy in a short
time. Rings, watch bands, or other metallic items
which short-circuit the battery can rapidly become
hot enough to cause severe burns. Keeping the
Power Pack switch at EXT DC minimizes the num­
ber of points in the circuitry to which the battery
voltage is applied.
External DC-Powered Operation
The Oscilloscope can be powered by an external DC source
of between 6 and 16 volts. The external DC power source
must be connected to the EXT DC POWER connectors on
the right side of the Oscilloscope, and the Power Pack switch
placed at EXT DC. The external DC source will not charge
the internal battery.
CAUTION
Do not apply reverse polarity to the EXT DC
POWER connectors. It will blow the high voltage
fuse.
AC-Powered Operation
An AC source can be used to power the Oscilloscope when
the Power Pack switch is at either TRICKLE CHG or FULL
CHG. In addition, the battery charges at the indicated rate
whenever AC is applied, regardless of the status of the
Oscilloscope POWER switch. It may be noted that if the
Power Pack switch is left in EXT DC when AC is applied,
the infernal battery will charge at the full charge rate, even
though AC or internal battery-powered Oscilloscope opera­
tion is interrupted.
Either 115 or 230 V nominal AC power may be used, but
slip-on connectors at the Power Pack must be connected in
accordance with the voltage to be used. The infernal fuse
must also be changed whenver the AC voltage range is
changed. Spare fuses for 115 V and 230 V operation are
contained inside the Oscilloscope adjacent to the side con­
trol panel. The following procedure explains the Power
Pack removal, connection changes, and Power Pack replace­
ment.
Power Pack Removal. Disconnect all cables from the
Oscilloscope and place the Oscilloscope Power Pack switch
at EXT DC.
Remove the cover-securing screw from the back of the
case. See Fig. 2-2(A).
Grip the front edge of the Oscilloscope with one hand,
and the cover assembly with the other hand as shown in
Fig. 2-2(B). Pull the cover assembly off the chassis, main­
taining a firm grip on the front of the chassis.
Set the Oscilloscope chassis down on a flat surface. Dis­
connect the three interconnecting leads and release the
Power Pack securing clamp. See Fig. 2-2(C).
Move the Power Pack approximately V4 inch toward the
rear of the chassis to release the positioning lugs. Then
remove the Pack sideways from its mounting area. Use
caution to avoid striking transformer wires or the circuit
board against the Oscilloscope chassis.
1 1 5 /2 3 0 V Connection Changes. Fig. 2-2(C) illustrates
the location of the jumper wires and of the fuse. The two
possible circuit arrangements, accompanying fuse sizes and
the locations of spare fuses are indicated in Fig. 2-3. Re­
install the insulated tubing over the unused AC terminals.
Location o f fuse fo r 23 0 -V o p eratio n and spare fuses fo r
1 1 5-V AC line circuit and Power R egulator circuit.
(A ) Spare fuse location.
C D
C D
□ ° V r >
P
2 3 0 V
2 3 0 V
[ □
D — ©
□ 0 ^
E
f
e
r
IB ) 11 5-V connection (C) 23 0 -V connection
Fuse size — 0 .2 5 A Fuse size — 0 .1 2 5 A
Fig. 2 -3 . Connections fo r 115 V and 2 3 0 V AC operatio n.
Power Pack Replacement. Replace the Power Pack by
reversing the removal procedure, insuring that the wire color
code agrees with that written on the terminal mounting.
See Fig. 2-2(C). Avoid pinching of fingers at the front panel
when the Oscilloscope cover is replaced.
IMPORTANT
The Oscilloscope will not operate from the internal
battery or from an AC source if the Power Pack
switch is left in the EXT DC position. However, it
may be noted that if the switch is left in this posi­
tion and AC is applied, the battery will charge
at a full-charge rate.
Charging
Although the battery contained in the Type 323 Oscillo­
scope is charged before packaging, it should be recharged
for 16 hours at a FULL CHG rate when put into service.
® I
2-7