AMERITRON AL-80B, Инструкция по эксплуатации

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AL-80B Instruction Manual
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6. With the exciter's drive level still on zero, observe the 750 mA Ip scale on the left hand meter. It
should indicate zero (0) amperes.
7. Place the "STBY-OPR" switch in the "OPR" position. Place the exciter in the transmit mode
with no RF output. The red "XMT" LED should light and the plate current (Ip on the left meter)
should be close to zero (0).
8. With the exciter in the transmit mode, apply a very low amount of RF drive power (about 100
mW). The plate current (Ip) should suddenly increase to nearly 100 mA.
Note:
Currents may vary up to 25% due to component and line voltage tolerances. If the
current in this step is higher than expected, the RF level from the exciter may be
too high.
If the exciter does not allow adjustment to very low CW power levels, the exciter can be placed
in the SSB mode and the audio (microphone) gain control advanced from minimum while
speaking until the plate current (Ip) just flickers upwards. The plate current (Ip) should be
around 100 mA on these flickers.
9.
Place the "MULTIMETER" switch in the "ALC SET" position. Adjust the front panel "ALC
SET" control until the multimeter indicates 10 volts. This adjustment will limit the amplifier's
grid current to approximately 100 mA.
STEPS 10a and 11a REQUIRE A CONNECTION FROM THE AMPLIFIER'S ALC OUTPUT TO
THE EXCITER'S ALC INPUT.
STEPS 10b and 11b SHOULD BE USED IF THE EXCITER AND AMPLIFIER ALC LINES ARE
NOT CONNECTED.
Note: Step 10 requires the simultaneous observation of the plate current (Ip) and the
grid current (Ig).
10a. If the ALC line is connected, adjust the exciter's drive or power output control to maximum.
NEVER ALLOW THE GRID CURRENT (Ig) TO EXCEED 120 mA OR THE PLATE
CURRENT (Ip) TO EXCEED 400 MILLIAMPERES AT THIS STAGE OF TUNING. If either
current exceeds these limits, reduce the 'ALC SET' control. Adjust the 'PLATE' control for
maximum output power. The plate current (Ip) of the amplifier and the output power of the
exciter should dip (decrease) when this adjustment is made.
10b. If the ALC is not connected, place the exciter in the transmit mode and gradually increase the
drive until a grid current of 100 mA
or a plate current of 400 milliamperes (whichever is
higher) appears. The "PLATE" control should be adjusted until maximum grid current and
maximum RF output power appear. The plate current (Ip) should now dip slightly. The drive
power should be removed.