1. Introducció
The MFJ-828 is a versatile Digital SWR/Wattmeter and Frequency Counter designed for amateur radio and RF applications. It provides accurate measurements of Forward Power, Reflected Power, SWR, and Frequency across a wide range from 1.8 MHz to 54 MHz, handling power levels up to 1500 Watts. This manual provides essential information for the proper setup, operation, and maintenance of your MFJ-828 unit.
2. Informació de seguretat
Please read and understand all safety instructions before operating the MFJ-828. Failure to do so may result in damage to the unit, other equipment, or personal injury.
- Font d'alimentació: Ensure the correct DC power supply (not included) is used. Incorrect voltagLa polaritat o el voltatge poden danyar la unitat.
- Exposició a RF: Always observe proper RF safety guidelines when transmitting. High RF power can cause burns or other injuries.
- Ventilació: No bloquegeu les obertures de ventilació. Assegureu-vos que hi hagi un flux d'aire adequat al voltant de la unitat per evitar el sobreescalfament.
- Medi ambient: Operate the unit in a dry environment, away from moisture, extreme temperatures, and direct sunlight.
- Manteniment: Demaneu totes les tasques de manteniment a personal qualificat. No intenteu obrir ni reparar la unitat vosaltres mateixos.
3. Contingut del paquet
Carefully unpack your MFJ-828 and verify that all items are present and undamaged. If any items are missing or damaged, contact your dealer immediately.
- MFJ-828 Digital SWR/Wattmeter/Frequency Counter Unit
- Manual d'usuari (aquest document)
- Note: A 12V DC power supply is required for operation and is typically sold separately.
4. Configuració
Follow these steps to set up your MFJ-828 for operation:
- Col·locació: Place the MFJ-828 on a stable, flat surface, ensuring adequate ventilation around the unit.
- Connexió d'antena: Connect your antenna system to the "ANTENNA" (or "OUTPUT") SO-239 connector on the rear panel of the MFJ-828.
- Connexió del transceptor: Connect your transceiver's RF output to the "TRANSCEIVER" (or "INPUT") SO-239 connector on the rear panel of the MFJ-828. Use high-quality coaxial cables with appropriate connectors.
- Connexió d'alimentació: Connect a suitable 12V DC power supply (not included) to the DC input jack on the rear panel. Ensure correct polarity. The unit requires a stable 12V DC supply.
- Encesa inicial: Premeu el botó PODER button on the front panel to turn on the unit. The digital display should illuminate.
Figura 4.1: Frontal view of the MFJ-828 Digital SWR/Wattmeter/Frequency Counter, showing the analog SWR/Wattmeter display on the left and the digital LCD display on the right. The digital display shows frequency, forward power (FWD), and reflected power (REF) readings. Below the digital display are buttons for MODE, PEAK, and ALARM, and a POWER button.
5. Instruccions de funcionament
The MFJ-828 provides both analog and digital readouts for SWR, power, and frequency.
5.1. Encendre/apagar
- Per encendre la unitat, premeu el botó PODER botó.
- Per apagar la unitat, premeu el botó PODER botó de nou.
5.2. Reading SWR and Power
The MFJ-828 displays SWR and power on both the analog meter and the digital LCD.
- Mesurador analògic: The large analog meter on the left provides a quick visual indication of Forward Power (Watts) and SWR. The SWR scale is typically located at the bottom of the meter.
- Pantalla digital: The LCD on the right provides precise digital readings.
- Freqüència: Displays the operating frequency in MHz.
- FWD (Forward Power): Shows the forward power in Watts.
- REF (Reflected Power): Shows the reflected power in Watts.
- SWR: Displays the Standing Wave Ratio numerically.
5.3. Botó MODE
El MODE button cycles through different display modes or measurement parameters on the digital screen. Consult the specific mode functions by pressing the button and observing the display changes.
5.4. PEAK Button
El PIC button (often labeled "PEAK ▲") is used to activate or reset the peak hold function for power readings. When active, the display will hold the highest power reading detected until reset or a higher peak is measured. This is particularly useful for CW (Morse Code) or SSB (Single Sideband) transmissions to capture peak power.
5.5. Botó ALARMA
El ALARMA button (often labeled "ALARM ▼") is used to set or clear SWR or power alarms. When an alarm is set, the unit may beep or display an error message if SWR or power exceeds a predefined threshold. Refer to the manufacturer's detailed instructions for setting alarm thresholds.
6. Manteniment
Proper maintenance ensures the longevity and accuracy of your MFJ-828.
- Neteja: Feu servir un drap suau i sec per netejar l'exterior de la unitat. No utilitzeu productes de neteja abrasius ni dissolvents.
- Emmagatzematge: Quan no l'utilitzeu durant períodes prolongats, guardeu la unitat en un lloc fresc i sec, allunyat de la llum solar directa i de temperatures extremes.
- Connexions: Periodically check all coaxial and power connections to ensure they are secure and free from corrosion.
7. Solució De Problemes
If you encounter issues with your MFJ-828, refer to the following common problems and solutions:
| Problema | Causa possible | Solució |
|---|---|---|
| La unitat no s'encén. | No power supply connected, incorrect power supply, faulty power cable, unit not switched on. | Ensure 12V DC power supply is connected and functional. Check power cable. Press the POWER button. |
| Incorrect SWR/Power readings. | Loose coaxial connections, faulty cables, incorrect power range selected (if applicable), unit malfunction. | Check all RF connections. Test with known good cables. Ensure proper operation of transceiver and antenna. |
| Frequency counter erratic (e.g., during CW). | Nature of CW signal (pulsed), internal processing limitations. | This behavior may be inherent to the design for certain signal types. Focus on average readings or use for continuous signals. |
| "Oops error" or beeping at high power. | Exceeding the maximum power handling capacity (1500W). | Reduce transmit power. The unit is designed for a maximum of 1500 Watts. |
If the problem persists after attempting these solutions, contact MFJ customer support or your dealer for further assistance.
8. Especificacions
| Característica | Detall |
|---|---|
| Model | MFJ-828 |
| Interval de freqüència | 1.8 a 54 MHz |
| Maneig de potència màxima | 1500 watts |
| Tipus de visualització | Analog Meter and Digital LCD |
| Entrada de potència | 12V CC (font d'alimentació no inclosa) |
| Connectors | SO-239 (UHF femella) |
| Dimensions (aprox.) | 14 x 10 x 5 polzades (dimensions del paquet) |
| Pes (aprox.) | 6.61 lliures |
| Color | Negre |
9. Garantia i Suport
MFJ Enterprises, Inc. products are typically covered by a limited warranty. For specific warranty terms and conditions, please refer to the warranty card included with your product or visit the official MFJ website. For technical support, service, or parts, please contact MFJ customer service directly. Have your model number (MFJ-828) and purchase information ready when contacting support.
Contact information can usually be found on the manufacturer's weblloc web o a l'embalatge del producte.
