Acom 1010 User manual

ACOM 1010
HF Linear Amplifier
User's Manual
Installation, Operation
and Maintenance
July 2021
OUTSTANDING HF POWER PRODUCTS

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 2of 40 | S e c t i o n ABOUT DOCUMENTATION
July 2021
This manual is for electronic distribution mainly.
If you have it on paper and you no longer need it, please, recycle it!
The latest versions of our User's Manuals are available at
www.acom-bg.com

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n ABOUT DOCUMENTATION | Page 3of 40
ABOUT DOCUMENTATION
All ACOM documentation (including manuals, brochures, specifications, descriptions, presentations, video
materials, etc.) are based on the latest available information at the time of creation of our documents.
As we always strive to constantly improve and update our products, ALL PRODUCTS, PRODUCT
SPECIFICATIONS AND DATA ARE SUBJECT TO CHANGE. ACOM reserves the right to make changes and
improvements at any time without further notice or obligation to notify any person or organization of such
revisions or changes, made in order to improve the reliability, function, quality and design, and/or
performance of the ACOM products and services.
Further, this User's Manual is provided AS IS and ACOM shall not be liable for possible errors contained
herein.
This manual supersedes all previous editions, which thereby become invalid.
The cover images used in the manual are illustrative only.
We are continuously striving to improve our documentation, but nobody is perfect.
And our documentation is not an exception of this rule.
Have you found any errors or would you like to suggest changes in our documentation?
Please help us by sending your suggestions to the following e-mail address:
[e-mail]
The latest versions of our User's Manuals are available at
www.acom-bg.com
We highly recommend you to use this manual in electronic form as PDF-file instead of printed version. The
PDF-file is easy to read on any computer, tablet, smart phone or other similar device. In the PDF file you will
find the necessary information very fast due to context-oriented links (marked in orange) inside the file,
including context-linked Table of Content.
To open PDF-files you can use any free PDF viewer, for example:
•Adobe Acrobat Reader DC (https://get.adobe.com/reader);
•Foxit Reader (https://www.foxitsoftware.com/pdf-reader);
•Your web browser. Web browsers like Google Chrome, Firefox and Safari all have integrated
PDF readers.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 4of 40 | S e c t i o n ABOUT DOCUMENTATION
July 2021
Title of Documentation
ACOM 1010 HF Linear Amplifier
User's Manual
Installation, Operation and Maintenance
Type of Documentation
User's Manual
Purpose of Documentation
This manual explains Installation, Operation and Maintenance of the
ACOM 1010 HF Linear Amplifier.
Record of Revisions
Description
Release Date
Notes
ACOM 1010 User's Manual
-
First edition
ACOM 1010 User's Manual
-
Second edition
ACOM 1010 User's Manual
03.03.2016
Third edition
ACOM 1010 User's Manual
28.08.2020
Fourth edition
ACOM 1010 User's Manual
10.12.2020
Fourth edition, R02
ACOM 1010 User's Manual
19.07.2021
Fourth edition, R03
Validity
The specified data is for product description purposes only and may not be
deemed to be guaranteed unless expressly confirmed in the contract. All
rights are reserved with respect to the content of this manual and the
availability of the product.
Copyrights
© 2021 ACOM Ltd.
Copying this document, giving it to others and the use or communication
of the contents thereof without express authority, are forbidden.
Offenders will be held liable for infringement of any intellectual property
of ACOM Ltd. and all damages which may rise as a result.
Published by
ACOM Ltd.
Bulgaria | Bozhurishte 2227
Sofia-Bozhurishte Economic Zone | 6 Valeri Petrov Str.
GPS coordinates: 42.748616о| 23.209801о
Web: www.acom-bg.com
E-mail: [e-mail]
Note
This manual has been printed on chlorine-free bleached paper.

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n ABOUT DOCUMENTATION | Page 5of 40
Contents
ABOUT DOCUMENTATION ................................................................................................................................ 3
1. GENERAL INFORMATION........................................................................................................................... 7
1.1. Introduction and Description.......................................................................................................... 7
1.2. Owner Assistance............................................................................................................................ 8
1.3. Equipment Supplied........................................................................................................................ 8
1.4. Features........................................................................................................................................... 9
1.5. Safety Considerations, Explicit Definitions.................................................................................... 10
2. INSTALLATION.......................................................................................................................................... 13
2.1. Unpacking and Initial Inspection................................................................................................... 13
2.2. Line Voltage Selection................................................................................................................... 13
2.3. Amplifier Location Selection ......................................................................................................... 14
2.4. Connections................................................................................................................................... 15
3. POWER ON, CONTROLS AND INDICATORS.............................................................................................. 19
4. OPERATION.............................................................................................................................................. 21
4.1. Turning ON and OFF...................................................................................................................... 21
4.2. Changing OPERATE and STANDBY Modes..................................................................................... 22
4.3. RTTY Mode .................................................................................................................................... 22
4.4. Antenna Change............................................................................................................................ 22
4.5. Tuning............................................................................................................................................ 23
4.6. The Auto-Protection System ......................................................................................................... 26
5. MAINTENANCE ........................................................................................................................................ 27
5.1. Periodic Maintenance ................................................................................................................... 27
5.2. Cleaning......................................................................................................................................... 27
5.3. Fuse Replacement......................................................................................................................... 28
5.4. Tube Replacement ........................................................................................................................ 29
5.5. Simplified Schematic Diagram....................................................................................................... 30
5.6. Service Functions........................................................................................................................... 32
6. SPECIFICATIONS....................................................................................................................................... 33
6.1. Parameters.................................................................................................................................... 33
6.2. Functions....................................................................................................................................... 34

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 6of 40 | S e c t i o n ABOUT DOCUMENTATION
July 2021
6.3. Storage and Shipment................................................................................................................... 35
6.3.1. Storage Environment....................................................................................................... 35
6.3.2. Shipping Size and Weight ................................................................................................ 35
6.3.3. Transportation................................................................................................................. 35
6.3.4. Returning to the Service Provider ................................................................................... 35
6.4. Information on Disposing and Recycling of Old Electrical and Electronic Equipment.................. 36
NOTES.............................................................................................................................................................. 37
Figures
Figure 2-1 Rear panel - Connections ............................................................................................................... 16
Figure 2-2 Power rocker switch in OFF or ON position ................................................................................... 18
Figure 3-1 Front panel - Display and Controls................................................................................................. 19
Figure 4-1 Using TRI tuning aid........................................................................................................................ 25
Figure 5-1 Simplified Schematic Diagram........................................................................................................ 31
Figure 6-1 Packaging cardboard box ............................................................................................................... 35
Tables
Table 2-1 Amplifier Individual Data................................................................................................................. 13
Table 4-1 Approximate tuning preset ............................................................................................................. 24

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n GENERAL INFORMATION | Page 7of 40
1. GENERAL INFORMATION
Congratulations on purchasing one of the finest HF amplifiers in the world today.
ACOM is pleased that you have chosen one of our products, and we will endeavor to provide you with the
information and support you need to enjoy your purchase for many years.
We urge you to read all of the following materials before you embark on operating your new amplifier.
1.1. Introduction and Description
This manual explains:
•Installation
•Operation and
•Maintenance
of the ACOM 1010 HF linear amplifier.
The ACOM 1010 is a self-contained linear amplifier that covers all amateur bands, from 1.8 through
29.7 MHz. It provides over 700 W PEP of output power (or 500 W in continuous-duty operation) with less
than 60 W of drive. The amplifier is designed to tolerate SWR levels of up to 3:1 throughout its operating
range, and tuning is simplified by ACOM's exclusive True Resistance Indicator (TRI). Also, a built-in antenna
selector switch with two outputs is included to provide instant choice of antennas. Importantly, a variety of
system parameters are continuously monitored and available to the operator to assure safe and efficient
amplifier operation.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 8of 40 | S e c t i o n GENERAL INFORMATION
July 2021
1.2. Owner Assistance
If assistance is needed, you should contact your local dealerfirst. If necessary, your dealer will contact ACOM
for additional guidance.
If you still have an issue you need to discuss with one of ACOM's specialists, the contact information is as
follows:
ACOM Ltd.
E-mail: [e-mail]
Bulgaria | Bozhurishte 2227
Sofia-Bozhurishte Economic Zone | 6 Valeri Petrov Str.
GPS coordinates: 42.748616о| 23.209801о
1.3. Equipment Supplied
The ACOM 1010 amplifier and this User's Manual are shipped in a cardboard carton.

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n GENERAL INFORMATION | Page 9of 40
1.4. Features
•Easy to operate
The plate-load True Resistance Indicator (TRI) is an ACOM innovation that provides quick and precise
tuning, typically in less than 10 seconds. The AUTO-OPERATE function will return the amplifier to the
OPERATE mode automatically after each protection trip, saving time and avoiding manual switching.
•No antenna tuner needed
No external antenna tuner is required as long as the antenna SWR is 3:1 or lower. The amplifier will
perform the functions of an antenna tuner, enabling you to change antennas faster and use them over
wide frequency ranges.
•User-friendly and durable
This amplifier is both user-friendly and self-monitoring. It is designed to safely withstand up to 240 W
of reflected power, up to 100 milliseconds of drive spikes (RF "tails" after a PTT or KEY release), and
even operator tuning errors. It is also capable of operating at more than half its designed output
power at only 75% of nominal line (mains) voltage. Because it can tolerate deep voltage drops (down
to zero for 10 milliseconds) and 15% line voltage spikes, it is particularly suited for use in portable
environments, such as field days and DXpeditions.
•LED bar-graph display
The upper LED bar-graph always reads peak forward power (except for the service functions) while the
lower LED bar-graph is for the reflected power. LED warning indicators are provided for abnormal
conditions of grid 1, grid 2, and plate parameters.
•Antenna selection
Two antenna outputs are selectable on the front panel of the amplifier.
•Efficient tuning
Antenna matching can be achieved in less than 10 seconds and at a quarter of nominal output power,
which produces lower risk of interference to other stations and greater safety to the amplifier
components.
•Transceiver-independent
The amplifier operates without special signaling from the transceiver. It needs only "ground on TX"
and 60 W RF drive power to operate at full output power.
•Broadband input matching
Broadband input matching circuitry offers excellent loading characteristics for the driving transceiver,
from 1.8 MHz to 30 MHz.
•Single tube operation
A single Svetlana 4CX800A (GU74B) high-performance ceramic-metal tetrode with plate dissipation of
800 W (forced air cooling, grid-driven) is used for maximum efficiency.
•Permanent monitoring and protection of the plate and grids currents
The Bias Optimizer minimizes heat dissipated by the tube, assuring tube longevity.
•High voltage protection
Design of the high-voltage power supply eliminates the danger of turn-on transients affecting sensitive
devices connected to the same line (mains) circuit. Moreover, the amplifier can be configured for 8
different nominal line voltages: 100, 110, 120, 200, 210, 220, 230, or 240 VAC, 50 or 60 Hz.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 10 of 40 | S e c t i o n GENERAL INFORMATION
July 2021
1.5. Safety Considerations, Explicit Definitions
The ACOM 1010 HF Linear Amplifier is a Safety Class I unit regarding protection against electric shock. The
third grounding lead of its mains cord (which is colored yellow with two green stripes) and the ground stud
on the rear panel of the amplifier (marked GND, see ) must be connected to the station's grounding system
for safe operation.
The amplifier is designed to meet international safety standards and complies with CE safety and
electromagnetic compatibility requirements, as well as FCC regulations.
This User's Manual contains information, warnings (signal words Danger, Warning, Caution and Notice) and
instructions, related to hazards, that should be followed by the user in order to ensure safe operation and
to keep the amplifier in a safe working condition at all times.
The EXPLICIT DEFINITIONS described below apply to this User's Manual:
DANGER
These notes call attention to a procedure or instructions which, if not correctly
performed, will result in serious personal injuries and even death.
WARNING
These notes call attention to a procedure or instructions which, if not correctly
performed, could result in serious personal injuries and even death.
CAUTION
These notes call attention to a procedure or instructions which, if not correctly
performed, could result in minor or moderate personal injuries.
NOTICE
These notes call attention to a procedure or instructions which, if not correctly
performed, could result in property damage or equipment damage not exclusively to
the amplifier but also to connected equipment.

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n GENERAL INFORMATION | Page 11 of 40
Information notes described below apply to this User's Manual:
These notes highlight operating procedures or practices that may improve equipment
reliability and/or personnel performance, or to emphasize a concept.
ORANGE TEXT as LINKS
marks all internal links in the document between Sections, Figures, Tables, etc. for your
convenience.
The safety instructions contained in this User's Manual feature specific signal words
(Danger, Warning, Caution or Notice) and, where required, a safety alert symbol, in
accordance with actual standards ISO 3864 or ANSI Z535.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 12 of 40 | S e c t i o n GENERAL INFORMATION
July 2021
PRECAUTIONS:
DANGER
The amplifier works with high voltages up to 3000 V, which are LETHAL!
For your safety, pull the amplifier power plug out of the mains wall outlet and WAIT AT
LEAST 30 minutes EACH TIME BEFORE you remove the cover of the amplifier. Do not
touch any part inside while the amplifier is open because some residual voltages may
still be present.
DANGER
Never allow anyone, ESPECIALLY CHILDREN, to push or put anything into holes in the
case - this will cause electric shock. NEVER TOUCH AN ANTENNA or antenna insulators
during transmission or tuning - this may result in an electric shock or burn. NEVER
EXPOSE the amplifier to rain, snow or any liquids. AVOID placing the amplifier in
excessively dusty environments or in direct sunlight. DO NOT OBSTRUCT AIR INTAKE
(bottom) and EXHAUST (top cover) areas of the amplifier. Keep a minimum clearance
distance of 50 cm (20 inches) above the exhaust opening.
WARNING
Do not undertake on your own repairs or changes in hardware or software of the
amplifier in order not to endanger your or other's health and life and not to damage the
amplifier and the equipment connected with it, not covered by warranty. The
manufacturer is not liable for another's actions and responsibility shall be assumed by
the doer.
WARNING
To avoid damage (not covered under warranty) read the Section 2 INSTALLATION of this
User's Manual carefully. If you have any doubts about the installation, operation or
safety of the amplifier, please, consult your dealer.

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n INSTALLATION | Page 13 of 40
2. INSTALLATION
2.1. Unpacking and Initial Inspection
Before you install your amplifier, thoroughly read this manual.
First, carefully inspect the cardboard carton and its contents for physical damage. ACOM
ships amplifiers in highly protected containers, but it cannot assure that mistreatment
by shippers will not occur. If damage is evident, notify your dealer immediately. Delay
may void the carrier's warranty.
Keep all packing materials for possible future amplifier shipment (see Section 6.3.4 Returning to the Service
Provider).
2.2. Line Voltage Selection
NOTICE
To avoid damage, which will not be covered under your warranty, check carefully to be
certain that the voltage for which the amplifier is set corresponds to your mains nominal
voltage.
Normally, the amplifier is supplied set for a nominal line voltage of 240 V. If your mains voltage is not 240 V,
you must contact your dealer for instructions. The only exception to this is if the unit has been custom
ordered, in which case the voltage selection will be noted in the Table of Individual Data (see Table 2-1
Amplifier Individual Data).
Table 2-1 Amplifier Individual Data
AMP SN:
Tube SN:
Voltage Selector Position
VAC
Table 2-1 Amplifier Individual Data
The amplifier power supply can be configured for 8 different nominal line voltages:
100, 110, 120, 200, 210, 220, 230, or 240 VAC, 50 or 60 Hz.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 14 of 40 | S e c t i o n INSTALLATION
July 2021
2.3. Amplifier Location Selection
CAUTION
The weight of the unit is about 17 kg, which should preferably be handled by two
persons.
Position the amplifier near the place where it will be used. You will need an easy access to the command
knobs and indicator's area, as well as to the rear panel cabling.
No magnetic-field sensitive devices (such as microphones) should be located next to the right side of the
amplifier because its power transformer is located there. It is advisable to position the amplifier to the right
of your transceiver.
No temperature-sensitive devices should be located above the exhaust hot air area. This means that the
amplifier should not be located under a shelf or other structure that could impede the free movement of
air away from the amplifier.
NOTICE
Do not under any circumstances obstruct the air intake (bottom) and exhaust (top
cover) areas of the amplifier. Keep a minimum clearance distance of 50 cm (20 inches)
above the exhaust opening.
NOTICE
Do not leave accidental paper, cloth or other lightweight pieces around and under the
amplifier. They may be drawn in by the cooling air stream and block the vents. This will
lead to overheating and accelerated material aging, not covered by the warranty.

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n INSTALLATION | Page 15 of 40
2.4. Connections
Please, see Figure 2-1 Rear panel - Connections.
Connection to your station must be accomplished in the order described below, before you apply mains
voltage to the amplifier.
Before you connect the amplifier to external grounding, you should advise with a
licensed electrician and confirm such kind of connection is allowed by your national and
local electrical code, safety rules, and regulations in force. Simultaneous connection to
the earth grounding and protective earth may be inadmissible or may fall under special
requirements in some countries!
DANGER
Never use the gas installation for grounding. This can cause an EXPLOSION!
DANGER
Do not use the steam-heating or water-supply network for grounding! You may expose
to dangerous voltage not only yourself but also other people using the same installation.
a) GND stud
First, connect the wing-nut grounding stud of the amplifier (on the rear panel, marked GND) to the station's
grounding system (see Figure 2-1 Rear panel - Connections, Pos. (a)).
WARNING
Note that the grounding system may have to withstand currents over 15 A with
insignificant voltage drop on it. Therefore, it may be necessary to improve it
considerably, i.e., to become less resistive, with heavier leads and lower-resistive ground
path. The grounding leads should be at least 4 mm² (AWG 11 or SWG 13).

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 16 of 40 | S e c t i o n INSTALLATION
July 2021
Figure 2-1 Rear panel - Connections
Figure 2-1 Rear panel - Connections
b) RF INPUT socket
Connect a suitable coaxial cable from the transceiver output to the amplifier RF INPUT SO-239 socket (see
Figure 2-1 Rear panel - Connections, Pos. (b)), using PL-259 plug.
NOTICE
In order to avoid a damage, turn off your transceiver's internal antenna tuner.
c) ANT1 and ANT2 sockets
NOTICE
If this is the first time you will use a power amplifier in your station, pay attention to the
coaxial cable type from the amplifier's output to the antenna. It must handle the
increased power safely, particularly on the 10-meter band. It is suggested that, at a
minimum, RG8X (including RG8MINI, RK50-4-11, RK50-4-13) or, even better, RG213
(including RK50-7-11) coaxial cable be used.
Connect a suitable coaxial cable with a PL-259 plug from the amplifier output ANT1 or ANT2 (see Figure 2-1
Rear panel - Connections, Pos. (c)) to the antenna selector or tuner, or to the antenna for the respective
frequency band.
d)
f)
c)
c)
b)
a)
e)
5

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n INSTALLATION | Page 17 of 40
d) KEY-IN socket
This is the amplifier's input for receive/transmit control from the transceiver.
The transceiver controls the amplifier from receive mode into transmit mode (RX/TX) by grounding of the
KEY-IN input.
Run a shielded cable from the "ground on transmit" socket or terminal on your transceiver to the amplifier
KEY-IN socket (see Figure 2-1 Rear panel - Connections, Pos. (d)). The KEY-IN socket uses a standard RCA
phono plug.
Voltage on the KEY-IN socket does not exceed 12 V and the current is below 6 mA.
Your amplifier will not work if KEY-IN input is not connected properly.
Transceiver producers give different names to this output and they are for instance
TX-GND, SEND, T/R-LINE, PTT, etc. Some transceivers require that "ground on transmit"
is implemented via a software command, or by changing the setting of a switch on the
rear panel, or interior of the transceiver. Check your transceiver's manual.
e) Main fuses
NOTICE
Make sure you check whether the main fuses installed in your amplifier (see Figure 2-1
Rear panel - Connections, Pos. (e)) correspond to your local mains nominal voltage and if
necessary, replace them as described in Section 5.3 Fuse Replacement!
WARNING
If your amplifier is only fitted with one line (mains) fuse, it is suitable for European
Community ONLY. Your dealer will check that your amplifier is correctly fused before it is
shipped to you. Customers should check with a qualified electrician if the amplifier is to
be used outside the country in which it was purchased.
f) The IEC 320 Power inlet
Please, see Figure 2-1 Rear panel - Connections, Pos. (f).
Due to the different standards in different countries, the power supply cable and mains plug are supplied
and mounted by the dealer. He connects to the mains cord end a standard mains supply plug which meets
the Safety Class I unit standard in your country.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 18 of 40 | S e c t i o n INSTALLATION
July 2021
g) Preparation of wall outlet
WARNING
Before connecting the amplifier to your mains supply using a licensed electrician, check
that the supply is correctly wired, and is adequate for power consumption up to
1200 VA. Make certain that the grounding lead is connected properly and that it has a
cross section not less than the cross section of the phase conductor in the wall outlet for
the amplifier.
It is preferable that you use the wall outlet closest to the source. The installation leads should be at least
1.0 mm² (AWG 17 or SWG 18) at operating 200-240VAC and 1.5 mm² (AWG 15 or SWG 17) at 100-120VAC
(recommended values if there are no stricter requirements by your local standard).
Check that the panel fuse has a free capacity for the additional load from the amplifier as specified in
Sections 5.3 Fuse Replacement and 6.1.i) Mains Power Consumption.If you connect the amplifier to a different
mains outlet, be sure that you check it, too.
Make sure the main Power switch (marked "ON", see Figure 3-1 Front panel - Display and Controls) on the
front panel is in OFF position (see Figure 2-2 Power rocker switch in OFF or ON position) and insert amplifier's
mains plug into the wall outlet prepared for it. The amplifier remains switched off (with the "ON" indicator
dark).
Figure 2-2 Power rocker switch in OFF or ON position
OFF position
ON position
Figure 2-2 Power rocker switch in OFF or ON position

User's Manual | ACOM 1010 | HF Linear Amplifier
July 2021
S e c t i o n POWER ON, CONTROLS AND INDICATORS | Page 19 of 40
3. POWER ON, CONTROLS AND INDICATORS
NOTICE
Do not turn the amplifier on for at least 2 hours after unpacking it in the room where it
will be used. Pay particular attention when you move it from a very cold into a warm
place - condensation is likely and this could result in damage to the high voltage circuits.
In such a case, wait at least 4 hours. A similar effect can occur after a rapid warming of
the operating room (for instance after switching on a powerful heater in a cold shack).
NOTICE
In order to avoid any damage (not covered by the warranty), check carefully to be
certain that the voltage for which the amplifier is set corresponds to your mains nominal
voltage (see Section 2.2 Line Voltage Selection and Table 2-1 Amplifier Individual Data).
After following all instructions in Section 2 INSTALLATION, you may turn on the main power switch (marked
"ON") on the front panel (see Figure 3-1 Front panel - Display and Controls and Figure 2-2 Power rocker switch in
OFF or ON position). The green LED indicator above the switch will illuminate.
Figure 3-1 Front panel - Display and Controls
Figure 3-1 Front panel - Display and Controls
You will note that the upper LED bar-graph always reads peak forward power, except for the service
functions (see Section 5.6 Service Functions). The 800 W scale resolution is 50 W. Note also that levels below
50 W may be not detected.
The lower LED bar-graph will indicate reflected power up to 240 W. The scale resolution is 30 W.

User's Manual | ACOM 1010 | HF Linear Amplifier
Page 20 of 40 | S e c t i o n POWER ON, CONTROLS AND INDICATORS
July 2021
The OPER button alternatively switches between the OPERATE and STANDBY modes once the amplifier has
completed its 150-second warm-up period (see Section 4.2 Changing OPERATE and STANDBY Modes).
The RTTY button reduces the output power of the amplifier to 500 W (see Section 4.3 RTTY Mode).
The button labeled A1-A2 (see Section 4.4 Antenna Change) changes the antenna output to either Antenna 1
or Antenna 2, according to the operator's choice. It is the operator's responsibility to connect suitable
antennas to the ANT1 and ANT2 connectors (see Figure 2-1 Rear panel - Connections, Pos. (c)).
The red TX LED illuminates whenever the KEY-IN input is keyed (closed to ground), i.e., when the
transceiver goes into the transmit mode (see Section 2.4.d) KEY-IN socket).
The BAND knob controls the band switch, and LOAD and TUNE are used to adjust the respective variable
air capacitors in the amplifier's output circuit. The settings of these three controls must be changed at each
band change as well as when an antenna is changed. The three LED indicators located above the knob
LOAD are called the "TRI tuning indicator" and they are used to achieve antenna impedance matching
during a re-tune procedure (see Section 4.5 Tuning).
NOTICE
Do not switch the BAND switch knob while transmitting with the amplifier! Hot
switching (while transmitting) will eventually destroy the band switch, not covered by
the warranty!
There are three warning yellow LED indicators and one fault red LED indicator located in the bar-graphs
area. The following describe the error conditions and the correct responses (except for the service
functions - see Section 5.6 Service Functions):
•G1 - when illuminated, a control-grid overload condition exists.
Reduce the drive power for safe operation;
•G2 - when illuminated, a screen-grid overload condition exists.
Reduce the drive power and/or refresh the tuning for safe operation (see Section 4.5 Tuning);
•IP - when illuminated, a plate current overload condition exists.
For safe operation reduce the drive power and/or refresh the tuning (see Section 4.5 Tuning);
•F- when illuminated, the amplifier automatic protection has tripped.
If Fis accompanied with one of the G1, G2, or IP condition indicators, the cause of the
protection trip will be evident. When F alone is illuminated, check the keying wiring (see
Section 2.4.d) KEY-IN socket). See Section 4.6 The Auto-Protection System for details about the
auto-protection system.