OM POWER OM2000A+ User manual

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MADE IN SLOVAKIA
e-mail : [e-mail]
WWW.OM-POWER.COM
OM Power, s.r.o. 93030 Báč 126,
SLOVAKIA
Contact : [phone]
e-mail : om[email protected]
OM2000A+
SHORTWAVE PLUS 50 MHz
POWER AMPLIFIER

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TABLE OF CONTENTS
1. GENERAL INFORMATION ..................................................................... 5
1.1. Introduction …………………………………………………………………. 5
1.2. Specification …………………………………………………………………. 5
1.2.1. Parameters …………………………………………………………………. 5
1.2.2. Protection Circuits …………………………………………………………………. 6
1.2.3. Features …………………………………………………………………. 6
1.2.4. The Advantages of OM2000A+ ………………………………………………… 6
2. SAFETY INSTRUCTIONS …………………………………………………………………. 7
3. GENERAL DESCRIPTION …………………………………………………………………. 8
3.1. HF part …………………………………………………………………. 8
3.2. Power Supply …………………………………………………………………. 10
3.3. Safety Devices …………………………………………………………………. 10
4. INSTALLATION …………………………………………………………………. 10
4.1. Grounding …………………………………………………………………. 11
4.2. Coaxial Cable …………………………………………………………………. 11
4.3. Control Cable …………………………………………………………………. 12
4.4. Cooling …………………………………………………………………. 12
5. OPERATION …………………………………………………………………. 13
5.1. OM2000A+ Front Panel …………………………………………………………………. 13
5.2. OM2000A+ Control ………………………………………………………………… 14
5.3. Preparing for operation ………………………………………………………………… 21
5.4. Operation mode …………………………………………………………………. 28
6. MAINTENANCE …………………………………………………………………. 32
6.1. Indication of Fault Conditions ……………………………………………………… 32
6.2. Fuse Replacement …………………………………………………………………. 34

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6.3. Tube Replacement …………………………………………………………………. 34
6.4. Cleaning …………………………………………………………………. 34
7. APPENDIX …………………………………………………………………. 34
7.1. Primary AC selection …………………………………………………………………. 34
7.2. Removing the HV Transformer …………………………………………………….. 36
7.3. Controlling OM200A+ with FLEX Radio Series 6xxx …………………………. 37
7.4. OM2000A+ Remote Control …………………………………………………………. 39
7.5. Remote Control using own public IP Address .................................... 44
7.5.1. Changing OM2000A+ connection settings ................................ 44
7.5.2. Setting up in the Remote software ............................................. 45
7.5.3. Remote Control without own IP Address, behind a router ....... 46
7.6. OM2000A+ firmware upgrade ……………………………………………………… 47
7.7. Icom connection with OM2000A+ ………………………………………………… 53
7.8. Yaesu plus BPF plus ANT Switch connection with OM2000A+ ………. 54
7.9. Control panel connectors pin-out …………………………………………………… 55
7.10. Block Diagram of the OM2000A+ Power Amplifier ………………………… 59
7.11. Troubleshooting ……………………………………………………………………………. 60
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 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 220V, 230V, 240V, 50/60 Hz or other primary
voltages…. (200V 50/60Hz for Japan, 230, 240, 250V 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 of
next parameters exceed defined values or some unwanted occasion 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 to high
Soft start for fuses 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, that is why the PA is usable also with radios, which doesn´t have CAT. By NO
CAT using we recommend to use BAND DATA information due to the much faster band
changing. Possibility of using BAND DATA information.
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 possibility (remote software as accessory –no extra price) 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
NEXT 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 is neither to be used in a WET or HUMID environment nor to 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 opening the upper lid of the amplifier make sure that power supply has been disconnected AT LEAST 10
minutes allowing the electrolytic capacitors to discharge fully. Disconnect power cord from the outlet!
Any work inside the PA (internal fuses replacement, tube replacement, etc.) can be carried out only by
professionally 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 long time operation
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 part
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 given 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.
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The output of the amplifier is a Pi-L circuit. The ceramic capacitor for TUNE and LOAD are divided. This enables
the amplifier to be tuned exactly and makes it possible to easily return to the previously set positions after band
changes.
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

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3.2. Power Supply
Power amplifier is using 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 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 separated supply for screen grid is regulated by stabilization with MOSFET 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).
Primary section of the transformer is adjustable for 220 - 240 VAC (230 –250VAC for US). Factory setting
is 230VAC. If the AC voltage in your network is 220 or 240 Volts, you need to set the correct value before
first starting of 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 element is mechanical switch
for AC blocking at opened amplifier.
4. INSTALLATION
Read this chapter carefully prior you will start installation. Before unpacking inspect shipping carton
first, if it is not damaged. Keep all of packing parts for possible future shipment. Check unpacked power
amplifier. If you find some damaging, contact your dealer immediately to keep full warranty.
During installation go step by step according to the next parts.
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, having problems with TVI/BCI or your transmitted signal may be distorted.
4.2. Coaxial Cable
The output of the transceiver is to be connected to the input of the amplifier via RG58 or similar cable. For the
connection between the power amplifier and the antenna, RG213 or similar coaxial cable suited for high power
is recommended. At the INPUT and OUTPUT SO-239 sockets with Teflon insulation are used.
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 7.6. for Control and ANT/BPF connectors PIN-OUT.
Be sure that your power system is correctly wired and properly rated! To use 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
19 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 putted to the outlet. Be sure you selected AC input by 7.1.
Do not turn PA on for at least 2 hours after unpacking it and locating in its operating location. Especially
when amplifier is moved from a cold place to a warm one because not visible condensation may
develop, and this could result in damage to the high voltage circuits.
We do not recommend to take antenna off during a transmission.
When you decide to have a short operating break, place the amplifier to the standby mode rather than
switch it off.
5.1. OM2000A+ Front Panel
Front panel of the OM2000A is almost empty…There is only touch TFT display accessible plus two switches.
ON - Main Switch. After turning ON 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. Do NOT
use the green button for switching the PA OFF as first! Every time use ON/OFF button as first to give chance for
cooling the tube and inside area of the PA.
5.2. OM2000A+ control
Turn ON the Main switch and the home screen will lights up. In the bottom line touch buttons are visible
Remember that the home screen is active for some information and settings , while PA is still OFF!
BAND
Touch the left side of BAND button to go down, touch the right site to go up with band displayed above the
button.
ANTENNA
Transmitting antenna choice. Functional ONLY when the antenna switch is programmed and antennas are defined
(see next parts). It allows switching between antennas authorized for the current band. An external antenna
switch is controlled by BCD code at the ANT/BPF output.
INFO
Information display shows basic information about the PA: serial number, software version, time ON, tube serial
number and nominal Main voltage. Some of them manufacturer can requested in case of any failure, etc.

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Also it provides an overview of the last 20
warnings and faults:
Touch FAULTS.
Press EXIT to go back to the home screen.
Now press SETTINGS. Display shows menu
which allows to set CAT, NO CAT, ANTENNA,
DISPLAY, EBS, CLEAR user settings for one or all
bands, BLOWER mode and another 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 infos.
Scroll to CAT SETTINGS (up or down) and touch
SET.
Scroll to your TCVR family (up or down) and
select bit rate (left or right), then press SET.
Or select NO CAT and press SET.
We recommend to use CAT connection always when possible, because in such a case OM2000A+ has permanent
information about the transmit frequency and is immediately ready for transmitting.
With setting NO CAT the OM2000A+ detects transmit frequency from the input signal. With the input signal
frequency changing the PA automatically reacts and tune itself to optimal output parameters. Tuning takes abt.
1sec. inside the band, abt. 2 sec if band is changed. By NO CAT using we recommend to use BAND DATA
information due to the 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. See
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 used ICOM TCVR which
is not defined in the table (its address plus
bitrate in Bd) to have possibility to
communicate with it.
Touch 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). Touch
SET.
Four types of antenna for four different bands
were disabled.
Black square means disabled combination.
Press EXIT to go back to SETTINGS menu.
BCD code (4 bits) is using for automatic antenna and BPF switching (see Antenna/BPF connector on the
Control panel (rear side of the PA). See section 7.8. 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 callsign edit. The keyboard
displays.
Type your callsign 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 have possibility 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 one of significant feature of the power amplifier. It allows to set low plate current
after pressing the PTT regardless of whether you have CW or SSB mode, until RF signal is no present at the input.
At the moment when RF signal comes to the input of PA, 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
using EBS ON. Significant accompaniment of used EBS is temperature reducing.
If you are not using compressor in your TCVR or you are speaking not good enough loud, some syllables can be
cutted off. In such a case you have possibility to turn OFF the EBS.
level means level of the Input power,
Next two lines allow delete user settings of
antenna tunings for selected 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.

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In the next line you can define working mode
of the blower. In the first case speed depends
on the temperature (TEMP), during PTT speed
increased to maximum, ALLWAYS means
maximum speed all the time during PA
operation (recommended for DIGI modes).
Press SAVE to write the mode to the memory.
Last settings allows to see INFO. All of previous
information screen will be visible plus one
more for upgrade.
UPGRADE touch button can be used ONLY in
the case if EEPROM or firmware files (or both)
will be upgraded. In such a case ask 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.