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Summary of Contents for LXQQFY MR300 SWR
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MR300 SWR Analyzer User Manual Revision 171215 This product is revised by SARK100, and the technology is from Melchor Varel(EA4FRB) Revision 171215 MR300 SWR Analyzer...
Connectors: RF Out: M (SL16) USB: Mini-B receptacle External power: 2.1mm Power Jack (center pin positive) Instrument Capabilities: Measure antenna electrical parameters: SWR, impedance (resistance + reactance), capacitance, inductance Measure feed point impedance Revision 171215 MR300 SWR Analyzer...
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Q, resonant frequency, bandwidth, impedance Determine characteristic impedance of transmission line Determine length of ¼ and ½ wave phasing lines Coaxial Cable Loss Determine antenna tuner loss Measure balun loss Measure inductor Q Estimate quartz crystal parameters Revision 171215 MR300 SWR Analyzer...
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The cursor will move to any of the seven available digits, allowing subsequent up/down adjustment of that digit after pressing again the frequency change buttons. A blinking cursor will be display during the digit adjustment mode. Revision 171215 MR300 SWR Analyzer...
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In this mode it is measured the SWR and the complex impedance. An example screen is the following: IMP 14,100.000 1.02 45 + j 50 The top line indicates the mode and the frequency The first number on the second line is the SWR, in this case 1.02:1 Revision 171215 MR300 SWR Analyzer...
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XL 2 pi F L Off Mode In this mode it is disabled the DDS and the impedance measurements.It is provided a RF level measurement mode where the measured signal level is displayed in the second line of the Revision 171215 MR300 SWR Analyzer...
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31,000.000 31,000.000 40,000.000 49,000.000 49,000.000 51,000.000 53,000.000 SCAN Pressing the SCAN pushbutton will automatically sweep the antenna analyzer test signal across the band range previously selected, incrementing from the lower frequency limit to the upper Revision 171215 MR300 SWR Analyzer...
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USB cable. The COM port setting is 57600, 8, n, 1, with no hardware flow control. By entering this function the analyzer will send the following text to the terminal and will display the command prompt: SARK SWR Analyzer V05 >> Revision 171215 MR300 SWR Analyzer...
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This function allows calibrating the instrument in order to get better accuracy. By entering this function the user is instructed to follow a series of steps which are described in detail in the Appendix B: Software Load Don’t update software. Revision 171215 MR300 SWR Analyzer...
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RF output connector and select Capacitance from the Mode pushbutton menu. You can accurately measure capacitance values as long as the reactance at the measurement frequency is within the impedance measurement specifications of the analyzer (about 10 to 2000 Ω). Revision 171215 MR300 SWR Analyzer...
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50 ohm coax has a capacitance of about 29 to 30 pf. For example RG58/U is specified at 28.8 pf per foot so a length of about 3.5 ft – including a 1” pigtail for attachment will serve as a fairly accurate 100 pf capacitor. Revision 171215 MR300 SWR Analyzer...
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Next subtract the exact 51 Ω resistor value from the measured R value and use this new resistance in the above formula to calculate the Q value. Revision 171215 MR300 SWR Analyzer...
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If the measured SWR is above 9:1 that’s good news since the SWR then is less than 1 dB. If you vary the analyzer frequency you will see that SWR decreases with frequency indicating that loss increases at higher frequencies. Revision 171215 MR300 SWR Analyzer...
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Where L is the length in cm, VF is the velocity factor and F is the operating frequency in MHz for the stub. Similarly for a quarter-wave stub use the formula: 7500 V F L Revision 171215 MR300 SWR Analyzer...
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Ideally the line should be dressed along to top of a wooden fence or supported by fiber rope or string. Now tune the MR300 for lowest SWR and note the frequency. VF can now be calculated using the formula: VF Where F is the measured frequency in MHz. Revision 171215 MR300 SWR Analyzer...
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SWR, resistance, reactance, etc.. It also represents Smith chart format. In the following pages there are examples of ZPlots graphs. The complete manual of the original program is available on the project website. Revision 171215 MR300 SWR Analyzer...
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6 Windows software on PC MR300 can also be connected with the Windows application, download from lxqqfy.com. URL: http://www.lxqqfy.com/index/files.php?id=MR300_win 1. Using USB to connect computers and MR300. 2. Click the 'MODE' button on the MR300 to enter the 'PC Link' interface.
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7 App software on Android MR300 also connected via Bluetooth and mobile phone, download from lxqqfy.com. URL: http://www.lxqqfy.com/index/files.php?id=MR300_app Bluetooth connection password: 1234 1. Using USB to connect computers and MR300. 2. Click the 'MODE' button on the MR300 to enter the 'PC Link' interface.
Because of the transportation condition is not allowed, MR300 only provides the battery interface, does not take the battery. Battery Specification: 9.6V nickel hydrogen battery, AAA 800mah. Note: positive and negative pole connection. Step 1: Open shell. Step 2: A total of 4 screws. Revision 171215 MR300 SWR Analyzer...
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Step 3: Choosing the right battery. Step 4: Pay attention to the positive and negative. Revision 171215 MR300 SWR Analyzer...
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COM port with the FTDI driver reference. Please note the COM port name as it will be necessary to know to use the MR300 from your PC, eg for software updates or to control the instrument from HyperTerminal. Revision 171215 MR300 SWR Analyzer...
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6. Once the calibration is finished it will show the text “Done”. This means that the calibration process has been completed and stored in the EEPROM. Just press VAL to continue Revision 171215 MR300 SWR Analyzer...
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Error: freq not set Example >>on Command Description Disables DDS signal generation Arguments Response Error response Example >>off Command freq Description Sets DDS frequency Arguments {frequency} Frequency in Hertz Response Error response Error: invalid freq Example >>freq 14070000 Revision 171215 MR300 SWR Analyzer...
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Command Description Get impedance values Arguments Response {SWR},{R},{X},{Z} Error response Example >>imp 1.05,52,10,51 Command Description Get raw bridge voltages Arguments Response {Vf},{Vr},{Vz},{Va} Error response Example >>raw 257300,165500,31800,214500 Revision 171215 MR300 SWR Analyzer...
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{freq_start} Start freq. in Hz {freq_end} End freq. in Hz {step} Step in Hz Response Start {SWR},{R},{X},{Z} {SWR},{R},{X},{Z} … Error response Error: expected freq val Error: expected step val Example >>scan Start 1.05,52,10,51 1.05,52,10,51 Revision 171215 MR300 SWR Analyzer...
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{freq_start} Start freq. in Hz {freq_end} End freq. in Hz {step} Step in Hz Response Start {Vf},{Vr},{Vz},{Va} {Vf},{Vr},{Vz},{Va} … Error response Error: expected freq val Error: expected step val Example >>scan Start 257300,165500,31800,214500 257300,165500,31800,214500 … Revision 171215 MR300 SWR Analyzer...
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