Tektronix TYPE CA Instruction Manual page 14

strips. The notches in these strips are lined
with a silver alloy. Repeated use of excessive
heat, or use of ordinary tin-lead solder will
break down the silver-to-ceramic bond. Occa ­
sional use of tin-lead solder will not break the
bond if excessive heat is not applied.
If you are responsible for the maintenance of
a large number of Tektronix instruments, or if
you contemplate frequent parts changes, we
recommend that you keep on hand a stock of
solder containing about 3% silver. This type
of solder is used frequently in printed circuitry
and should be readily available from radio ­
supply houses. If you prefer, you can order
directly from Tektronix in one-pound rolls.
Order by Tektronix part number 251-514.
Because of the shape of the terminals on
the ceramic strips it is advisable to use a
wedge-shaped tip on your soldering iron when
you are installing or removing parts from
the strips. Fig. 4-1 will show you the correct
shape for the tip of the soldering iron. Be
sure and file smooth all surfaces of the iron
which will be tinned. This prevents solder
from building up on rough spots where it
will quickly oxidize.
Fig. 4-1. oldering iron tip properly shaped and tinned.
When removing or replacing components
mounted on the ceramic strips you will find
that satisfactory results are obtained if you
proceed in the manner outlined below.
1. Use a soldering
rating.
2. Prepare the tip of the iron as shown in
Fig. 4-1.
4-2
http://manoman.sqhill.com
iron of about 75-watt
Maintenance - Type CA
3. Tin only the first 1/16 to 1/8 inch of the
tip. For soldering to ceramic terminal
strips tin the iron with solder containing
about 3% silver.
4. Apply only one corner of the tip to the
Fig. 4-2. Correct method of applying heat in soldering to a ceramic
strip.
5. Apply only enough heat to make the solder
flow freely.
6. Do not attempt to fill the notch on the strip
with solder; instead, apply
solder to cover the wires adequately, and
to form a slight fillet on the wire as shown
in Fig. 4-3.
F LLET
Fig. 4-3. A slight fillet of solder is formed around the wire when
heat is applied correctly.
In soldering to metal terminals (for
pins on a tube socket) a slightly different
nique should be employed. Prepare
as outlined above, but tin with
lead solder. Apply the iron to the
soldered as shown in Fig. 4-4. Use
heat to allow the solder to flow
the wire so that a slight fillet will
as shown in Fig. 4-3.
only enough
SOLDER CONNECT ON
example,
tech ­
the iron
ordinary tin ­
part to be
only enough
freely along
be formed
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