1. Introduction
The PNI SWR-300 is a compact and reliable SWR and power meter designed for measuring the Standing Wave Ratio (SWR) of radio antennas and the output power of CB radio stations. This manual provides essential information for the correct installation, operation, and maintenance of your device, ensuring optimal performance within the 26-30 MHz frequency range.
2. Safety Information
- Always ensure all cable connections are secure and correct before operating the device.
- Do not expose the device to moisture, rain, or extreme temperatures.
- Avoid dropping or subjecting the device to strong impacts.
- Do not attempt to open the casing or perform repairs yourself. Refer to qualified personnel for service.
- Keep the device away from strong electromagnetic fields.
3. Package Contents
- PNI SWR-300 SWR & Power Meter Unit
- User Manual
4. Setup and Connections
Follow these steps to correctly connect your PNI SWR-300 meter:
- Connect Antenna: Connect your CB radio antenna to the 'ANT' (Antenna) SO-239 connector located on the rear panel of the SWR meter.
- Connect Transceiver: Connect your CB radio transceiver (radio) to the 'TRANS' (Transceiver) SO-239 connector located on the rear panel of the SWR meter.
- Secure Connections: Ensure all coaxial cable connections are tight and secure to prevent signal loss and inaccurate readings.
Figure 4.1: Rear view of PNI SWR-300 showing ANT and TRANS connectors.
5. Operating Instructions
The PNI SWR-300 features an analog meter, power range switches, and a calibration knob. Familiarize yourself with these controls:
Figure 5.1: Front view of PNI SWR-300 controls.
5.1. Measuring SWR (Standing Wave Ratio)
To measure your antenna's SWR, follow these steps:
- Power Range Selection: Set the power range switch (labeled '10W FWD' / '100W REF') to the appropriate range for your radio's output power. Use '10W FWD' for lower power radios (up to 10W) and '100W REF' for higher power radios (up to 100W).
- Mode Selection: Set the 'SWR / PWR' switch to 'SWR'.
- Transmit: Press and hold your radio's transmit (PTT) button to transmit a continuous carrier signal.
- Calibrate: While transmitting, slowly rotate the 'CAL' knob until the meter needle aligns precisely with the 'SET' mark on the meter scale.
- Read SWR: Release the transmit button. The meter now displays the SWR value. A lower SWR (ideally between 1.0 and 1.5) indicates a better-tuned antenna.
- Adjust Antenna: If the SWR is high, adjust your antenna according to its specific instructions to achieve the lowest possible SWR. Repeat the calibration and measurement process after each adjustment.
5.2. Measuring Output Power
To measure your radio's output power, follow these steps:
- Power Range Selection: Set the power range switch ('10W FWD' / '100W REF') to the appropriate range for your radio's expected output power.
- Mode Selection: Set the 'SWR / PWR' switch to 'PWR'.
- Transmit: Press and hold your radio's transmit (PTT) button to transmit a continuous carrier signal.
- Read Power: The meter will directly display your radio's output power in Watts on the 'WATT' scale.
6. Care and Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the device. Do not use abrasive cleaners or solvents.
- Storage: Store the SWR meter in a dry, dust-free environment when not in use.
- Handling: Handle the device with care to avoid damage to the internal components or the meter needle.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No meter reading | Loose or incorrect cable connections. Radio not transmitting. | Check all coaxial cable connections. Ensure the radio is powered on and transmitting. |
| High SWR reading | Poorly tuned antenna. Damaged antenna or cable. | Adjust antenna for optimal tuning. Inspect antenna and cable for physical damage or shorts. |
| Inaccurate readings | Incorrect power range selected. Meter not calibrated for SWR. | Ensure the correct '10W FWD' or '100W REF' range is selected. Always calibrate the meter to 'SET' before reading SWR. |
8. Technical Specifications
- Model: PNI-SWR300
- Frequency Range: 26-30 MHz (for SWR and Power measurement)
- Power Measurement Ranges: 0.5-10 W / 10-100 W
- SWR Accuracy: ± 5%
- Power Accuracy: ± 10%
- Impedance: 50 Ohms
- Connectors: SO-239
- Product Dimensions (L x W x H): 8.5 x 7.6 x 5.8 cm
- Weight: 216 grams
- Compliant Specifications: CE
- Manufacturer: ONLINESHOP SRL
- Country of Origin: China
9. Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the documentation provided at the time of purchase or contact your retailer. You may also visit the official PNI website for further assistance.
