SRS Labs SR715, Руководство пользователя

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MAINETENANCE
6-5
BUILT IN FIXTURE
CLEANING Several times a year, both the radial and axial test fixtures should be examined
for any build up of waxy coatings from lead material. If the contacts appear dirty
they should be cleaned. To clean both fixtures, use a thick piece of paper or
cardboard moistened with isopropyl alcohol or a mild cleaning solvent. Slide it
back and forth between the contacts. Repeat until no further residue comes off.
Allow the fixture to dry before making measurements.
REMOVING LEADS The radial fixture has a lead catcher on the bottom so any leads or contaminants
that fall into the the fixture do not fall inside the unit. Cleaning this requires
removing the top of the unit and detaching the fixture.
Removing the top
Turn off the power and unplug the unit from the AC power. Remove any parts or
adapters from the fixture. Next remove the four screws located on the bottom
corners of the unit. Place the unit right side up on its feet and gently slide the
plastic top off of the metal base. It is necessary to slide the top gradually off of the
fixture and the back panel since it fits tightly. When the top is removed, stand it on
its left side near the unit to avoid damaging the front panel cables. To replace the
top, reverse these steps taking care to align the top over the fixture and rear
panel. Finally, replace the four screws.
After the top is removed, remove the four screws that hold the fixture mounting
bracket to the PCB (printed circuit board). Use a 1/4" wrench to remove the nuts
that hold the fixture to the mounting plate. Slide the plastic lead catcher down until
the leads can be removed. Do this to one half of the fixture at a time to eliminate
confusion. Slide the lead catcher back up to the fixture and replace the nuts.
Attach the mounting bracket to the PCB and replace the top.
It may be easier to completely detach the fixture from the PCB before trying to
remove the lead catcher. See the section on removing the fixture and then follow
the directions above for cleaning out any leads.
CHANGING RADIAL
FIXTURE CONTACTS If the contacts become badly worn or too dirty to clean, it is necessary to replace
them. Contact SRS for replacement contacts. Changing the contacts will involve
removing the top and detaching the fixture completely from the PCB. This
requires several tools and soldering ability.
Tools required: 3/16", 1/4" and 9/32" wrenches or nutdrivers
Phillips screwdriver
Wire cutters
Soldering iron and solder
Removing the Fixture
Remove the top of the unit as described above. Detach the two ribbon cables and
lugged wire from the main board. Set the lid to one side. If present, remove the
GPIB/Handler option board, including the rear panel bolts. (This requires the
9/32" and 3/16" wrenches for the GPIB and Handler connector.) Remove the
3/16" bolts for the RS232 connector. Next remove the 12 screws holding the PCB
to the chassis and the two screws on the bottom right rear of the unit. Rotate the
front of the board up so the bottom is accessible. Desolder the leads that run
from the fixture to the board. Turn the board right side up, remove the four screws
holding the fixture mounting bracket to the PCB and lift the fixture mounting
bracket off.