Asa Brush Adjustment; Diaphragm Accuracy Check - Canon A-1 Repair Manual

4. Lube Spring (CSl-5l8l-000) with LT-SH •
. 2,22 ASA Brush Adjustment
1. This adjustment is made with the top cover in place :
The SV Check Bit Tool -15 is used.
Eccentric Screw
SV Check Bit Tool
Fig. 2-30
2. Place the ohmmeter leads into holes Pl and P2. The
ohmmeter should be set to a low range.
(An
analog
ohmmeter is easier to read than a di~ital meter).
3. Holding the leads against the pattern under the bit
and moving the tool as far as possible in the A and
B directions, the meter should indicate an open
circuit at both ends and continuity . in the center.
4. Adjust with the eccentric · screw so the OFF
(~),
ON (00), OFF
(~)
condition is met.
Note: This adjustment affects exposure accuracy.
Readjust if the top cover or the ASA Contact
is changed.
Refer to the tools instructions for the SV
Check Bit-1S.
2.23 Diaphragm Accuracy Check
42
This adjustment checks the accuracy of the programmed
control of the lens diaphragm in the aperture priority
mode. A special tool lens is used to perform this
adjustment where it is available, but it can be per-
formed with an oridnary FD 50 rom 1:1.4 with a well
calibrated diaphragm.
Note: When using an ordinary lens, the shutter speed