Tektronix TYPE 109, Инструкция по эксплуатации

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Calibration— Type 109
C A U TIO N
W hen using this tester in step 4 of the calibration
procedure, do not insert the b an an a plugs all the
w a y without checking whether or not the plugs
are too large Most b an an a plugs can be safely
inserted o nly part w a y without d a m ag in g the GR
connectors.
(7) One VOM with a sensitivity of at least 5,000 fi/volt.
(8) An autotransformer with output voltage variable between
105 and 125 volts (or 210 and 250 volts if Type 109 is
wired to operate in this range). Minimum rating of 0.070
KVA.
(9) An accurate ac voltmeter capable of reading voltages
from 105 to 125 volts (or from 210 to 250 volts if the
Type 109 is wired for this operating range).
(10) One 12" jumper lead with insulted alligator clips on
each end.
(11) One screwdriver.
Preliminary Procedure
Visually check the Type 109 and then preset the front-
panel controls to these positions:
VO LTAG E RAN GE 50
POWER OFF
Using the VO M , check the resistance to ground of each
power supply at the test points listed in Table 6-1. Refer
to Fig. 6-3 which shows the location of these test points.
♦ P o la rity d e p e n d s on se ttin g o f PU LSE P O L A R IT Y sw itc h . Be
sure V O L T A G E R A N G E sw itch is set to 5 0 fo r re sista n ce
f i n d / o r 1 O O- vft lt r e n d i n a c
F ig . 6 - 3 . Left sid e v ie w , fro n t p o rtio n , sh o w in g the lo c a tio n of
the test p o in ts.
After completing the resistance checks, disconnect the
ohmmeter.
TABLE 6-1
Power Supply
Test Points*
Ohmmeter
Range
Approx.
Resistance
Readings**
PULSE
POLARITY
Switch Setting
± 1 0 0 V XI k 7k, 18k
+
± 1 00V X lk
7k, 18k
—
+ 17V
R10 18Q, 30Q
+ or —
* Fig. 6-3 shows the physical locations of these test points.
**Reverse the ohmmeter leads to obtain both readings.
CALIBRATION PROCEDURE
Introduction
The equipment used in this calibration procedure is the
same as that specifically called out in the “ Equipment
Required" list. The front-panel control settings of this equip­
ment are given where necessary for more detailed informa­
tion. Corresponding control settings should be used if you
are using substitute equipment. In addition, the following
procedure is based on a Type 109 which was wired for
117-volt nominal operation and operated on a line fre­
quency of 60 cps. If your Type 109 is wired for 234-volt
operation and you are operating it on a line frequency
other than 60 cps, allow for such differences when you
are using this procedure.
1. 100-Volt Power Supply Adjustment
a. Connect the autotransformer to a nominal 117-volt
source (or 234-volt source if the Type 109 is wired
for this nominal operating voltage).
b. Connect the Type 109 and ac voltmeter to the output
of the autotransformer.
c. Set the POWER switch to ON and adjust the auto­
transformer for an output of 117 volts (or other volt­
age for which the instrument is wired).
d. Set the PULSE POLARITY switch to + .
e. Connect the VOM to the ± 1 0 0 V test point (see Fig.
6-3).
f. Adjust the 100 V SET control (see Fig. 6-4) to obtain
a reading of exactly 100 volts.
g. Set the PULSE POLARITY switch to — and check for
a reading of 100 volts.
®
6-2