………………………………………………………. 1.2. Specification ………………………………………………………. 1.2.1. Parameters ………………………………………………. 1.2.2. Protection Circuits ………………………………………………. 1.2.3. Features ………………………………………………………. 1.2.4. The Advantages of OM2501A …………………………………… 2. SAFETY INSTRUCTIONS ………………………………………………. 3. GENERAL DESCRIPTION ………………………………………………. 3.1. HF Compartment …………………………………………………………. 3.2. Power Supply …………………………………………………………. 3.3. Safety Devices ………………………………………………………….
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7.4.3. Remote Control without own IP Address, behind a router ..7.5. OM2501A firmware upgrade …………………………..………… 7.6. Icom connection with OM2501A ……………………………….… 7.7. Yaesu plus BPF plus ANT Switch connection with OM2501A … 7.8. Control panel connectors pin-out …………………………….…… 7.9. Block Diagram of the OM2501A Power Amplifier …………..… 7.10.
OM Power model OM2501A and OM3501A are designed for all short wave amateur bands from 1.8 to 29.7 MHz (including WARC bands) and all modes. OM2501A is equipped with a FU- 728F or GU84B ceramic tetrode and OM3501A is with GU78b ceramic tetrode.
• Easy transport due to detachable HV transformer • 1.2.4. The Advantages of OM2501A • 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 •...
Never turn the amplifier on without the upper lid in place. DO NOT ATTEMPT TO SHORT OR BYPASS safety switch under upper lid! The OM2501A amplifier should not be used in a WET or HUMID environment or be exposed to RAINFALL!
(input into control grids). The OM2501A (OM3501A) 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.
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The output of the amplifier is a Pi-L circuit. The variable capacitors for TUNE and LOAD are separate. 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 OM2501A Tetrode FU728F Blower...
3.2. Power Supply This Power amplifier uses two 2 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 8 x 410 V (total 3280V) @ 2,0 A . 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).
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 OM2501A Mains Plugs Fuses...
During transmitting the middle pin is connected to the ground. The relays of the OM2501A have to be switched earlier than HF is applied (cold switching). Modern transceivers they have a time delay between PTT switching and power output.
5.1. OM2501A Front Panel Front panel of the OM2501A (OM3501A) is almost empty…Containing only the touch TFT display plus two control switches. Main Switch. After turning ON, a small 12V APU for logic, protection circuits and the display will be activated.
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. OM2501A 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.
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The information screen also provides an Type of supported TCVR and overview of the last 20 warnings and working faults: frequency are visible on the display. Press FAULTS. AUTO LED is ON. Type of supported TCVR and working frequency are visible on the Press EXIT to go back to the home display.
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With a setting of NO CAT the OM2501A (OM3501A) detects transmit frequency from the input signal. With the input signal frequency changing the PA automatically reacts and tunes itself to optimal output parameters..
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You selected IC7800 addr.6AH and 19200 Bd. Press SET to write to the Type of supported TCVR and memory, then press EXIT to go back to working the SETTINGS possibilities. “SET OTHER ADDRESS” means that frequency are visible on the display.
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Next SETTINGS position is for display Type of supported TCVR and parameters. First choose the background working color. Scroll on it and choose the color (left/right). frequency are visible on the display. Press SAVE twice, then scroll to OWN CALL. AUTO LED is ON.
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Type of supported TCVR and Press NETWORK SETTING and then working press ENTER. frequency are visible on the display. AUTO LED is ON. Here the user has the option to set IP Address, Network mask, Default Type of supported TCVR and gateway, Port number.
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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.
It will take 180 seconds. Turning PA ON is possible ONLY from the home screen! If you have other display active, press EXIT more times to go back to the home screen. (These same functions are also available on the OM Power Remote Control PC Application)
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Type of supported TCVR and The “Tube Heating Timer” is visible working on the display. Wait until the required 180 seconds is complete before frequency are visible on the display. placing the amplifier in OPERATE Mode. AUTO LED is ON. After heating is completed, the PA will Type of supported TCVR and working light the STBY mode indicator and this...
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The Menu display allows the user to go Type of supported TCVR and working deeper into SETTINGS mode, MEASuring mode or SERVICE mode. frequency are visible on the display. AUTO LED is ON. Type of supported TCVR and working Press SETTING button. frequency are visible on the display.
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Type in the actual setting of the primary Type of supported TCVR and working voltage tap and press ENT. frequency are visible on the display. Press EXIT twice to go back to the Menu display. AUTO LED is ON. This is the actual physical setting of the primary voltage tap. It is just information for the processor, which protects the permitted limits ( up or down) for a given value of the primary voltage (protection circuit).
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NOTE: Follow these steps to populate BARG2 and BARG3 as desired. Type of supported TCVR and working Press EXIT to go back to the Menu display, frequency are visible on the display. then press SERVICE. AUTO LED is ON. Now we are in the SERVICE settings mode. Type of supported TCVR and working Scroll to selected line and press SHOW or frequency are visible on the display.
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You can try to do this manually, too. Type of supported TCVR and working Scroll to SET EBS1 MANUAL and press frequency are visible on the display. SET. Use up/down buttons to set 20mA or as close as possible value and press SAVE. AUTO LED is ON.
5.4. Operation mode Before switching to operation mode, check all connections between PA and TCVR. We are now back in the Main display, bar graphs defined, antennas preprogrammed, Type of supported TCVR and working CAT was set. We are ready to go to the operation mode.
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We also have a new M-TUNE button here. M-TUNE means entry into the manual tuning mode. It allows fine tuning of the PA, especially in cases where the antenna impedance is different from real 50 Ohms. For proper adjustment we need to show Screen current (at least).
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These parameters were SAVED. AUTO LED is ON. NOTE: The OM2501A is factory adjusted to a maximum output power of 2500W into a 50 Ohm load. A unique Tuning table, with TUNE and LOAD values for every band, is supplied with each PA.
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Press PTT, check the Ig2 (I Screen on the display). If it is ok (bellow +20mA), gradually • increase the input power until the PA reaches about 70% of its maximum output power. Using the TUNE buttons, adjust for maximum FORWARD POWER while monitoring the •...
6.1. Indication of Fault Conditions If a fault condition appears during the operation of the amplifier, the safety circuits of OM2501A will react immediately. There are several types of warning or fault messages that may appear on the display when any of the protection circuits are activated. The OM2501A power amplifier provides the...
AUTO LED is ON. Never try to change or move any part inside the amplifier except the tube or fuses. Substitution of parts may void intrinsic safety! Manufacturer’s contacts: OM POWER, s.r.o. 930 30 Báč 126 SLOVAKIA Email: om-power@om-power.co 6.2.
One special fuse, filled with sand, is used in the model OM2501A. In the case of an accidental discharges or short within the tube this fuse (4 Amps fast, filled with sand) saves the HV supply circuits. Type of supported TCVR and working frequency are visible on the display.
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Side view on the opened OM2501A (OM3501A) HV supply board AC Selector SW ON board HV Transformers Remove the upper lid first. On the right side of the PA, there are two PCBs mounted. On the right upper side is Switch ON board where AC selector is located.
It must be an existing serial port – a hardware COM port in your PC or an USB to serial port adapter. Connect the chosen COM port and the transceiver port ( TCVR DB9 )to the OM Power amplifier with a null modem serial cable (both ends of the cable have a female DB-9 connector and pins 2 and 3 are crossed).
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Flex Radio 6xxx series connection using USB output AUTO LED is ON. Connect from the Flex USB port directly to the TCVR port on the OM2501A using an USB – FTDI port adapter and serial a null modem serial cable (both ends of the cable have a female DB-9 connectors (pins 2 and 3 are crossed).
Check that ENABLED is selected in both associated USB windows. Close both windows. The OM2501A will now follow the Band and Frequency changes on the Flex 6XXX. 7.3. OM2501A (OM3501A) Remote Control The OM Power team has developed special software which allows controlling the PA OM2501A remotely.
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Connection setting: Set up TCP/IP address and port: Connect / disconnect to OM2501A:...
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View last 20 PA faults: Anennas Settings: Screen selections: Minimal view: NOTE: To return to the normal view from the minimal view just right click with your mouse...
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Normal view: Advanced view: Fine tune screen: It is possible to retune the PA TUNE and LOAD remotely (See page 31).
7.4. Remote Control using own public IP address: 7.4.1 Changing OM2501A connection settings Connect the LAN connector on the OM2501A to your local Internet with ethernet cable. Open up a WEB browser and enter the OM2501A current IP address (default is Type of supported TCVR and working 192.168.1.222????).
If necessary it is also possible to change the OM2501A local Port number. Make any changes as required in the Connection menu. When finished, click OK. When completely finished, click Apply Settings in the main Menu. 7.4.2 Setting up in the Remote software...
Open Firewall Settings (depends on router software, can be called Forwarding, Port Forwarding, or something similar). As Server IP enter the OM2501A IP Address, 192.168.1.222 if you haven't changed it, or the one you changed to in point 7.5.1. Private port should be 10001 in default, or the one you changed to in point 7.5.1.
Download the firmware upgrade software and latest firmware file for the OM2501A (OM3501A) from the official OM Power website http://www.om-power.com/downloads. Store it to OM2501A folder created on your PC. NOTE: Use a serial null modem cable and connect the TCVR port on the OM2501A rear panel with a COM port on the PC.
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Open folder OM2501A on your PC, find the MX460L.exe file and run it. Type of supported TCVR and working frequency are visible on the display. AUTO LED is ON. Select SETTINGS and choose the COM port you want to use. Baud rate should be 115200.
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Switch ON the power amplifier using the front panel green ON switch. Press SETTINGS to enter the SETTINGS Type of supported TCVR and Menu. working frequency are visible on the display. AUTO LED is ON. Choose INFO and press SHOW. Type of supported TCVR and working frequency are visible on the...
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At the end you will return to the main screen of OM2501A. Switch PA OFF, disconnect the TCVR serial cable and you are ready to use the OM2501A with the new firmware. AUTO LED is ON.
7.8. Control panel (rear side) connectors pin-out TCVR connector DB 9 male RS232 connection with TCVR. For CAT communication connect pin 2 RX-D, pin 3 TX-D and pin 5 GROUND CI-V connector Use CI-V connection for communication with ICOM type transceiver. Signal CI-V is connected to the Tip.
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PC connector DB 9 female RS232 connection to the computer. For CAT communication connect pin 2 TX- D, pin 3 RX-D and pin 5 GROUND KEY IN – RCA connector Input signal PTT switching voltage / current 5V /2mA) KEY OUT – RCA connector Output signal PTT (maximum switching of 30V / 50mA) LAN connector Use for connection to the LAN or WAN network.
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CONTROL connector D-sub 15 female - GROUND - KEY OUT - ouput signal PTT ( maximum switching of 30V / 50mA - KEY IN input signal PTT – switching voltage / current 5V / 2mA - CI-V CI-V input for Icom CAT. The same as CI-V jack connector - BAND data A input - input BCD Yaesu compatibile code from TCVR - bit 0 - BAND data B input - input BCD Yaesu compatibile code from TCVR - bit 1 - BAND data C input - input BCD Yaesu compatibile code from TCVR - bit 2...
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(OM3501A) OM2501A can address up to 10 antenna port, see antenna BCD code table below Logic value Antenna port UNDEFINED ANT 1 ANT 2 ANT 3 ANT 4 ANT 5 ANT 6 ANT 7 ANT 8 ANT 9 ANT 10...
7.11 Troubleshooting The OM2501A (OM3501A) power amplifier contains several protection circuits, which constantly monitor operation of the Amplifier. When the firmware defined parameters exceed defined operating levels, a WARNING appears in the LAST EVENTS window of the PA front panel. If some parameters exceed a defined critical level, a FAULT is activated and the PA will automatically switch to STBY mode.
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Factory reset: In the case of very abnormal behavior of the OM2501A it is possible to do a factory reset. This will reset all the amplifier parameters back to the factory default values.
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After the FACTORY RESET completes the PA is ready for operation. Type of supported TCVR and working frequency are visible on the display. AUTO LED is ON. Important notice: Perform a Factory Reset only if absolutely necessary to clear abnormal behavior, because personalized settings, mainly CAT communication with TCVR, antenna switch settings and any USER settings must be re-input.
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