📡 RVR TEX‑502 LCD Transmitter – Repair & Maintenance Guide

✍️ Written by: TB7AEK Ayberk Efe Korkmaz

AYBERK BLOG

Ayberk Efe Korkmaz

7/31/20251 min read

📡 RVR TEX‑502 LCD Transmitter – Repair & Maintenance Guide

✍️ Written by: TB7AEK Ayberk Efe Korkmaz

🔍 Overview

The TEX‑502 LCD is a professional-grade 500 W FM transmitter built by 🇮🇹 R.V.R. Elettronica. Known for its compact 2U rack design, high efficiency (>70%), and crystal-clear audio quality, it is widely used in radio broadcast stations across the globe 🌍.

⚙️ Key Features

  • 🎛️ Frequency Range: 87.5 – 108 MHz

  • ⚡ Adjustable Output Power: 10%–100% (up to 500 W)

  • 🎶 Modulation Types: Mono / Stereo / MPX

  • 📦 Design: Sturdy steel case, weighs ~9.5 kg

  • 🔌 Inputs/Outputs:

    • XLR (L/R Audio)

    • BNC (MPX / SCA / RDS)

    • Optional: AES/EBU Digital Input

  • 🛡️ Built-in Protections:

    • APC (Automatic Power Control)

    • Overheat/Foldback

    • PFC (Power Factor Correction)

🚨 Common Failures & Symptoms

  1. 🖥️ Frozen LCD Screen
    → Could be power supply or firmware-related

  2. 📉 Low RF Output / Dropouts
    → RF module damage, fan failure, or PSU issues

  3. 📡 RDS / SCA Data Malfunction
    → Encoder fault or connector issues

  4. 🔥 Overheating / Fan Stoppage
    → Dust buildup or motor failure

  5. 🌐 Remote Monitoring Not Working (Web/GSM/SNMP)
    → Communication board or software fault

🛠️ Step-by-Step Repair Guide

1️⃣ Initial Diagnostics

  • 🔍 Check Voltages (AC input, 5V/12V rails, fan power)

  • 💡 Verify LCD Backlight Power (typically 5V supply)

  • 📶 Test RF Output using a spectrum analyzer or wattmeter

  • 🧠 Analyze Logs for GSM/RDS/Telemetry faults

2️⃣ Hardware Troubleshooting

  • 🧰 Replace faulty modules (e.g., LCD panel, fan)

  • 🧽 Clean internals, reapply thermal paste

  • 🔧 Reseat connectors and check solder joints

3️⃣ Software & Calibration

  • 🔁 Reset to Factory Defaults if needed

  • 📏 Recalibrate Power Output & Frequency

  • 🌐 Reconfigure Web/GSM/SNMP Settings

4️⃣ Final Testing

  • 📡 Power up gradually (start from 20%, increase step-by-step)

  • ✅ Check output stability, audio clarity, and RDS data

  • 📑 Log test results and certify for use

🧼 Preventive Maintenance Tips

  • 🔄 Every 3 months:

    • Clean fans & filters 🧹

  • 💽 Every 6 months:

    • Check for firmware updates

  • 📐 Annually:

    • Recalibrate APC & frequency

  • 📦 Always:

    • Keep spare parts (LCD, fan, PSU) on hand

⚠️ Safety Notes

  • ⚡ Disconnect AC power before service

  • 🧲 Use ESD-safe tools when working on boards

  • 📏 Always follow RF safety standards and local regulations

🧾 Final Thoughts

The TEX‑502 LCD is a reliable and flexible FM transmitter designed for both professionals and hobbyists 🎙️. With proper diagnostics, careful repair, and regular maintenance, it can provide years of uninterrupted broadcasting 📻.

✉️ Authored by:

TB7AEK Ayberk Efe Korkmaz
🔧 Licensed Amateur Radio Operator | RF Enthusiast | Repair Specialist