7.0 OPERATION
If the ALPHA 89 already is tuned and loaded for the operating frequency, it is necessary only to turn
on the amplifier, wait 3 minutes for tube warm-up time delay to complete, then switch to OPERATE
and apply drive. Before operating on a frequency or band different from that previously used, the 89
must be re-tuned by the operator. Re-tuning is a simple process that takes only a few seconds.
7.1 Preparation forALPHA 89 Tuneup
a) Press POWER ON button. Select preliminary BAND, TUNE, and LOAD control settings from the
"tuneup settings" chart, page 14.
b) When the three minute tube warm-up cycle ends, the red WAIT LED will extinguish. Depending
upon the setting of the OPR-ST13Y (operate-standby) switch, the appropriate status LED above it will
then light. Set the switch to STBY (standby); the STBY LED should then be illuminated. -) Set
transceiver to provide a steady unmodulated RF carrier (e.g., CW, AM, or RTTY/FSK).
d) Determine proper control settings for transceiver peak output of 50 watts. The ALPHA 89's builtin
drive power wattmeter may be used to measure and set transceiver power. To do this, first put the
amplifier in ST13Y so transceiver power is bypassed to the antenna. Then press the multimeter IP and
RV buttons simultaneously; the green LEDs in both buttons will illuminate. Driving power is indi-
cated on the 0-1.5 scale with full scale = 150 watts.
e) Adjust transceiver output to approximately 50 watts, note its power output control setting, then
reduce output to ZERO. NOTE: Most transceivers have an internal drive (or "processor out") control
which determines the internal ALC voltage. This must be adjusted according to the manufacturer's
instructions to avoid overdrive and distortion. f) Set the amplifier multimeter to Ip. The bargraph will
read at or near zero until drive is applied. g) Switch the amplifier from STBY to OPR (operate).
h) Set the SSB-CW switch to SSB. (Tuning should be done with the amplifier in the SSB (linear) mode
regardless of intended emission type. i) Set transceiver to transmit (manual lock-key, MOX, or PTT).
7.2 Normal tuneup using the TUNE meter
To tune up for nominal peak RF output of 1500 watts the goal is to adjust LOAD and TUNE controls
alternately until the lighted TUNE LED is positioned at the mid-scale "V" mark. Proceed as follows:
a) Preset the ALPHA 89's BAND, TUNE, and LOAD controls to the positions given in the "tuneup
settings" chart on page 14.
b) Select the multimeter TUNE function and apply approximately ten watts drive. (The TUNE LED
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