Quick Tuning Checkout Procedure - Agilent Technologies 5517B Operation And Service Manual

8-63. If replacement of the clear optical window (which is cemented to the HP 5517B front panel) becomes necessary,
proceed with the following procedure:
a. Remove front panel and side covers as described in paragraph 8-57.
b. Remove mechanical parts MP7 and MP6 from front panel (MP3).
c. Remove old window from front panel (MP3) by applying steady pressure to its center with your
fingers.
d. Thoroughly clean old adhesive from now vacant hole in front panel (MP3).
e. Apply silicone rubber adhesive [such as Dow Coming's 3145 RTV (HP Part Number 0470-0357)] to
inside of hole in front panel (MP3).
f. Insert new window (MP11) in front panel (MP3) window hole by pushing in and twisting the window
(MP11). This procedure ensures that the adhesive spreads evenly.
g. Clean window thoroughly.
h. Allow adhesive 24 hours to cure before re-installing front panel on HP 5517B Laser Head.
8-64. The laser tube assembly consists of an aluminum housing, laser tube, magnets, telescope and the quarter-
wave/half-wave plate assembly. The telescope expands and collimates the beam. The quarter-wave plate and half-
wave plate establish the orientation of the two laser beam components.
8-65. HP 5517B TROUBLE ISOLATION 8-66. Quick
Tuning Checkout Procedure
8-67. The following procedure provides a means to quickly check the entire optical tuning subsystem of the laser
head. Before performing the procedure, read the information in paragraphs 8-28 through 8-41 to gain the necessary
background information to aid in interpreting the test results.
F] and F
2
8-68. This procedure consists of monitoring test point TP16 on A3 with an oscilloscope to determine the relative
amplitudes of Fj and F
properly and the heater is turned off, the traces on the oscilloscope will show switching to different levels as it
monitors the sampling of F| and F
correspond to Fj and F
2
8-69. To perform the quick isolation procedure, proceed as follows:
a. Observe the READY LED on the rear panel of the HP 5517B. If after approximately 6 minutes
from power-up (cold start), the LED begins flashing, you can assume that the clock, dividers,
state machine, warmup and power amplifier stages are working properly.
b. Remove the HP 5517B covers as described in paragraph 8-57.
Figure 8-12. Laser Tube Tuning Characteristics
with the heater turned off. If the sampler, photodiode, and amplifier are functioning
2
With continued observation of the trace switching, these levels which
2
will change amplitudes since the tuning is uncontrolled.
Figure 8-12
illustrates the effects of mirror spacing on