Maintenance— Type 1A1
for Tektronix, Inc. in accordance with our specifications.
These special parts are indicated in the Part List by an aster
isk preceding the part number. Most of the mechanical
parts used in this instrument have been manufactured by
Tektronix, Inc. Order all special parts directly from your
your Tektronix Field Office or representative.
Ordering Parts.
When ordering replacement parts from
Tektronix, include the following information:
1. Type 1A1 plug-in unit and serial number of the unit.
2. A description of the part (if electrical, include circuit
number).
3. Tektronix Part Number.
Soldering Techniques
Replacing Components on the Circuit Cards.'
Use ordin
ary electronic grade 60/40 solder and a 35- to 40-watt
pencil soldering iron with a y8-inch wide chisel tip. The tip
of the iron should be clean and properly tinned for rapid
heat transfer to a soldered connection. Use of a higher
wattage soldering iron increases the danger of ruining the
bond between the etched wiring and base material by char
ring the glass epoxy laminate. Component replacement
technique is as follows-.
1. To remove a defective component, cut the leads near
the body. This frees the leads for individual unsoldering.
2. Grip the lead with needle-nose pliers. Apply the tin
ned tip of the soldering iron to the lead between the pliers
and the solder joint; then pull gently.
3.. When the solder first begins to melt, the lead will
come out, leaving a clean hole. If the hole is not clean,
use the soldering iron and a toothpick or a piece of enamel
wire to open the terminal hole. Do not attempt to drill the
solder out since the plating inside the hole might be de
stroyed.
4. Clean the leads on the new component and bend them
to the correct shape. Carefully insert the leads into the holes
from which the defective component was removed.
5. Hold the leads of diodes .with tweezers or needle-nose
pliers to form a heat sink. Apply the iron for a short time
at each connection on the side of the board opposite the com
ponent to properly seat the component.
6
. Apply the iron and a little solder to the connections
to finish the solder joint.
7. Clean the flux from the solder joint with a flux-remover
solvent to maintain good environmental characteristics and
appearance.
CAUTION
The etched w ire (on the Channel 1 and Channel
2
input circuit board) that encircles the gate te r
minal o f Q 122 (o r Q 222) must never be soldered
to the gate terminal o f the FET.
'A card is essentially a circuit board that can be plugged into a
socket; the socket is used to make circuit connections to the card.
A circuit board, on the other hand, is fastened with screws to a
permanent mount; connections to a circuit board are made by pin
connectors a n d /o r soldered leads to the board.
Soldering to Metal Terminals.
When soldering to metal
terminals (e.g., switch terminals, potentiometers, etc), ordin
ary 60/40 solder can be used. The soldering iron should
have a 40- to 75-watt rating with a Vs-inch wide channel
shaped tip.
Observe the following precautions when soldering to
metal terminals.
1. Apply only enough heat to make the solder flow freely.
2. Apply only enough solder to form a solid connection.
Excess solder may impair the function of the part.
3. If a wire extends beyond the solder point, clip off the
excess.
4. Clean the flux from the solder joint as previously de
scribed.
Removing And Installing Circuit Cards
The circuit cards are the plug-in type and can be re
moved easily as follows:
1.
Unplug the ground lead and the leads which individ
ually plug into the card.
To remove the Channel 1 and Channel 2 -card, move the
spring clip out of the notch in the side of the card to per
mit removal of the card. To remove the Output Amplifier
card, remove the securing rod by removing the knob first.
3. Unplug the card and lift it out.
4. To install the card, plug it into the connector. Plug
the leads into the card. For the Channel 1 and 2 card, check
that the spring clip drops into the notch; for the Output
Amplifier card, check that the securing rod is properly in
stalled.
Removing And Installing The Input Circuit
Boards
The Channel 1 and Channel 2 Input Circuit boards can be
removed from the plug-in unit using the procedures given
here and referring to the illustrations of the boards provided
later in this section.
1. Remove the quick disconnects by the two transistors
in the plastic cover located on the amplifier card.
2. Unsolder the three leads on the upper side of the in
put circuit board.
3. Unscrew the two hold-down screws that hold the board
in place. Note the sequence of washers and spacer on the
hold-down screws.
4. Grasp the board and tip the outer edge upward, ex
posing the connections on the underside.
5. Remove the quick disconnects on the underside of the
board.
6
. Lift the board from the plug-in unit.
7. To install the board make the connections to the under
side of the board first. Mount the board in place and secure
if with the hold-down screws. Resolder the connections on
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