OM POWER OM2000A+ User manual

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MADE IN SLOVAKIA
OM Power, s.r.o. 93030 Báč126,
SLOVAKIA
Contact : [phone]
e-mail: [e-mail]
WWW.OM-POWER.COM
Instruction Manual
OM2000A+
SHORTWAVE PLUS 50 MHz
POWER AMPLIFIER
FCC ID: X8NOM2000A
+

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Thank you for purchasing this new model of the OM Power’s RF power amplifiers line for HF and 50
MHz amateur radio bands. You now own, the OM2000A+, an automatic unit with no knobs, no rotary
switches on the front panel, just two small switches and one large touch display.
Smart design, modern conception, high reliability is the result of OM Power’s development and many
years of experience with overall solutions and special attention with the design of the protection circuits.
This product is covered by two years of warranty on the amplifier itself and one year for the tube.
We wish you will have many years of trouble-free use of this equipment, lots of fun and successful
contacts in the world of amateur radio.
The Array Solutions and
OM Power Team

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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
6.3. Tube Replacement ………………………………………………..…. 34

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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

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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 1500+ W in SSB/CW on HF bands, 1500 W in CW/SSB on 6m
1500 W in RTTY
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)
Transformers One toroidal transformer 3kVA
Dimensions 390 x 195 x 370 (width x height x depth)
Weight 24 kg (53 lb)
T

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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. The PA is usable also with radios, which doesn´t have CAT (automatic
frequency reading even if no CAT). 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.
T

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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 230 - 250 VAC. Factory setting is 240VAC.
If the AC voltage in your network is 230 or 250 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.
Type of supported TCVR and working
frequency are visible on the display.
AUTO LED is ON.

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During installation go step by step according to the next parts.
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(AWG 12 ) 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.
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 change antenna output 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.
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.

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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,
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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Scroll to CAT SETTINGS (up or down)
and touch SET.
Scroll to your TCVR family (up or down)
and select baud 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.
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.
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 bit rate 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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NETWORK SETTINGS is present in
software version 4.01 and above (all
software software releases after May
2017 already includes this feature)
Press SET to enter to this settings.
In the NETWORK SETTINGS submenu
you can adjust all needed parameters for
LAN or WAN connection.
Set IP settings throught LAN to ON when
you want to change this parameter trought
LAN. (see page 44)
Press SAVE to write the changes to the
memory.
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.
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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Press SET for your callsign edit. The
keyboard displays.
Type your callsign and press ENT.
Use next lines and set brightness and
sound volume (use up/down and
left/right). Confirm with SAVE.
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
Settting) 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.
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).
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.
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.