TX RX SYSTEMS 28-70-02-A Vari Notch Duplexer Watts Tuning 450-470 350

( Brand: Tx Rx Systems ), ( Manufacturer Part Number: 28-70-02-A ), ( Compatible Brand: Universal ), ( Type: Duplexer ), ( Mount Type: 19 Rack Mount ), ( Band: Uhf 450-470 Mhz ), ( Features: 350 Watts Capable )

Review TX RX SYSTEMS Vari notch Duplexer Model 450-470 Mhz 350 Watts Free Tuning

The **RX-28-70-02-A Vari-Notch Duplexer (450 470 MHz, 350W Tuning)** is a high-performance, dual-band radio frequency (RF) filtering solution engineered for demanding applications in amateur radio, emergency communications, and professional mobile radio (PMR) systems. Designed with precision and versatility in mind, this duplexer excels in isolating transmit and receive signals across the 450 470 MHz frequency range while maintaining exceptional efficiency and minimal insertion loss. Its **Vari-Notch** technology enables dynamic notch filtering, allowing operators to suppress unwanted interference or block specific frequencies without compromising signal integrity. Built to handle **350 watts of continuous RF power**, the RX-28-70-02-A ensures robust performance in high-power applications, making it ideal for repeaters, base stations, and mobile setups where signal purity and reliability are critical. The duplexer s compact yet rugged construction incorporates high-quality materials, including low-loss dielectric substrates and precision-machined waveguides, to deliver consistent performance across a wide temperature range. Whether deployed in a fixed installation or integrated into a mobile rig, this duplexer provides seamless frequency separation, reducing the risk of desensitization and cross-modulation while enhancing overall system clarity. Its **duplexer configuration** comprising a transmit/receive filter pair ensures that transmit signals are effectively isolated from the receiver path, preventing damage to sensitive front-end components and maximizing dynamic range. With its **broadband tuning capability**, the RX-28-70-02-A adapts effortlessly to varying signal conditions, making it a dependable choice for operators requiring flexibility in frequency management. Suitable for both new installations and retrofitting existing systems, this duplexer represents a blend of advanced RF engineering and practical performance, ensuring reliable operation in even the most challenging communication environments.

**Pros and Cons of buying a RX 28-70-02-A Vari-Notch Duplexer (450-470 MHz, 350 Watts)**

### **Pros**

1. **Frequency Coverage and Flexibility**

The duplexer is designed for the 450-470 MHz band, which is widely used for public safety, land mobile, and some private radio applications. This makes it suitable for a broad range of communication needs, including two-way radio systems, emergency services, and commercial operations. The ability to handle both transmit and receive signals in this range without interference is a significant advantage.

2. **High Power Handling (350 Watts)**

With a power rating of 350 watts, this duplexer is capable of handling high-power transmissions, which is essential for long-range communication or applications requiring robust signal strength. This makes it suitable for professional or industrial use where signal integrity and reliability are critical.

3. **Vari-Notch Design**

The vari-notch feature allows for dynamic filtering of specific frequencies, which can be useful in environments with potential interference or when tuning out unwanted signals. This adaptability can improve overall system performance by reducing noise and crosstalk.

4. **Duplexer Functionality**

A duplexer enables simultaneous transmission and reception on the same antenna, which is a space-saving and cost-effective solution compared to separate transmit and receive antennas. This is particularly beneficial in applications where antenna space is limited or where a single antenna must serve multiple functions.

5. **Durability and Reliability**

High-quality duplexers like this one are typically built to withstand harsh environmental conditions, including temperature fluctuations, humidity, and mechanical stress. This ensures long-term reliability, which is crucial for mission-critical communication systems.

6. **Compatibility with Existing Systems**

If you already have equipment operating in the 450-470 MHz range, this duplexer can integrate seamlessly into your setup, reducing the need for additional hardware or modifications. It is likely designed to work with standard connectors (e.g., N-type or UHF connectors), which are common in professional radio systems.

7. **Reduced Signal Loss**

A well-designed duplexer minimizes signal loss during transmission and reception, ensuring that your communication system operates efficiently. This is particularly important in applications where signal strength and clarity are paramount.

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### **Cons**

1. **Cost**

High-quality duplexers, especially those with advanced features like vari-notch functionality and high power handling, can be expensive. The initial investment may be a significant factor, particularly for smaller organizations or individual users. Additionally, there may be ongoing costs for maintenance or replacement if the duplexer fails prematurely.

2. **Complexity in Setup and Tuning**

Duplexers require careful installation and tuning to ensure optimal performance. Improper setup can lead to signal interference, reduced efficiency, or even damage to the equipment. Users may need technical expertise or professional assistance to install and configure the duplexer correctly, which can add to the overall cost and complexity.

3. **Limited Frequency Range**

While the 450-470 MHz range is useful, it is not universal. If your application requires operation outside this range, this duplexer will not be compatible, and you would need additional equipment. This limitation may restrict its use in certain industries or regions where different frequency bands are standard.

4. **Potential for Signal Degradation**

Even with high-quality components, duplexers can introduce some level of signal loss or distortion, particularly if they are not properly matched to the system s impedance or if there are issues with the connectors or cables. This could affect the clarity and range of your communication.

5. **Maintenance Requirements**

Like any electronic component, a duplexer may require periodic maintenance to ensure continued performance. This could include cleaning connectors, checking for corrosion, or recalibrating the vari-notch settings. Neglecting maintenance could lead to reduced lifespan or failure during critical operations.

6. **Compatibility Issues with Older Equipment**

If you are integrating this duplexer with older or non-standard equipment, there may be compatibility issues. For example, connector types, power requirements, or signal processing standards might not align, requiring additional adapters or modifications.

7. **Risk of Overloading**

While the duplexer is rated for 350 watts, exceeding this power limit even temporarily could damage the internal components. Users must ensure that their transmitters are properly rated and that the duplexer is not subjected to power spikes or overload conditions.

---

### **Conclusion**

The **RX 28-70-02-A Vari-Notch Duplexer (450-470 MHz, 350 Watts)** is a robust and versatile piece of equipment well-suited for professional or industrial applications requiring high-power, dual-band communication. Its vari-notch functionality, wide frequency coverage, and ability to handle significant power make it a strong choice for systems where reliability and performance are critical. However, the high cost, complexity of installation, and potential maintenance requirements should be carefully considered before purchase.

- Public safety agencies (police, fire, EMS) operating in the 450-470 MHz range.

- Commercial or industrial two-way radio systems where a single antenna must serve both transmit and receive functions.

- Applications requiring dynamic interference suppression (e.g., environments with frequent signal conflicts).

For users with limited technical expertise or those operating in environments outside the 450-470 MHz range, the duplexer may not be the best fit. Additionally, organizations with tight budgets should weigh the long-term benefits against the upfront cost and potential maintenance expenses.

---

### **Recommendation**

If your communication system operates within the **450-470 MHz band** and requires **high-power, dual-band functionality with dynamic interference suppression**, the **RX 28-70-02-A Vari-Notch Duplexer** is a strong and reliable investment. Ensure that:

1. Your existing equipment is compatible with the duplexer s connectors and power requirements.

2. You have the technical knowledge or resources to install and maintain it properly.

3. The duplexer s specifications align with your maximum power and frequency needs.

For users with simpler needs or those operating in different frequency ranges, a standard duplexer or a simpler filtering solution might be more cost-effective. Always consult with a radio frequency (RF) specialist or manufacturer recommendations to confirm compatibility and optimal performance.

Details:

TX RX Vari-Notch Duplexer. Let me know if you would like to tune the Duplexer for your Frequency Free. Good Condition. Model # 28-70-02-A.

Capable of Handling 350 watts Power. 5 Mhz of TX RX Separation. 450-470 MHz Band.

part #: 287002 price

• $575.00

specifications hamamateuradio:

• brand: Tx Rx Systems
• mpn: 28-70-02-a
• compatible brand: Universal
• type: Duplexer
• mount type: 19 Rack Mount
• band: Uhf 450-470 Mhz
• features: 350 Watts Capable

shipping hamamateuradio:

• transit: 5-11 Days
• type: Calculated
• carrier: USPS
• service: USPS Ground Advantage
• class: Standard
• cost: $25.74

returns hamamateuradio:

• paid by: Buyer
• method: Money back
• policy: Returns Accepted
• time: 14 Days

payments hamamateuradio:

• credit card: Visa
• other
• wallet: Google-pay

offer hamamateuradio:

• options: Ship-to-home
• quantity: 1
• started: May 26, 2026
• availability: In Stock
• sold: 0

seller hamamateuradio:

• city: Venice, Florida
• rating: 100.0%
• # reviews: 770

general hamamateuradio:

• Radio Communication > Ham, Amateur Radio > Other Ham Radio Equipment
• condition: Used

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