Simpson 260 - Resistor Replacement

МАЛДАИЈОМА МО
In the Model 270, it is not advisable to sub-
stitute if the original characteristics are to be
maintained.
After you replace either or both rectifiers,
test the accuracy of А.С. voltage indications.
If necessary, recalibrate the circuit by adjust-
ing rheostats R-28 and Е-31 as follows:
l. Set the function switch at A.C. and the range
switch at 250 V.
2% Connect the red test lead in the + jack and
the black test lead in the CCMMON - jack.
3. From the standard voltage source, apply 250
volts A.C. to the red and black test leads.
Adjust rheostat R-31 (which is next to the +
meter stud on the printed circuit board) so
the meter reads full scale. Turn power off.
4e Set: the range switch to 2.5 Ve Apply 2.5
volts A.C. to the red and black test leads.
Adjust rheostat R-28 (which is next to R-31)
so the meter reads full scale. Turn power
off,
If no standard voltage supply is available
for the above procedure, use this alternate method:
l. Set the function switch at A.C., and the range
switch at 2.5 Ve
2. Connect the red test lead in the + jack and
the black test lead in the COMMON - jack.
3. Connect the test leads to a fresh 1,5 volt
flashlight cell. Connect the red test lead
to the positive post of the battery and the
black test lead to the negative poste.
32
Form 2212 — РА S.A.