AMERITRON AL-811X Manuale di avvio rapido - Pagina 6
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CW PROCEDURE
Follow the instruction in numerical order. If the various meter
readings are different than the instructions, check the
connections from the exciter to the amplifier and make sure they
are correct. Consult the manual for the exciter if necessary. Be
sure the transformer is correctly wired for your line voltage. See
POWER CONNECTIONS
the
wiring details.
1.
Set the AL-811 front panel switches as follows:
OFF-ON to OFF
OPR-STBY to STBY
Ip-HV to HV
2.
Plug the line cord into the proper voltage outlet.
3.
Set the power switch to the ON position. the meter lamps
should light and the fan should start. Read the 2000 volt
scale on the multimeter.
nominal and no more than 1800 volts.
4.
With the amplifier still on STBY, tune the exciter into the
normal 50 ohm load according to the manufacturer's
instructions. Turn the exciter drive fully down after tuning.
5.
Place the amplifier bandswitch on the same band as the
exciter, the PLATE control in the dial range for the band
selected, and the LOAD control as indicated:
MHz
Plate
Load
1.80
1
3
1.90
2
4
3.5
4 1/2
3
3.7
5
4
4.0
5 1/2
4 1/2
7.0
7 1/2
4 1/2
7.3
7 1/2
4 1/2
instructions on page 4 for
It should indicate 1700 volts
MHz
Plate
Load
10.0
7
0
14.0
8 1/2
4 1/2
18.1
8 1/2
4
21.0
9
5
24.5
4
8 1/2
28.5
9 1/2
5
TUNE-UP
6.
With the exciter drive still at zero, place the HV-Ip switch
in the Ip position. Observe the 750mA scale. It should
read zero.
position.
7.
Key the exciter (no drive). The Transmit (XMT) LED
should light. Observe the plate current on the 750mA scale.
It should be 110mA.
NOTE: The no drive current will vary up to 25% due to
component and line voltage tolerances.
8.
Apply only enough drive to indicate a grid current of
100mA OR an Ip of no more than 450mA.
PLATE control for maximum output power. It is normal
for the plate current to dip at this point. If the grid current
goes over 150mA, reduce the drive at once. Unkey the
exciter.
9.
Observe the output on an external RF wattmeter. Increase
the drive until full exciter power (never to exceed 100
watts) or 200mA of grid current is achieved. Quickly adjust
the PLATE and LOAD controls for maximum output
power.
10. Reduce the drive until the desired output levels are
obtained.
NOTE: Rotating the LOAD control clockwise reduces grid
current for a given amount of drive. If the LOAD
control is set at too low a numerical setting, a severs
stress on tank components may occur. The PLATE
control should always be peaked for maximum grid
current or output power. Do not exceed 700mA of
plate current during tune-up.
Place the STBY-OPR switch in the OPR
Tune the
6