Two different sizes of screws and hex nuts are used. The 6-32
screws are thicker than the 4-40 screws.
- Use four 4-40 screws and hex nuts to mount the solderless
breadboard inside the case as shown in Fig. 4. The rows and
columns of holes in the breadboard are numbered. Align the
breadboard so that column number 1 is closest to the rigid side
of the case. Insert the screws through the bottom side of the
case. Tighten the screws and hex nuts with a screw driver and
pliers.
- Use a file to remove 1 mm from the end of an angle bracket.
Mark the filed end with a colored marker or pencil.
- Place the angle bracket in front of the breadboard as shown in
Fig. 4. Adjust the bracket until it is 2.25 cm from the inside of
the rigid side of the case. The holes in the bracket will then be
aligned with columns 2 and 3 of the breadboard.
- With the bracket pushed flush against the breadboard, mark a
drill guide in the bottom of the VHS case at the center of the
hole in the bracket.
- Use a 5/32-inch bit or its metric equivalent to drill a hole
at the drill guide you just marked. Hold the case firmly while
drilling. Carefully use a hobby knife to remove any plastic
attached to the edge of the hole.
- Insert a 6-32 screw through the back side of the case and the
hole in the unfiled end of the angle bracket. Place a 6-32 hex
nut over the screw.
- Make sure the filed end of the angle bracket faces up. Then
press the bracket flush against the breadboard and tighten the
screw and nut with a screw driver and pliers.
- Refer to Fig. 2 and measure the exact distance of the center
of the upper hole in the angle bracket from the inside of the
rigid side of the case (2.25 mm in the prototype) and the bottom
of the case (1.7 cm). Then mark a drill guide in the front of the
case that exactly matches these dimensions.
- Double check the drill guide you just marked to make sure it
is centered directly over the hole in the angle bracket installed
inside the case. Then use a 9/32-inch bit to drill a hole at the
drill guide. If you don't have this drill bit, drill a smaller
hole and carefully enlarge it with a reamer or hobby knife.
- Install the two 9-volt battery clips on the inside of the
flexible side of the case using 6-32 screws and hex nuts at the
locations shown in Fig. 4. Be sure to insert the screws through
the battery holders and then through the inside of the flexible
side of the case. Tighten the screws and hex nuts with a screw
driver and pliers.
- Install two angle brackets on the outside of the case using
6-32 screws and hex nuts. Orient the brackets as shown in Fig. 3.
Be sure the edges of these brackets are flush with the shoulder
that protrudes along the bottom edge of the case as shown in Fig. 3. (If one or both brackets are not flush, enlarge the hole
slightly so the bracket can be pushed against the shoulder.) Make
sure the lid of the VHS case closes properly. Then tighten the
screws and hex nuts with a screw driver and pliers.
- Remove the hex nuts and lock washers from the two binding
posts. Insert the threaded ends of each binding post into the
holes shown in Fig. 4. Install the black binding post nearest the
end of the case. Replace the locking washers and hex nuts and
tighten with pliers.
- Place the solderless breadboard over its mounting holes so
that the row of holes designated 1 is next to the rigid side of
the case. Insert 4 4-40 screws through the back of the case and
hold them in place with 4-40 hex nuts. Tighten the screws and hex
nuts with a screw driver and pliers.
- Stop for a moment to review what you have done so far. Are
the external angle brackets flush with the shoulder that extends
along the bottom of the case? Are all the hex nuts tightened?
Does the case close properly?
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