Heathkit SB-401 Assembly Manual page 99

( ) Slide the 1/4" x 3-7/8" shaft through front
panel bushing FD, and into the shaft coupling
on variable capacitor TA. The shaft should
extend 5/16" from the front of the bushing
at FD. Tighten the front setscrew in the shaft
coupling. If binding of the drive shaft occurs,
readjust bushing FD. Be sure the setscrews
in the shaft coupling are tightened securely.
( ) Start two 6-32 x 3/16" setscrews in the
threaded holes of a 1/4" shaft coupling.
( ) Slide the shaft coupling as far as possible
onto the shaft of variable capacitor TA,
and tighten the rear setscrew.
( ) Position this pulley assembly even with the
rear end of the tubular shaft and tighten
the setscrew.
Detail 5-6C
( ) Slide the 17/64" x 8-1/4" tubular control
shaft over the 3/16" dial shaft and into the
pulley assembly (#100-458).
( ) Lightly grease the 3/16" dial shaft with
silicone grease.
( ) Center the bushing at FA as close as possi-
ble with the 3/16" dial shaft, and tighten the
bushing.
( ) Slide the 3/16" dial shaft
into this shaft
coupling until 7/16" of the shaft extends
from the front of bushing F A. Tighten the
setscrew in the shaft coupling on variable
capacitor TD.
17/64" TUBULAR
SHAFT
( ) Loosen the front setscrew in the shaft
coupling on variable capacitor TD.
# 100-458
( ) Place the 3/16" x 9-3/8" dial shaft through
front panel bushing FA, through the dial
pulley assembly (#100-458), and through the
hole at TG.
Refer to Detail 5-6C for the following steps.
( ) Start an 8-32 x 1/4" setscrew into the
threaded hole of the dial pulley assembly
(#100-458).
7/16"..._..
( ) Connect the white-violet wire com.ing from
grommet
HA
to lug
1
of terminal strip TP
(S-2).
8-32x1/4"
SETSCREW
( ) Connect the violet wire coming from grom-
met HA to lug 3 of terminal strip TP (8-3).
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