Tektronix TYPE L Instruction Manual page 18

chassis and remove the terminal strip. Screw
a #2-56 nut onto each bolt of the new strip,
positioning the nut so that the distance between
the bottom of the nut and the bottom of the
ceram ic strip equals the height at which you
wish to mount the strip above the chassis.
Secure the nuts to the bolts with a drop of
red lacquer. Insert the bolts through the holes
in the chassis where the original strip was
mounted, placing a #2 starwasher between each
nut and the chassis. Place a second set of #2
flatwashers on the protruding ends of the
bolts, and fasten them firm ly with another
set of #2-56 nuts. Place a drop of red lacquer
over each of the second set of nuts after
fastening.
Fig. 4-1. Two types of ceramic strip mountings.
A ceram ic terminal strip mounted with snap-
in plastic fittings is most easily removed by
unsoldering all connections, then using aplastic
o r hard rubber mallet to tap the mounting
clips out of the chassis.
by tapping on the ends of the clips protruding
through the reverse side of the chassis. When
a new strip is ordered, the mounting clips
are furnished with and are attached to the
strip. New spacers need not be ordered because
the original spacers can be used two o r three
tim es before they become too loose to hold
the clips securely.
When the damaged strip and clip assembly
have been removed, place the spacers fo r
the new strip assembly into the holes in the
4-2
This can be done
however, are standard electronic parts that
can generally be obtained locally in less time
Maintenance - Type L Plug-In
chassis. Using a plastic or hard rubber m allet,
tap the ceram ic strip lightly above the mounting
clips to drive the pins down through the spacers.
Be certain that the clips are driven down
to the spacers. Using a pair of diagonal cutters,
cut off the excess length of the mounting clips.
Soldering Precautions
In the production of Tektronix instruments,
a special silver-bearing
establish a bond to the ceram ic terminal strips.
This bond may be broken by the repeated use
o f ordinary tin-lead solder, or by the appli­
cation of too much heat.
ordinary solder w ill not break the bond however,
unless too much heat is applied.
If continued maintenance work is to be per­
form ed on Tektronix instruments, it is advisable
to have a stock of solder containing about
3% silver. This type of solder is often used
fo r work on etched-circuit boards and should
be readily available. It may also be purchased
directly from Tektronix in one pound rolls
(part number 251-514).
Because of the shape of the terminals on
the ceram ic terminal
iron should have a thin wedge-shaped tip.
This allows the heat to be applied directly
to the solder in the terminals and reduces
the amount of heat required. It is important
to use as little heat as it possible.
use force or twist the tip of the soldering iron
in the terminal slot as this may chip or break
the ceram ic strip. Apply only enough solder
to cover the wires adequately. Do not attempt
to fill the notches with solder.
When soldering to terminal pins mounted
in plastic, it is necessary to use some form
o f " heat sink" on the terminal between the
soldering iron and the plastic, to avoid damaging
the plastic. A pair of long-nosed pliers is
convenient for this purpose.
R E P L A C E M E N T P A R T S
Standard Parts
Replacement for all parts used in the Type L
Unit can be purchased directly from Tektronix
at current net prices. Many of the components,
solder is used to
Occasional use of
strips, the soldering
Do not
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