4
PR-40B PC Board Assembly
( )
Attach all of the resistors to the board excluding resistor R6. As with
all other components unless noted, use the parts list and component
layout drawing to locate each part and install from the "TOP" side of
the board bending the leads along the "BOTTOM" side of the board and
trimming so that 1/16" to 1/8" of wire remains. Solder.
( )
Install all of the capacitors on the board excluding electrolytic
capacitor C4. Be sure to orient the electrolytic capacitors correctly.
The polarity is indicated on the component layout drawing. Note the two
set of holes for C3 to accommodate two different size capacitors - use
the correct set depending on your capacitor. Solder.
( )
Install transistor Q1 on the PC board. The transistor must be turned to
match the outline on the component layout drawing. Solder.
( )
Install transistor Q2 on the PC board. The transistor must be oriented
so that its flat side is against the circuit board and should be
secured with a #4-40 X 1/4" screw.
( )
Install all of the diodes on the PC board making sure to orient each as
shown in the component layout drawing. Solder.
( )
Install all of the male PC type pins in female connector shells J1 and
J2 from the numbered side of the connector. Then install each connector
in its proper location oriented as shown in the component layout
drawing. Solder.
( )
Now that all of the components have been installed on the board, double
check to make sure all have been installed correctly in their proper
location.
( )
Check very carefully to make sure that all connections have been
soldered. It is very easy to miss some connections when soldering which
can really cause some hard to find problems later during checkout. Also
look for solder "bridges" and "cold" solder joints which are another
common problem.
This completes the assembly of the PR-40B circuit board.
Chassis Assembly
( )
Some of the print mechanisms we are supplying have two mounting holes
on the bottom while others have three. Install the appropriate number
of mounting screws thru the proper holes on the chassis by running a
number 6 - 32 X 1/2" screw thru the chassis from the inside followed by
a lockwasher and #6 - 32 nut. The printer mechanism itself will be
attached to these screws at a later time.
( )
Snap the large plastic bushing into the chassis from the outside of the
chassis.
( )
Attach fuseholder F1 to the chassis using a #6 - 32 X 3/8" screw,
lockwasher and nut. Orient the fuseholder as shown in the wiring
diagrams.
( )
Scrape away the anodizing around the mounting hole for TS-1 on the
inside of the PR-40 chassis. Scraping away the anodizing insures
electrical contact between the terminal strip and the chassis. Attach
lug strip TS-1 to the chassis using a #6 - 32 X 1/4" screw, lockwashers
and nut. Sandwich one lockwasher between the terminal strip and the
chassis. Orient the lug strip as shown in the wiring diagram.