OM POWER OM2000A+ User manual

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MADE IN SLOVAKIA
WWW.OM-POWER.COM
OM Power, s.r.o. 93030 Báč126,
SLOVAKI A
Co n t a ct : + 4 2 1 905 321 410
e-mail : [e-mail]
e-mail : om-power@om-
power.com
OM2000A+
SHORTWAVE PLUS 50 MHz
POWER AMPLIFIER

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TABLE OF CONTENTS
1. GENERAL INFORMATION .................................................................................. 4
1.1. Introduction …………………………………………………………………. 4
1.2. Specification …………………………………………………………………. 4
1.2.1. Parameters …………………………………………………………. 4
1.2.2. Protection Circuits …………………………………………………………. 5
1.2.3. Features …………………………………………………………………. 5
1.2.4. The Advantages of OM2000A+ …………………………………………… 5
2. SAFETY INSTRUCTIONS …………………………………………………………. 6
3. GENERAL DESCRIPTION …………………………………………………………. 7
3.1. HF Compartment …………………………………………………………………. 7
3.2. Power Supply …………………………………………………………………. 8
3.3. Safety Devices …………………………………………………………………. 8
4. INSTALLATION ………………………………………………………. 9
4.1. Grounding …………………………..…………………………. 10
4.2. Coaxial Cable ………………………………………………………. 10
4.3. Control Cable ………………………………………………………. 11
4.4. Cooling ………………………………………………………. 11
5. OPERATION …………….…………………………………………………. 12
5.1. OM2000A+ Front Panel ………………………………………..……. 12
5.2. OM2000A+ Control ……………………………………………………… 13
5.3. Preparing for operation ……………………………………………….… 21
5.4. Operation mode ……………………………………………………. 27
6. MAINTENANCE ……………………………………………………. 31
6.1. Indication of Fault Conditions ………………………………………… 31
6.2. Fuse Replacement ……………………..……………………………. 33
6.3. Tube Replacement ……………………………………………………. 33
6.4. Cleaning ……………………………………………………. 33

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7. APPENDIX ……………………………………………………………. 33
7.1. Primary AC selection …………………………..………………………. 33
7.2. Removing the HV Transformer ………………………………………….. 35
7.3. Controlling OM200A+ with FLEX Radio Series 6xxx …..…………………. 36
7.4. OM2000A+ Remote Control ………………………………………………. 38
7.5. Remote Control using own public IP Address ........................................ 42
7.5.1. Changing OM2000A+ connection settings ............................................ 42
7.5.2. Setting up in the Remote software .......................................................... 43
7.5.3. Remote Control without own IP Address, behind a router ..................... 44
7.6. OM2000A+ firmware upgrade …………………………………………….. 45
7.7. Icom connection with OM2000A+ ………………………………………… 49
7.8. Yaesu plus BPF plus ANT Switch connection with OM2000A+ ….……. 50
7.9. Control panel connectors pin-out …………………………………………… 51
7.10. Block Diagram of the OM2000A+ Power Amplifier ………..…………… 55
7.11. Troubleshooting ………………………………………………………………. 56
FCC ID: X8NX8NOM2000 for US Market

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1. GENERAL INFORMATION
1.1. Introduction
he OM Power model OM2000A+ is designed for all short wave amateur bands from 1.8 to 29.7
MHz (including WARC bands) plus 50 MHz and all modes. It is equipped with a ceramic
tetrode FU-728F.
1.2. Specification
1.2.1. Parameters
Frequency Coverage Amateur Bands 1.8 – 29.7 MHz including WARC + 50 MHz
Power Output 2000+ W in SSB/CW on HF bands, 1500 W in CW/SSB on 6m
1500 W in RTTY,
1500W PEP for US models
Input Power Usually 40 to 60W for full Output Power
Input Impedance 50 Ohm, VSWR < 1.5 : 1
Power Gain 15 dB
Output Impedance 50 Ohm unbalanced
Maximum Output SWR 3 : 1
SWR protection Automatic switching to STBY, when reflected power
is 350W or higher
Intermodulation distortion 32dB below nominal output
Suppression of harmonics < -50 dBc; <-70dBc on 50 MHz
Tubes FU-728F Ceramic tetrode
Cooler Centrifugal blower + Axial blower
Power supply switchable 220, 230, 240 V 50 Hz (230, 240, 250V 60 Hz for US
models)
Transformers One toroidal transformer 3kVA
Dimensions 390 x 195 x 370 (width x height x depth in mm), 15.3” x 7.7”x 14.5”.
Weight 24 kg (53 lb)
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1.2.2. Protection Circuits
There are several protection circuits used in the amplifier. They are activated when one or more
parameters exceed defined values or some unwanted condition occurs.
•VSWR too high
•Anode current too high
•Anode voltage error
•Screen current too high
•Screen voltage error
•Grid current too high
•Grid voltage error
•Heating voltage error
•Mistuning of PA
•Temperature too high
•Soft start for fuse protection
•“switch-on blocking “ at opened amplifier
1.2.3. Features
The manufacturer implemented some of the company’s newest development results with most
wanted operating and safety features into this new model:
•High level of protection
•Memory for faults and warnings, easy maintenance
•Automatic set-up anode current (BIAS) – no need to adjust manually after changing the
tube
•Three programmable working modes of the centrifugal blower ( turbine ) + axial blower
•Full QSK with silent relay
•Many operational parameters to display
•Easy transport due to detachable HV transformer
•The smallest and lightest 2000 W Power Amplifier on the market
1.2.4. The Advantages of OM2000A+
•Full compatibility with: ICOM, ELECRAFT, KENWOOD, TEN-TEC ORION, YAESU,
Icom transceive protocol using by MicroHAM devices ( CI-V output ), FLEX Radios
and Anan
•RF sensitive Band and Frequency switching, for use with radios which do not
have CAT. We recommend using CAT and BAND DATA information due to the
much faster band changing whenever possible.
•Automatic switching between bands. Automatic tuning within the band according to
segments.
•Automatic switching of Band Pass Filter – BAND DATA output compatible with YAESU
radios (BCD code).
•Automatic switching of Antenna switches. The maximum number of antennas is 10,
controlled by BCD output code.
•Remote control via available PC Application.
•http://www.om-power.com/download/HF PA_Manager_

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2. SAFETY INSTRUCTIONS
DANGEROUS HIGH VOLTAGE INSIDE!
The power amplifier is using high voltage up to 3200V DC, which is very dangerous for human
life! Read next safety instructions carefully first, before you will start to install and operate
power amplifier! NEVER VIOLATE THE FOLLOWING SAFETY RULES!
NEVER ALLOW CHILDREN to play around PA or to touch power amplifier or connected cables
in working condition, or to push anything into the case holes!
Never turn the amplifier on without the upper lid in place. DO NOT ATTEMPT TO SHORT OR
BYPASS safety switch under upper lid!
The OM2000A+ amplifier should not be used in a WET or HUMID environment or be exposed to
RAINFALL!
Do not turn the amplifier ON without having connected the ANTENNA or properly rated DUMMY
LOAD! A hazardous HF voltage may build up on the antenna connector after turning the
amplifier on with no antenna or dummy load connected!
Before removing the upper lid of the amplifier make sure that power supply has been
disconnected AT LEAST 10 minutes allowing for the electrolytic capacitors to discharge fully.
Disconnect power cord from the outlet!
Any work inside the PA (internal fuses replacement, tube replacement, etc.) should be carried
out only by aprofessionally qualified person!

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CAUTION
The amplifier must be installed in such a way that free flow of hot air from the tube is allowed.
The amplifier must not be installed in a constrained surrounding (i.e. tight shelves etc.). During
extended operation the tube ventilation grid can reach high temperature. Do not touch it!
The amplifier must be properly grounded during operation.
During operation the amplifier must be installed in such a way that the rear side remains
accessible.
The amplifier is an A category product. In a household it can influence other electric appliances.
In such cases the user is to take proper actions to mitigate this disturbance.
Read this manual carefully. Fallow all of instructions during installation and operation to avoid
damage to the amplifier not covered by manufacturer´s warranty! Do not attempt to perform
any change of hardware or software!
3. GENERAL DESCRIPTION
3.1. HF Compartment
his amplifier is using a ceramic tetrode FU-728F in a grounded-cathode circuit (input into
control grids). The OM2000A+ amplifier achieves excellent linearity by the voltage stabilization of
the control grid bias and the screen voltage. The power input is fed to the control grids, using a
broadband input circuit with an input impedance of 50 Ohms. This adaptable input circuitry
ensures a good input SWR (better than 1.5 : 1) on all amateur bands.
The output of the amplifier is a Pi-L circuit. The ceramic capacitors for TUNE and LOAD are seperate.
This enables the amplifier to be tuned exactly and makes it possible to easily return to the previously
set positions after band changes.
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Top view on the opened OM2000A+
Tetrode FU728F Blower Power Supply Board Switch-ON Board
Output Pi-L Circuit Tuning Capacitor Front Subpanel HV
transformer
3.2. Power Supply
This Power amplifier uses one 3 KVA toroidal transformer. A soft start is provided using relays and
resistors (placed on the switch-ON board). The high voltage is made by combining 4 x 575V AC (total

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abt. 3200V DC) @ 1.2A. Each has its own rectifier and filter. In the high voltage circuit, safety resistors
are employed to protect the amplifier against overload (placed on the power supply board).
The separate screen grid supply is regulated and stabilized with MOSFET circuits and delivers abt.
330V DC at 100mA. Control grid voltage is also stabilized (-120V DC). Change of stabilized first grid
voltage is controlled by the software (EBS for example).
The transformer primary is Tap adjustable for 220, 230, 240 V AC, 50 Hz. The factory setting is
230 VAC (230, 240, 250V AC, 60 Hz for US models, factory setting is 240 V AC.
If the AC voltage in your network is 220 or 240 Volts (230 or 250 Volts for US models), you
need to set the correct transformer tap before first starting the PA. See part 7.1.for more information.
Other primary voltage is possible on request (for example 200V 50/60 Hz for Japan).
3.3. Safety Devices
Control and monitoring circuits ensure control and safety during malfunctions of the PA. These are
placed on the Control board, which is located on the chassis subpanel.
One of the important safety elements is a mechanical
switch for AC blocking an opened amplifier.
4. INSTALLATION
Read this chapter carefully prior to starting installation. Before unpacking inspect shipping
carton for any damage. Keep all of packing parts for possible future shipment. Check
unpacked power amplifier. If you find any damage, contact your dealer immediately to keep
full warranty.
Type of supported TCVR and working
frequency are visible on the display.
AUTO LED is ON.

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4.1. Grounding
The amplifier has to be grounded properly! Connect the screw on the rear panel of the
amplifier to your local grounding system with a copper cable; use a cross-section of 4
mm2 at least.
Connect your transceiver to the same grounding system of your shack carefully! Use minimum length
cables and make certain that the connections are both physically and electrically sound. With poor
grounding, you may risk damaging your equipment, have problems with TVI/BCI or possible distortion
of your transmitted signal.
4.2. Coaxial Cable
The output of the transceiver is to be connected to the input of the amplifier via RG58 or similar 50
Ohm cable. For the connection between the power amplifier and the antenna, RG213 or similar coaxial
cable suited for high power is recommended. SO-239 sockets with Teflon insulation are used for the
HF INPUT and OUTPUT connectors.
Rier view of the amplifier OM2000A+
Fuses Mains Plug HF Output
Blower Grounding point Control HF Input

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4.3. Control Cable
Control cable maintains TX / RX switching of the PA (TX GND). The cable is shielded. On the side of
the power amplifier a CINCH-socket is used. On the side of your transceiver you have to use a socket
suitable for this transceiver. During transmitting the middle pin is connected to the ground. The relays of
the OM2000A+ have to be switched earlier than HF is applied (cold switching). Modern transceivers
they have a time delay between PTT switching and power output.
If you are using an older transceiver or transmitters without time delay, we recommend
to connect the PA in such a way that the transmit/receive switch (foot switch for
example) is connected with the KEY IN socket of the amplifier. The KEY OUT socket is to
be connected with the PTT socket at the transceiver. If there is possible to adjust TX delay in
your TCVR, set the delay to 10ms, please.
The amplifier is equipped with safety devices, which ensure that the output relay is not switched under
power mistakenly (hot switching).
KEY IN RCA Phono - Input signal PTT switching voltage / current -5V /2mA)
KEY OUT RCA Phono - Output signal PTT (maximum switching of 30V / 50mA)
See section 7.9. for Control and ANT/BPF connector PIN-OUT.
Be sure that your power system is correctly wired and properly rated! To use an
adequately sized and connected grounding system is also very important!
4.4. Cooling
The amplifier must be installed in such a way that free flow of hot air from the tube is
allowed. Do not obstruct air intake and exhaust areas of the PA.
The centrifugal blower provides the necessary cooling of the amplifier, even during long contests. The
blower is activated by switching the PA on and it is turned off when cooling is finished (approx. 1-5 min
after switching off the PA depending on the temperature of the tube). Blower working mode is
programmable (3 modes). See page 20 for more details.

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5. OPERATION
Before switching PA on, make sure that amplifier is grounded, antenna or dummy load
is connected, and line cord is plugged into the outlet. Be sure you have selected the
proper AC input TAP (Sect 7.1)
Do not turn PA on for at least 2 hours after unpacking and located in its operating
location. Especially when amplifier is moved from a cold place to a warm one as
condensation may develop. This condition could result in damage to the high voltage
circuits.
We do not recommend changing antennas during a transmission. (Hot switching)
When you decide to have a short operating break, we recommend placing the amplifier to the
standby mode rather than switch it off.
5.1. OM2000A+ Front Panel
Front panel of the OM2000A+ is almost empty…Containing only the touch TFT display plus two control
switches.
ON -Main Switch. After turning ON, a small 12V APU for logic, protection circuits and the display
will be activated. High voltage and RF circuits are still OFF.

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OPR/STBY -Short press for switching betwen STBY and OPERATION mode.
ON/OFF -Long press (1 sec.) for switching the PA ON (tube heating first), 2 seconds for PA
OFF. Always use the ON/OFF button as this allows for a predetermined (software controlled) time to
cool down the tube and inside the PA compartment.
5.2. OM2000A+ control
Turn ON the green Main Power switch and the home screen will lights up. Initial control touch buttons
are visible on the bottom line.
Remember that the home touch screen is active for some information and control settings, while the PA
is still OFF!
BAND
Touch the left side of BAND button to go down, touch the right site to go up. The band information is
displayed above the button.
ANTENNA
Transmitting antenna choice. Functional ONLY when the antenna switch is programmed and antennas
are defined (see page 16). This antenna feature allows switching between antennas authorized for the
current band. An external antenna switch is controlled by BCD code at the ANT/BPF output (see
Section 7.9).

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INFO
Information display shows basic
information about the PA: serial number,
software version, time ON, tube serial
number and nominal Main voltage.
The information screen also provides an
overview of the last 20 warnings and
faults:
Press FAULTS.
Press EXIT to go back to the home
screen.
Now press SETTINGS. This display
shows various menu settings for CAT, NO
CAT, ANTENNA, DISPLAY, EBS, CLEAR
user settings for one or all bands,
BLOWER mode and other INFO.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.

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Screen shows settings possibilities for
CAT, ANTENNA, DISPLAY, NETWORK
SETTING, EBS, BLOWER and other
INFO.
Scroll to CAT SETTINGS (up or down
press SET.
Scroll to your TCVR family (up or down)
select appropriate bit rate (left or right)
then press SET.
Or select NO CAT and press SET.
We recommend using the CAT connection whenever possible because, in such a case, the OM2000A+
has permanent information about the transmit frequency and is immediately ready for transmitting.
With a setting of NO CAT the OM2000A+ detects transmit frequency from the input signal. With the
input signal frequency changing the PA automatically reacts and tunes itself to optimal output
parameters. If NO CAT is used, we recommend using BAND DATA (BCD) information for much faster
band changing.
If you choose YAESU or ICOM NEW,
after SET pressing you will go to deeper
level which allows you to select specific
type of TCVR.ee the following picture for
ICOM NEW selection, for example.
m
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.

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You selected IC7800 addr.6AH and 19200
Bd. Press SET to write to the memory,
then press EXIT to go back to the
SETTINGS possibilities.
“SET OTHER ADDRESS” means that you
must add here a new type of ICOM TCVR
which is not defined in the table (its
address plus bitrate in Bd) to allow
communications with it.
Press ANTENNA SETTINGS. First select
ANTENNA SWITCH (No switch,
Standard). Use left or right arrows. If you
select some switch, 10 ports for different
antennas displays. Generally all of
antennas are allowed in every band
(green squares). To disable some square
select port (up/down), touch SET for
antenna name and then select band
(left/right). Press SET.
.
Four types of antennas for four different
bands were disabled.
Black square means disabled
combination.
Press EXIT to go back to SETTINGS
menu
BCD code (4 bits) is used for automatic antenna and BPF switching (see Antenna/BPF
connector on the Control panel (rear side of the PA). See section 7.9 for Control and ANT/BPF
connectors pin-out.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.

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Next SETTINGS position is for display
parameters. First choose the background
color. Scroll on it and choose the color
(left/right).
Press SAVE twice, then scroll to OWN
CALL.
Press SET for your call sign edit. The
keyboard displays.
Type your call sign and press ENT.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.

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Use next lines and set brightness and
sound volume (use up/down and
left/right). Confirm with SAVE.
Press NETWORK SETTING and then
press ENTER.
Here the user has the option to set IP
Address, Network mask, Default gateway,
Port number.
User can enable or disable IP parameter
setting via LAN connection.
Type of supported TCVR and working
frequency are visible on the display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the display.
AUTO LED is ON.

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Next lines are for EBS (Electronic Bias
Setting) ON/OFF and for EBS level
selection.
We recommend EBS ON. See next
comment for more details.
Electronic Bias Settings (EBS) is a significant feature of this power amplifier. It automatically allows
lower plate current after pressing the PTT, regardless of whether operating CW or SSB mode, when no
RF signal is present at the input. At the moment an RF signal is applied, the bias will automatically
change to its working value.
EBS level means level of the Input power where EBS starts working. Default EBS value is 0.1 W. We
recommend turning EBS ON. A significant feature of using EBS is PA operating temperature reduction.
NOTE: If you are not using compression in your TCVR, or you are not speaking loud enough, some
syllables can be cut off. In such a case you should turn OFF the EBS.
The next two settings allow deletion of
the manual user settings of the amplifier
tunings for a single band or for all bands.
Settings in all segments will return to the
factory default values (for 50 Ohms).
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.

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In the next line you can define working
mode of the blower. In the first mode
speed depends on the PA temperature
(TEMP), In PTT mode the speed
increases to maximum, and the
ALLWAYS mode means maximum speed
all the time during PA operation
(recommended for DIGI modes).
Press SAVE to write the mode to the
memory.
The INFO settings allows viewing all of the
previous PA INFORMATION screen plus
the addition of one more touch key to
enter the UPGRADE mode.
UPGRADE touch button should ONLY be
used if the EEPROM or firmware files (or
both) will be upgraded. In such a case ask
the dealer or manufacturer for the exact
procedure.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.
Type of supported TCVR and
working
frequency are visible on the
display.
AUTO LED is ON.