NATIONAL CNA-47160 Wwii Hro Plug Tuning Coil RAS-3 4.0-7.0

( Brand: National ), ( Manufacturer Part Number: CNA-47160 ), ( Model: 5 CNA-47160 ), ( Type: Coil ), ( Country Of Origin: United States )

Review NATIONAL Wwii Hro Us Navy Plug in Tuning Coil #5 4.0-7.0 Mc Type

The **National CN-A-47160 WWII-era HRO (High Range Oscillator) RAS-3 Plug-In Tuning Coil** is a meticulously crafted, vintage radio tuning coil designed for high-frequency applications, originally developed for military and high-end civilian radio receivers during World War II. This coil is part of the legendary **National CN-A series**, renowned for its precision engineering and reliability, and it specifically serves as a plug-in module for the **HRO (High Range Oscillator) tuning circuit**, a hallmark of early shortwave and military-grade radio technology. Built to operate within the **4.0 to 7.0 MHz range**, the RAS-3 coil is optimized for tuning high-frequency signals with exceptional selectivity and stability, making it ideal for both amateur radio enthusiasts and collectors seeking authentic, period-correct components for restoration projects.

The coil itself is constructed with **high-quality, finely wound copper wire** on a robust, insulated former, ensuring minimal energy loss and maximum efficiency in signal transmission. Its **plug-in design** allows for easy installation into compatible HRO-based receivers, such as the iconic **National HRO-5 or HRO-100**, where it enhances the receiver s ability to lock onto weak, high-frequency signals with precision. The RAS-3 coil s **adjustable tuning characteristics** are further refined by its integration with the HRO s variable inductance and capacitance circuits, enabling operators to fine-tune signals with remarkable clarity an essential feature for military communications, shortwave broadcasting, and early experimental radio work.

Beyond its technical prowess, the **CN-A-47160 RAS-3 coil** holds significant historical value as a relic of mid-20th-century radio innovation. Originally manufactured by **National Radio Company (later part of RCA)**, these coils were critical components in military and diplomatic communications, ensuring secure and reliable transmissions across vast distances. Today, they are highly sought-after by vintage radio restorers, ham radio operators, and collectors who appreciate the craftsmanship and engineering of an era when radio technology was at the forefront of global connectivity. Whether used in a fully restored HRO receiver or as a standalone tuning element in a modern build, this coil embodies the durability and performance that defined early radio engineering a true piece of technological history.

**Pros and Cons of buying a National CNA-47160 WWII HRO RAS-3 Plug-In Tuning Coil (4.0-7.0 MHz)**

### **Pros**

1. **Historical Significance and Authenticity**

The National CNA-47160 is a reproduction of a tuning coil used in vintage WWII-era radio receivers, particularly the Hallicrafters S-38 and similar models. For collectors and enthusiasts of classic radio technology, this coil offers a tangible connection to mid-20th-century radio engineering. The attention to detail in its construction including the RAS-3 plug-in design makes it a desirable piece for those who appreciate period-correct hardware.

2. **Compatibility with Vintage Receivers**

The coil is designed to fit into receivers that originally used the RAS-3 plug-in tuning coil system, such as the Hallicrafters S-38, SX-110, and other WWII-era radios. This makes it a practical upgrade or replacement for collectors who want to restore or enhance the performance of their vintage setups. The 4.0-7.0 MHz range is particularly useful for shortwave listening, which was common in military and civilian communications during WWII.

3. **Improved Performance for Shortwave Listening**

The coil is optimized for the shortwave bands, which were critical for long-distance communication during WWII. While the original coils may have had limitations in selectivity or coverage, a well-made reproduction like this can offer improved tuning stability and signal clarity. This can be beneficial for modern shortwave listeners who want to experiment with vintage gear while enjoying better performance than some original units might provide.

4. **Craftsmanship and Quality**

Reputable manufacturers of vintage radio parts often use high-quality materials and construction techniques to replicate original components. This coil is likely built to last, with proper insulation, winding precision, and durable connectors. For those who value durability and reliability in their radio equipment, this can be a significant advantage over cheaper or poorly made aftermarket parts.

5. **Educational Value**

Owning and using this coil can be an educational experience, allowing enthusiasts to learn about the inner workings of vintage radio technology. Understanding how tuning coils function in older receivers can deepen appreciation for radio history and the principles of radio frequency engineering.

6. **Aesthetic Appeal**

The coil s vintage design, with its brass or metal casing and plug-in connectors, adds a classic look to any radio setup. For collectors who enjoy the visual and tactile aspects of vintage electronics, this coil can be a pleasing addition to a display or functional radio.

---

### **Cons**

1. **Limited Frequency Range**

The coil is specifically designed for the 4.0-7.0 MHz range, which is narrow compared to modern multi-band coils. If you plan to use it in a receiver that requires broader coverage (e.g., 1.5-30 MHz), you may need additional coils or a more versatile tuning unit. This limitation can be frustrating for listeners who want to cover a wider range of frequencies without switching coils manually.

2. **Compatibility Issues with Modern Receivers**

While the coil fits into WWII-era receivers, it may not be compatible with modern or non-RAS-3 plug-in systems. If you re using a contemporary receiver that doesn t support plug-in coils, this purchase may be irrelevant or require additional modifications to the radio. Always verify compatibility before buying.

3. **Potential for Inconsistent Quality**

Reproductions, even from reputable manufacturers, can vary in quality. Some coils may have loose windings, poor insulation, or connectors that don t fit perfectly. If the coil is not well-made, it could lead to tuning instability, arcing, or even damage to the receiver over time. Buying from a trusted seller with good reviews can mitigate this risk, but it s still a consideration.

4. **Cost Relative to Modern Alternatives**

Vintage radio parts, especially high-quality reproductions, can be expensive. For a coil that covers a limited frequency range, the cost may not justify the purchase if you re primarily interested in modern shortwave listening. Modern multi-band coils or even digital receivers may offer better value for general use.

5. **Maintenance and Longevity Concerns**

Like all vintage components, this coil may require occasional maintenance to ensure optimal performance. Dust, oxidation, or wear on the connectors could affect functionality over time. While well-made reproductions are durable, they may not last as long as modern components, especially if exposed to harsh conditions (e.g., humidity, temperature fluctuations).

6. **Learning Curve for Vintage Operation**

Using a WWII-era receiver with a plug-in coil may require familiarity with older tuning techniques, such as manual coil switching, variable capacitors, and possibly even vacuum tube operation. If you re not already experienced with vintage radios, the learning curve could be steep, and the process of setting up and troubleshooting may be more time-consuming than with modern gear.

7. **Availability of Spares and Support**

If something goes wrong with the coil or the receiver it s used in, finding replacement parts or technical support can be challenging. Vintage radio communities and forums exist, but they may not offer the same level of immediate assistance as modern manufacturers. This could be a drawback if you encounter issues that require expert intervention.

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### **Conclusion**

The National CNA-47160 WWII HRO RAS-3 plug-in tuning coil is a fascinating and functional piece for enthusiasts of vintage radio technology. It excels in historical authenticity, compatibility with classic receivers, and the unique experience of using WWII-era components. For collectors, restorers, or shortwave listeners who appreciate the charm and challenge of vintage gear, this coil offers a rewarding addition to their setup.

However, its narrow frequency range, potential compatibility issues with non-vintage receivers, and higher cost relative to modern alternatives may not make it practical for everyone. If your primary goal is broad-band shortwave listening or modern convenience, a contemporary coil or receiver might be a better investment. On the other hand, if you re drawn to the nostalgia, craftsmanship, and educational value of vintage radio parts, this coil is a worthwhile purchase for the right enthusiast.

### **Recommendation**

- You own or plan to restore a WWII-era receiver that uses the RAS-3 plug-in system (e.g., Hallicrafters S-38, SX-110).

- You re interested in shortwave listening within the 4.0-7.0 MHz range and enjoy the experience of using authentic vintage components.

- You value historical radio technology and are willing to invest in a high-quality reproduction for educational or collector purposes.

- You re prepared to troubleshoot or seek out vintage radio communities for support if issues arise.

- You need a coil with a broader frequency range or modern compatibility.

- You re primarily looking for cost-effective, easy-to-use shortwave listening solutions.

- You lack experience with vintage radios and are unwilling to invest time in learning or maintaining older equipment.

- You cannot verify the coil s quality or compatibility with your specific receiver before purchasing.

For most enthusiasts, this coil is best suited as a specialized addition to a vintage radio collection rather than a general-purpose upgrade. Pair it with other coils or receivers if you need broader coverage, and always source it from a reputable seller to ensure authenticity and quality.

Details:

Four ship options provided. Untested, 4.0-7.0 Mc range. If you notice an error in my listing please let me know so I can correct it.

Offered up here is this tuning coil set for the US Navy HRO model RAS-3 receiver. Sometimes I get in just too much of a hurry don't pay close enough attention. Offered as-is as described and pictured.

part #: cna47160 price

• $17.50

specifications hamamateuradio:

• brand: National
• mpn: Cna-47160
• model: 5 Cna-47160
• type: Coil
• country of origin: United States

seller hamamateuradio:

• # reviews: 5434
• rating: 100.0%
• city: Crete, Illinois

offer hamamateuradio:

• availability: In Stock
• quantity: 1
• best offers: True
• sold: 0
• started: March 6, 2026
• options: Ship-to-home

general hamamateuradio:

• condition: For parts or not working
• Radio Communication > Ham, Amateur Radio > Ham Radio Receivers

shipping hamamateuradio:

• class: Standard, Expedited, Economy
• transit: 4-8 Days
• service: USPS Ground Advantage, USPS Priority Mail, FedEx Ground / FedEx Home Delivery, FedEx Ground Economy
• carrier: USPS, FedEx
• cost: $9.84
• type: Calculated

payments hamamateuradio:

• cash
• wallet: Google-pay
• credit card: Diners-club
• other

returns hamamateuradio:

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

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