Canon A-1 Repair Manual page 152

86
3) Adjust the variable resistor until the oscillator
is with the frequency limits. Remove the variable
and measure it. Install a fixed resistor with a
resistance as near as possible to the resistance
of the variable.
OSC IC
ROle
CPU IC
Fig.
4-4
4) Recheck the frequency with the new resistor
installed.
3. RISET Check and Adjustment
This adjustment adjust the constant current supply
for magnets Kgl and Kg3 to 8 rnA.
1) Remove the black lead from the 2nd curtain magnet
(Kg3) and install a milliammeter in the line.
2) Release the shutter at bulb "B" -and read the
ammeter. The
cu rren~
should be 8
rnA
± lOt.
3) If the current is not within the limit, replace
the RISET resistor, which is normally about
4.5 KO, with one which will bring the current
into the limits. (A lower resistance resistor will
increase the current).