HP 5305 B, Operating And Service Manual

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9E-5-14. INTEGRATED CIRCUIT REPLACEMENT. Two
methods are recommended for removing integrated circuits:
a. Solder Gobbler. Solder is removed from board by a
soldering iron with a hollow tip connected to a vacuum
source. The IC is removed intact, so it may be reinstalled
if diagnosis is wrong.
b. Clip Out. This method is used when an IC is proven
defective. Clip leads close to case, apply heat, and
remove leads with long-nose pliers. Clean board holes
with toothpick and cleaning solution.
9E-5-16. The 5305B has two adjustments; Channel A and
Channel B. The adjustments should be made when the in-
cabinet performance test indicates the need, or when repairs
are made which would affect the adjustment settings.
Model 5305B
Maintenance
9E-5-18. The following steps outline proper adjustment
procedure for the Channel A amplfier.
a. On 5305B, set RANGE to A, RESOLUTION to 1K,
and ATTENUATOR to MIN.
Figure 9E-5-2. Test Setup for 1300 MHz Adjustment
9E-5-5
9E-5-15. ADJUSTMENTS
b. Set A2R13 and A1R71 to full ccw. Set A2R22 to mid-
range.
c. Connect 5300B/5306A voltmeter positive lead to J2
pin 5 and negative lead to rear panel.
d. Adjust A1R79 for 15V reading.
e. Connect test setup shown in Figure 9E-5-2.
NOTE
If meter on 8660B/86602A is calibrated, a 3
foot coaxial cable may be substituted for the
power splitter and power meter. Determine
the drop in cable ( ≈ 1 dB).
9E-5-17. CHANNEL A ADJUSTMENTS
f. Set signal generator to 1.29999999 GHz at 30 mV.
g. Adjust A2R22 for maximum sensitivity. (Reduce
signal level until A2R22 is adjusted for maximum
sensitivity.)
h. Set signal generator to 90 MHz.
i. If counter displays a steading reading of 00270.XXX
MHz, adjust output level of generator until counter
reads 00268.XXX MHz.
j. Adjust A1R71 cw until count light (C) stops blinking.