Time Symmetry Cannot Be Adjusted To Within Specifications; Trigger, Gating And Trigger Baseline Problems - Wavetek 193 Instruction Manual

6-7
6.3.12 Trigger, Gating and Trigger Baseline
Problems
Improperly set controls:
1. MODE incorrectly set to CONT.
2. FUNCTION incorrectly set to DC.
3. DC OFFSET overdriving output amplifier.
nominal with less than 100 mVp-pac ripple. If not,
refer to paragraph 6.4.1.
2. If the problem occurs in one of the four lowest fre-
quency ranges (.1, 1, 10, 100), but the remaining
ranges are normal, refer to paragraph 6.4.9.
3. If the frequency accuracy is out of specitlcatlon
on FREO MULT settings 1M and 10M, refer to
paragraph 6.4.3.
4. If the frequency is out of specification, but only on
one range, check the range capacitor for that
range.
5. If the problem occurs on the 1K, 10K, or 100K
range, check the range capacitor.
6. On the 1K range and frequency dial set at 2.0,
check for 3.8V across R86 and R97. As the FRE-
O/STARTFREOdial is rotated, this voltage should
linearly track the dial settings within ± 3% of full
scale. If not, refer to paragraph 6.4.2.
7. If none of the above conditions apply, refer to
figure 6-7.
Functional block isolation:
1. Verify power supply voltages are within ± 5% of
6.3.11 Frequency Accuracy and FREQ/START
FREQ Dial Response Problems
Improperly set controls:
1. SYM button depressed.
2. External signal connected to VCG in BNC.
3. VERNIER not in FREOCAL position.
Functional block isolation:
1. Verify power supply voltages are within ± 5% of
nominal, with less than 100 mVp-p of ac ripple. If
not, refer to paragraph 6.4.1.
2. If symmetry is out of specification in one of the
four lowest ranges (.1, 1, 10, 100), but the remain-
ing ranges are normal, refer to paragraph 6.4.9.
3. If symmetry is out of specification on FREOMULT
settings 1M or 10M only, refer to paragraph 6.4.3.
4.
If the voltages across R86 and R97 are not equal
(typically 3.8V, Freq Dial: 2.0 Freq Mult: 100K or
less), refer to paragraph 6.4.2
6.3.10 Time Symmetry Cannot Be Adjusted To
Within Specifications
Improperly set controls:
1. SYM button depressed.
Figure 6·6. Low Frequency Square Wave Troubleshooting
REFER TO
PREAMPLIFIER GUIDE
6.4.14
REFER TO SQUARE
SHAPER GUIDE
6.4.12
YES
CHECK OUTPUT
ATTENUATOR
REFER TO OUTPUT
AMPLIFIER GUIDE
6.4.15