500 WATT RADIOBEACON TRANSMITTER
ND2000A-02x-xx0
Page 6-9
15 October 2004
(c) Unsolder gate, source and drain leads from the
adapter PWB, using a solder removal system
and then remove power MOSFET. Ensure
solder is not splattered on the chassis or between
the terminals on the adapter PWB.
(d) Remove and retain the insulating sleeve on the
drain lead of the power MOSFET just removed.
Ensure hole in metal chassis surface under an
insulating washer and an insulating pad is free from
burrs or any sharp projection that could damage the
insulating washing or insulating pad.
(e) Secure hardware securing the adapter PWB to
the chassis.
(f) Measure, using an ohmmeter, resistance
between each of the adapter PWB's three printed
wiring terminals and ground. Resistance
measured should be an open circuit for each
situation.
(g) If the resistance measured in step (f) is not an
open circuit, adjust the position of the adapter
PWB to obtain an open circuit between all three
terminals and ground.
(h) Position the original (or an identical) insulating
washer on chassis where power MOSFET will
be installed; ensuring hole in insulating washer
is aligned with mounting hole on the metal
chassis.
(i) Install power MOSFET using hardware
removed in step (a). Do not fully tighten the
hardware.
(j) Solder the gate and source leads to the
appropriate adapter PWB terminals. Trim the
power MOSFET's leads to prevent shorting to
the drain terminal.
(k) Install the insulating sleeve removed in step (d)
to the drain lead on the power MOSFET.
(l) Loosen hardware securing the adapter PWB to
the chassis.
(m) Solder the drain lead to the appropriate adapter
PWB pad.
(n) Torque hardware to five inch-pounds (0.57
Newton-meters or 0.58 kilogram-meters).
(o) Perform a function test as described in
paragraph 6.7.4.
