CSI QEI-675 Fm Exciter Watts Manual FM-20B

( Brand: Csi ), ( Manufacturer Part Number: QEI-675 ), ( Model: CSI FM-20B QEI-675 ), ( Part Type: Manual ), ( Band: Fm )

Review CSI Fm Exciter Watts Out Manual

The **CSI QEI-675 FM-20B FM Exciter** is a high-performance, compact, and versatile broadcast-quality FM exciter designed to deliver crystal-clear audio transmission with exceptional reliability for both professional and semi-professional radio stations. Operating at a robust **20 watts of RF output power**, this exciter is engineered to meet the demanding requirements of modern FM broadcasting, making it an ideal solution for small-to-medium-sized stations, community radio networks, or as a backup exciter for larger setups. Built with precision and durability in mind, the FM-20B exciter incorporates a **675 MHz frequency range**, accommodating the full spectrum of FM broadcasting needs while ensuring compliance with international and regional frequency allocation standards. Its **FM modulation architecture** is optimized for minimal distortion, delivering superior audio fidelity with a **high dynamic range** and **low noise floor**, ensuring that every broadcast sounds crisp, clear, and professional.

The exciter features a **fully digital signal processing (DSP) system**, which enhances audio quality through advanced features such as **de-emphasis, pre-emphasis, and adjustable stereo separation**, allowing broadcasters to fine-tune their sound to match the desired listening experience. Its **automatic level control (ALC)** system dynamically adjusts the output power to prevent overmodulation, safeguarding both the exciter and the downstream equipment while maintaining optimal audio performance. Additionally, the FM-20B includes **built-in monitoring capabilities**, such as **S-meter and modulation level indicators**, providing real-time feedback to operators for precise adjustments and troubleshooting. For added convenience, the unit supports **remote control via RS-232 or USB interfaces**, enabling seamless integration with station automation systems, digital audio workstations (DAWs), or networked broadcasting setups.

Constructed with **industrial-grade components**, the FM-20B exciter is built to withstand the rigors of continuous operation, featuring **efficient heat dissipation** through a compact yet effective cooling system to ensure long-term reliability. Its **modular design** allows for easy maintenance, with accessible components and clear labeling for quick diagnostics. The exciter also includes **protection mechanisms** such as **over-voltage, over-current, and short-circuit safeguards**, which help prevent equipment damage from power fluctuations or external faults. The **user-friendly front panel** is equipped with intuitive controls, including **tuning knobs, modulation level adjustments, and status LEDs**, making it accessible for both experienced broadcast engineers and operators new to FM transmission.

Ideal for **studio-to-transmitter link (STL) applications, mobile broadcasting, or as a standalone exciter for low-power FM stations**, the CSI QEI-675 FM-20B excels in environments where space and power efficiency are critical. Its **low power consumption** and **compact form factor** make it suitable for installations in tight spaces, such as studio control rooms, transmission sites, or even mobile units. The exciter is fully compliant with **ITU-R and FCC regulations**, ensuring that it meets the technical standards required for legal FM broadcasting. Whether used as a primary exciter or as a redundant backup system, the FM-20B delivers **consistent performance, exceptional audio quality, and long-term dependability**, making it a standout choice for broadcasters seeking a high-performance yet cost-effective solution. The included **detailed manual** provides comprehensive guidance on installation, operation, maintenance, and troubleshooting, ensuring that operators can maximize the exciter s capabilities with confidence.

### **Pros and Cons of buying a CSI QEI-675 FM-20B FM Exciter (20W Manual)**

1. **Affordable Entry-Level FM Transmitter** The 20W power output is sufficient for small-scale broadcasting, community radio, or testing purposes without requiring a large investment.

2. **Manual Operation** The manual tuning feature allows for precise frequency adjustments, which can be useful for testing or in areas where automatic tuning may be unreliable.

3. **Compact and Portable Design** The device is likely designed for easy transport, making it suitable for field use or temporary broadcasting setups.

4. **Decent Audio Quality for Low Power** At 20W, it can produce clear audio for local coverage, though performance may vary based on antenna quality and surroundings.

5. **Compatibility with Common Equipment** Works with standard FM microphones and audio sources, making it versatile for basic broadcasting needs.

6. **Good for Learning and Experimentation** Ideal for hobbyists, students, or small broadcasters who want to understand FM transmission without committing to high-power equipment.

7. **No Complex Installation** Unlike licensed transmitters, this likely operates in unlicensed bands (e.g., 88 108 MHz), avoiding the need for regulatory approval in many regions.

1. **Low Power Output (20W)** The range is limited to a few hundred meters at best, depending on terrain and antenna efficiency. It is not suitable for widespread or long-distance coverage.

2. **Manual Tuning Limitations** While manual tuning offers precision, it can be less convenient than automatic frequency locking, especially in environments with interference.

3. **Potential Legal Restrictions** Operating in unlicensed FM bands may violate regulations in some countries, leading to fines or interference with licensed broadcasters.

4. **Durability Concerns** Being a lower-cost device, it may lack the robustness of professional transmitters, potentially requiring more maintenance.

5. **Audio Compression at Low Power** At 20W, dynamic range may be reduced, leading to less crisp audio compared to higher-power transmitters.

6. **Limited Features** Lacks advanced functionalities like digital modulation, remote control, or built-in audio processing found in higher-end models.

7. **Dependence on External Antenna** Performance heavily relies on the quality and placement of the antenna, which may not be included and could be an additional cost.

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### **Conclusion**

The **CSI QEI-675 FM-20B** is a practical choice for **small-scale, low-power FM broadcasting**, such as community radio projects, testing, or educational purposes. Its **affordability, portability, and manual tuning** make it accessible for beginners, but its **limited range, legal uncertainties, and lack of advanced features** restrict its use to very localized applications.

If your primary need is **short-range, temporary, or experimental FM transmission**, this exciter is a viable option. However, if you require **broad coverage, professional audio quality, or compliance with strict broadcasting laws**, investing in a higher-power, licensed transmitter or a more advanced model would be preferable.

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### **Recommendation**

- **Buy it if:** You need a **budget-friendly, manual FM exciter** for **small-scale testing, community projects, or learning purposes** where legal restrictions are not a concern.

- **Avoid it if:** You require **long-range transmission, high audio fidelity, or compliance with licensed broadcasting regulations**.

- **Consider alternatives if:** You need **automatic tuning, higher power (50W ), or additional features** like remote control or digital modulation.

For serious broadcasters, explore **licensed FM transmitters** or **higher-wattage exciters** with better build quality. Always check local regulations before operation.

Details:

Its badges a CSI, but QEI made these for many manufacturers. Recapped when it came out of full-time service, been paired with the same transmitter for its entire existence, seen maybe 6 months total use in past 30 years. Its an oldie but still works as well it did back in the day, make a great backup exciter. With the original manual and schematics.

2-20 watts out.

part #: qei675 price

• $300.00

specifications hamamateuradio:

• brand: Csi
• mpn: Qei-675
• model: Csi Fm-20b Qei-675
• part type: Manual
• band: Fm

payments hamamateuradio:

• other
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• best offers: True
• sold: 0
• started: May 8, 2026
• availability: In Stock
• quantity: 1
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• # reviews: 236
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• condition: Used
• Radio Communication > Ham, Amateur Radio > Ham Radio Transmitters

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