LDG Electronics RT-100 Watt Remote Mount Tuner and RC-100 Control Unit Instruction Manual

1. Introduction

The LDG RT-100 is an automatic antenna tuner designed for remote outdoor installation, typically at or near the antenna feedpoint. This placement is crucial for minimizing Standing Wave Ratio (SWR) losses in the transmission line, thereby improving overall system efficiency. The RT-100 is engineered to handle power levels up to 125 watts for Single Sideband (SSB) and Continuous Wave (CW) modes. Its robust construction features a weatherproof enclosure, making it suitable for various environmental conditions.

Power for the RT-100 is supplied directly over the coaxial cable from the included RC-100 remote controller, which also functions as a Bias-T. The RC-100 allows for convenient control of the tuner from your operating position. The RT-100 incorporates advanced memory tuning capabilities, storing up to 2,000 memory locations. This feature enables nearly instantaneous tuning when operating near previously used frequencies, as the tuner recalls optimal settings. It adapts to your preferred frequencies and bands through regular use.

Figure 1: The LDG RT-100 Remote Mount Tuner (left) and RC-100 Control Unit (right). The RT-100 is designed for outdoor installation, while the RC-100 provides power and control from the operating station.

2. Safety Information

Please read and understand all safety instructions before installing and operating the LDG RT-100 and RC-100. Failure to follow these instructions may result in injury, damage to equipment, or voiding of warranty.

• Electrical Safety: Always disconnect power to your radio equipment before making any connections to the tuner or antenna system. Ensure all coaxial cables are properly terminated and insulated.
• Outdoor Installation: When installing the RT-100 outdoors, ensure it is mounted securely to a stable structure, such as a mast or pipe, using the provided U-bolt. Avoid mounting near power lines or other electrical hazards.
• Lightning Protection: While the RT-100 is weatherproof, it does not provide lightning protection. Implement appropriate lightning arrestors and grounding techniques for your antenna system as per local electrical codes.
• Power Requirements: The RT-100 is powered via the coaxial cable from the RC-100. Ensure the RC-100 is connected to a stable DC power source within its specified voltage range.
• RF Exposure: Operate your radio equipment in accordance with all applicable RF exposure guidelines and regulations. Maintain a safe distance from the antenna during transmission.

3. Package Contents

Verify that all items are present in your package:

• LDG RT-100 Remote Mount Automatic Antenna Tuner
• LDG RC-100 Control Unit / Bias-T
• U-bolt for pipe mounting (for RT-100)
• Instruction Manual (this document)

4. Setup and Installation

Proper installation is key to the performance of your RT-100 tuner. Follow these steps carefully:

1. Mounting the RT-100 Tuner:

   Select a suitable outdoor location for the RT-100, ideally at or very close to the antenna feedpoint. Use the provided U-bolt to securely mount the RT-100 to a mast or pipe. Ensure the enclosure is oriented to allow water runoff and protect connectors.

2. Connecting the Antenna:

   Connect your antenna's coaxial cable to the "ANTENNA" connector on the RT-100. The RT-100 is designed for coax-fed antennas such as dipoles, verticals, V-beams, or any other coax-fed antenna. For random length, long wire, or ladder line fed antennas, an optional external Balun is required (not included).

3. Connecting the Coaxial Cable to the RC-100:

   Run a coaxial cable from your radio's antenna output to the "COAX TO TUNER" connector on the RC-100 control unit. This coaxial cable will carry both the RF signal and DC power to the RT-100 tuner.
4. Connecting the RC-100 to Power:

   Connect a suitable DC power supply (not included) to the power input on the RC-100. Ensure the power supply matches the voltage and current requirements specified by LDG Electronics for the RC-100. The RC-100 will then inject this DC power onto the coaxial cable to power the RT-100.

5. Connecting the RC-100 to the Radio:

   Connect a short coaxial jumper cable from the "COAX TO RADIO" connector on the RC-100 to your radio's antenna input.

6. Optional ATAS Mode Operation (for Yaesu FT-891, 991(A), 857(D), 897(D), 450(D), 100(D) radios):

   For specific Yaesu radios supporting ATAS mode, follow these steps:

   1. Place your radio into ATAS mode.
   2. Press the Push-To-Talk (PTT) button and then press the "Up" button on your microphone.
   3. The tuner will initiate a tuning cycle using approximately 10 watts of power.
   4. Once tuning is complete, you can operate normally.

5. Operation

The LDG RT-100 is designed for straightforward operation, offering both automatic and manual tuning capabilities.

5.1 Automatic Tuning

The RT-100 will automatically initiate a tuning cycle whenever the SWR on the transmission line exceeds a preset limit. This ensures optimal matching without manual intervention during frequency changes.

5.2 Manual Tuning

You can manually trigger a tuning cycle from the RC-100 control unit. This is useful for initial setup or when you wish to force a re-tune. Refer to the RC-100 manual for specific button functions.

5.3 Tuner Bypass

The RC-100 also provides an option to bypass the tuner, allowing the RF signal to pass directly to the antenna without impedance matching. This can be useful for testing or when using an antenna that is already perfectly matched.

5.4 Memory Tuning

The RT-100 features 2,000 memory locations. When you operate near a frequency that has been previously tuned, the tuner will recall the stored settings, resulting in a nearly instantaneous tune (approximately 0.1 seconds). The tuner learns and stores your favorite frequencies and bands as you use it, optimizing tuning speed over time.

5.5 Power Handling

The RT-100 is rated for 0.1 to 125 watts on SSB and CW modes. For digital modes, the maximum power handling is 30 watts.

5.6 Tuning Speed

A full tuning cycle typically takes between 0.1 to 6 seconds. When recalling settings from memory, tuning is significantly faster, completing in approximately 0.1 seconds.

6. Maintenance

The LDG RT-100 is designed for minimal maintenance due to its robust, weatherproof construction.

• Enclosure: The RT-100 features a weather-resistant ABS enclosure with gaskets, providing protection against environmental elements. Periodically inspect the enclosure for any signs of damage or degradation.
• Connectors: Ensure all coaxial connections are clean, tight, and free from corrosion. Apply a dielectric grease or weatherproofing compound to outdoor connections for added protection.
• Operating Temperature: The unit is designed to operate in temperatures ranging from -40°C to +70°C. Ensure it is not exposed to conditions outside this range.
• Cleaning: If necessary, clean the exterior of the RT-100 with a soft, damp cloth. Do not use harsh chemicals or abrasive cleaners.

7. Troubleshooting

If you encounter issues with your RT-100 tuner, refer to the following troubleshooting guide:

If these steps do not resolve your issue, please contact LDG Electronics customer support for further assistance.

8. Specifications

9. Warranty and Support

9.1 Warranty Information

All LDG tuners, including the RT-100, come with a two-year fully transferable warranty. This warranty covers defects in materials and workmanship under normal use. Please retain your proof of purchase for warranty claims.

9.2 Customer Support

For technical assistance, troubleshooting, or warranty service, please contact LDG Electronics customer support. You can typically find contact information on the official LDG Electronics website:

Visit LDG Electronics Support Page

When contacting support, please have your product model number (RT/RC-100) and a detailed description of the issue ready.