Acom 1000, Руководство пользователя, Страница: 27 / 52

User's Manual | ACOM 1500 | HF + 6 m Linear Amplifier
August 2021 S e c t i o n OPERATION | Page 27 of 52
NOTICE
Do not switch the ANTENNA or BAND switch knob while tuning or transmitting with the
amplifier! Hot switching will eventually destroy the BAND switch, not covered by the
warranty!
NOTICE
When tuning, never apply continuous drive longer than 3 (three) minutes without
pausing at least 1-2 minutes to allow the tube to cool.
It is recommended that for initial tuning a free frequency in the middle of the band be selected (make sure
the frequency is not being used by others so that you do not make QRM).
First, with
no drive power applied , select the band and correct antenna number. Then, use
Table 4-1
Approximate tuning presets
in order to achieve an approximate preset for both TUNE capacitor and LOAD
capacitor knobs settings:
Table 4-1 Approximate tuning presets
Band, MHz Tune Knob Dial Load Knob Dial
1.800 - 2.000 55 - 42 75 - 60
3.500 - 4.000
59 - 45 73 - 60
7.000 - 7.300 56 - 50 65 - 57
10.100 - 10.150
15 - 14 25 - 24
14.000 - 14.350
64 - 52 30 - 29
18.068 - 18.168
74 - 68 70 - 68
21.000 - 21.450 26 - 20 47 - 45
24.890 - 24.990
72 - 70 60 - 59
28.000 - 29.700 35 - 21 45 - 39
50.000 - 54.000
32 - 16 20 - 15
Table 4-1 Approximate tuning presets
b) Selecting the plate-load True Resistance Indicator (TRI) tuning aid
You may select the TRI scale in three different ways:
•
By pressing the PREV + NEXT buttons simultaneously for a moment.
This will insert a 6 dB attenuator between the driver and the amplifier's input (the ATT LED
will light), so you will not need to reduce the drive power during tuning. Press
PREV + NEXT
buttons momentarily again to switch the attenuator off the input and to return to the old
screen. If you use any of
PREV or NEXT buttons only, the attenuator would be switched off
too, but the information screen would change to respectively previous or next;