AMERITRON AL-572, Инструкция по эксплуатации

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Ameritron AL-572 Instruction Manual
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6. With the exciter's drive level still on zero, observe the 1000 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 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 meter (Ip) should suddenly indicate about 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 8 volts. This adjustment will limit the
amplifier's grid current to approximately 80 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 500 MILLIAMPERES AT THIS STAGE OF TUNING.
If either current exceeds these limits, reduce the exciter's power.
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 120 mA or a plate current of 600 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 dip slightly when the
grid current and output power peak.
Remove drive power and unkey exciter.
*11a. Increase the "ALC SET" voltage (if the ALC is connected) until 180 mA (18 volts) is
indicated. Apply full drive (not to exceed 100 watts) and adjust the "LOAD" and "PLATE"
controls for maximum RF output power. The grid current should not be allowed to go
above 200 mA at this stage. The plate current should not be allowed to exceed 750 mA
except during brief periods of tuning (15 seconds).