Avo Brush Stopper Position (F/S.6 Maximum Aperture Position); Maximum Aperture Signal Pin Adjustment (Front Panel Only) - Canon A-1 Repair Manual

2.7 AVO Brush Stopper Position (f/S . 6 maximum aperture
position)
1. Position the AVO brush against its stopper (Fig. 2-9 ,
Detail B).
2. The contact part of the brush should be at P2 and the
other contact points should form line PS-PS'.
Adjustment: Bend the stopper striker (P3) portion
of the brush.
Note: Check that the finder information flash when an
f / S.6 lens is mounted and the brightness is below
the f/S.6 level.
2.8 Maximum Aperture Signal Pin Adjustment
(Front Panel Only)
30
Precautions: Adjustment of the pin has a direct effect
on the viewfinder display. It must be
adjusted correctly .
1.
If the pin is to be adjusted with this
procedure the flange focal distance (FFD)
should be adjusted before the front panel is
removed.
Two ohmmeters are necessary for
both be set on low OHM scales.
of meter A on
"fll
and the minus
this test. They should
Place the plus (+) lead
(-) on "a" (Fig. 2-9).
2. Place the + lead of meter B on "g" and the - lead on
"all (also Fig .. 2 - 9) .
3. Using a depth gage, slowly depress the maximum ape r ture
correction pin.
4. As the dep t h gage is depressed, meter A will show a
closed circu it and mete r B will show an open. At a
certain poi nt meter
A will
swing back toward ~ and B
will still be at
~
Slightly farther down, B will
swing toward O.
5. At the point where both meters are ' at ~ , the pin should
be 7.59 ±O.03mm below the mount surface.
(This point where both meters are at
~
is marked P4
on detail C of 2-9).