Tektronix 570, Manual

Page: 38 / 134

Fig.
4-1.
Soldering iron tip properly
sbaped and
tinned.
are installing or removing parts from the
strips.
Fig. 4 - 1 will show you the correct
s hape for the tip of the soldering iron. Be
sure to file smooth a l l surfaces of the iron
which will be tinned. This prevents solder
from building up on rough spots where it will
quickly oxidize.
When removing or replacing components
mounted on the cer�mic strips you will find
that s atisfactory results are obtained if you
proceed in the manner outlined below.
1 . Use a soldering iron of about 7 5 - watt
rating.
2 . Prepare the tip of the iron as shown in
F i g . 4 - 1 .
3 . Tin only the first 1 / 16 to 1 /8 inch of
the tip. For soldering to ceramic terminal
s trips tin the iron with solder containing about
3% silver.
F i g .
4-2.
Correct method of applying
heat in
soldering t o
a ceramic
s t rip.
4. Apply one corner of the tip
to
the notch
where you wish to solder (see Fig. 4 - 2 ) .
5 . Apply only enough heat t o make the solder
flow freely.
6.
Do
not attempt to fill the notch on the strip
with solder; instead, apply only enough solder
to cover the wires adequately . and to form a
s light fillet on the wire as shown in Figure
4 - 3 .
Fig.
4-3. A
slight fillet o f solder
i s
formed around t h e wire when
h
e
a
t
is
applied correctly.
In soldering a metal terminal (for example .
pins on a tube socket) a slightly different
technique should be employed. Prepare the
iron as outlined above . but tin with ordinary
tin-lead solder. Apply the iron to the part to
be soldered as shown in Fig. 4 - 4 . Use only
enough heat to allow the solder to flow freely
along the wire so that a slight fillet will be
formed as shown in Fig. 4 - 4 .
Fig.
4 - 4 .
Soldering to a terminal. Note the sl
i
g
h
t fillet of solder - ­
exaggerated for clar!ty- -formed
around the wire.
4 - 2
Maintenance - Type 570
AA