Acom 2000R Operating Manual page 15

When you intend to have a pause in operating, it is better to leave the amplifier in
STBY mode instead of turning it off, using the red colored
shortened by repeatedly turning on and off the tube heater supply.
However, if you unintentionally power-off the amplifier, it is best to switch it on
again immediately. When the pause is short (up to 1 minute) and the cathodes are
still warm, the warm-up period is shortened significantly, which reduces the waiting
time and prolongs the tube's expected life.
After the indicated period expires, all voltages are automatically applied to the tubes in the correct
sequence. At the same time the stepper motors tune the plate circuit to the frequency segment on
which the amplifier was used immediately before last switching it off. You hear "R" being sent in CW and
the MAIN MENU appears on the LCD (see example below):
The display informs you about the current state of the amplifier. The bargraph on the upper line indicates
the Exhaust Air temperature and each bar corresponds to 10 degrees centigrade. On the right-hand
side of the same line there is an indication for OPER and STBY mode.
The whole HF spectrum is split in 250 segments. Segment width increases with frequency and is 25kHz
on 160m, reaching 300kHz on 10m. You can use up to ten different antennas per frequency segment.
This could be very useful with narrow-bandwidth antennas.
The frequency segment on which the amplifier is tuned up (in MHz) is indicated on the left-hand side on
the display lower line. To the right of it is indicated the number of the antenna in use (in the example A1
- first) and next to it the tune type for this frequency segment and this antenna (in the example DEF -
Default or factory programmed). The amplifier may also be user-tuned by means of the AUTO sub-
menu as explained in Section 4-1.
b) If the VSWR of the antenna is acceptable (below 1.5:1), you may start operating the amplifier
immediately after pressing the OPR (Operate) button. The green LED-indicator next to the button
glows and you may transmit. The two LED-bargraphs indicate the power fed into the antenna (forward
power) and the power reflected from it (reflected power). The difference between the two is the real
output power delivered from the amplifier.
If you start transmitting on a frequency different from the indicated segment and the amplifier is in
OPER mode, it automatically senses your operating frequency, selects the corresponding segment, and
tunes up on it. This retuning takes less than 1 second and you are immediately ready to operate on the
new band. Example:
14
N O T E
N O T E
button. Tube life is