Tektronix 516 series, Инструкция по эксплуатации

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Maintenance — Type 5 1 6
Fig. J.1 Removing the oscilloscope li d * panels.
the crt. Removo tho crt by pushing forward on the tube
base and then pulling the tube straight out through the front
panel (see Fig. 5-2).
When the new crt is in place, the leads con be properly
connected to tho neck of the tube by following the color
code information provided on the tube shield. After replace­
ment of the crt, it moy be necessary to calibrate certain
portions of the oscilloscope. Special attention should be
given to calibration of tho sweep timing and the Vertical
Amplifier gain.
Replacement of Switches
Methods for removal of defective switches ore, for the
most part, obvious and only a normal amount of core is re­
quired. Single wafers are normally not replaced on the
switches used in the instrument, If one wofer is defective,
the entire switch should be replaced. Switches can be order­
ed from Tektronix either wired or unwired, os desired
Tube Replacement
Care should be taken both in preventive and corrective
maintenance that tubes are not replaced unless they ore ac­
tually causing trouble. Often during routine maintenance
it will be necessary to remove tubes from their sockets. It is
important that these tubes be returned to their original sock­
ets unless they are actually defective Unnecessary replace­
ment or switching of tubes will often necessitate calibration
of the instrument. If tubes do require replacement, it is rec­
ommended that they be replaced by previously checked,
high-quality tubes
Soldering Precautions
In the production of Tektronix instruments, a special silver­
bearing solder is used to establish o bond to the ceramic
Fig 3 -2 . (( m o v in g th * co lh o d e -ro y Ivb#
terminal strips This bond con be broken by repeated use
of ordinary tin-lead solder, or by the application of too
much heat. However, occasional use of ordinary solder will
not break the bond if too much heat is not applied.
It is advisable to have a stock of solder containing about
3% silver if you frequently perform work on Tektronix
instruments. This type of solder is used frequently in printed
circuitry and should be readily available. It may also be
purchased directly from Tektronix in one-pound rolls (order
by Tektronix Part Number 251-05M-00).
Because of the shape of the terminals on the ceramic
terminal strips, it is advisable to use a wedge-shaped tip on
your soldering iron when installing or removing parts from
the strips. A wedge-shaped lip allows you to apply heat
directly to the solder in the terminals and reduces tho amount
of heat required. It is important to use as little heat as pos­
sible.
Ceramic Terminal Strips
Damaged ceramic terminal strips are most easily removed
by unsoldering all connections, thon using a plastic or hard
Ceramic Strip Yoke
Chassis Spacer Yoke Pin
5 - 2
Fig. 5 -3 . In s ta lla t io n o f c o ra m k te rm in a l s trip *.