Harris DiamondCD Series, Техническое руководство

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5-24 888-2463-001 3/6/08
WARNING: Disconnect primary power prior to servicing.
Diamond Series™
Section 5 Maintenance and Alignments
If this happens the following procedure should be performed to re-bias the pallet.
If the proper bias currents cannot be achieved, then the pallet should be replaced.
STEP 1
Shut off AC power to the driver with the ac switch on the rear of the
driver.
STEP 2
Connect a 50-ohm termination to the SMA input and output connectors
on the rear of the DD-1 Driver.
STEP 3
On the Driver Control Board, move JP9 to the 1-2 position and JP12 to
the 2-3 position. See Figure 5-9 for location of jumpers.
STEP 4
Turn R59 RF Amp Bias Adjust on the Driver Control board fully CCW
(ten-turn pot). See Figure 5-9 for location of R59.
STEP 5
Remove the cover from the amplifier pallet and turn both bias pots on
the pallet, R7 and R10, fully CCW for minimum bias (they are the only
potentiometers on the pallet and are shown in Figure 5-8).
Figure 5-8 Driver Pallet Bias Pots, R7 & R10
STEP 6
Turn on the AC supply and enable the Control board by pressing S1, the
driver ON switch on the driver Control board. See Figure 5-9 for
location of S1.