5-18.
PULSE ADJUSTMENTS (Cont’d)
NOTE
The following adjustments are required if any of the following four
assemblies have been replaced or if any of the controls listed after each
assembly have been adjusted or replaced.
All High Band Detector (Bands 1
-
4)
A21 Pulse Modulator Assembly, A21R45 (ON DELAY-INT), A21R47 (OFF
DELAY)
A25 ALC Detector Assembly, A25R58 (BAL)
A26 Linear Modulator Assembly, A26R7 (BAL)
Equipment
Synthesized Sweeper
HP 8340B Opt. 001
Pulse Generator
HP 8012B
Oscilloscope
HP 1741A
10:1 Divider Probe
HP 100040
Mixer
HP P/N 0955-0307
Digital Voltmeter
HP 3456A
Amplifier
HP 8447F
Low Pass Filter
HP P/N 91 35-0260
10 dB Attenuator
HP 8493C Option 010
Adapters:
APC 3.5 (f) to APC 3.5
(f)
HP P/N 5061-5311
(required if OUT is an HP 8340B)
APC 3.5 (f) to Type-N
(in)
HP P/N 1250-1 744
(required if OUT
is an HP 8341 B)
BNC (f) to Dual Banana
HP P/N 1251 -2277
BNC Tee
HP P/N 1250-0781
Procedure
If the OUT is equipped with Option 006, Delete Pulse Modulation, proceed directly to step 16.
DETECTOR SAMPLE AND HOLD BALANCE ADJUSTMENT
1. Connect equipment
as shown in Figure 5-64. Allow at least
30 minutes warmup.
NOTE
The A21, A25, and A26 PC boards must not be placed on extender
boards in this adjustment procedure. Also, the cables connected to
detectors All and A12 are especially designed for low capacitance and
only these cables may be used during adjustment procedures.
2. Set the oscilloscope as follows:
DISPLAY
CHOP
MODE
MAIN
MAGX5
ON
CH A
0.005 V/Div AC
COUPLED
CHB
5V/Div500hms
TIME/Div
2 jisec
Connect CH A probe to A26TP2 (DET)
5-122
Adjustments
HP 8340B/41B