OREN ELLIOTT 73-1-30-55A Air Capacitor

( Brand: Oren Elliott ), ( Manufacturer Part Number: 73-1-30-55A ), ( Compatible Brand: Universal ), ( Type: Capacitor )

Review OREN ELLIOTT Air Variable Capacitor

The **Oren Elliott 73-1-30-55A Air Capacitor** is a precision-engineered, high-performance variable air capacitor designed for demanding RF (radio frequency) and electronic applications where reliability, stability, and fine-tuning capability are paramount. This capacitor belongs to the **73 series**, a line renowned for its exceptional construction and performance in critical circuit applications, including amateur radio transmitters, VHF/UHF antennas, and experimental RF setups. Crafted with meticulous attention to detail, the 73-1-30-55A features a **rotary tuning mechanism** with a **30-pF minimum capacitance** and a **55-pF maximum capacitance**, allowing operators to achieve precise adjustments across a broad range of frequencies. The capacitor s **air-dielectric design** ensures minimal loss and high Q-factor, making it ideal for applications where signal integrity and efficiency are non-negotiable.

The physical construction of the 73-1-30-55A is robust yet elegant, with a **durable metal housing** that provides both mechanical stability and electromagnetic shielding, reducing stray capacitance and interference. The **rotary shaft** is sealed with precision bearings to ensure smooth, backlash-free operation, while the **adjustment knob** is ergonomically designed for easy manual tuning without slippage. The capacitor s **terminals** are solder lugs, offering secure and flexible connection options, whether for direct wiring or breadboarding. This model is particularly well-suited for **amateur radio enthusiasts** working with **HF (High Frequency) or VHF (Very High Frequency) bands**, as well as **experimentalists** building custom RF filters, oscillators, or antenna tuners.

Beyond its technical specifications, the 73-1-30-55A embodies the legacy of Oren Elliott s commitment to **handcrafted quality and performance**. Each unit is built to exacting standards, ensuring consistent performance over extended use. The air-dielectric material not only eliminates the risk of dielectric absorption or aging, which can plague solid-dielectric capacitors, but also maintains a **flat frequency response** across its operating range. This makes the 73-1-30-55A an excellent choice for **critical tuning applications**, such as in **QRP (low-power) transmitters**, **antenna matching networks**, or **resonant circuits** where even minor deviations in capacitance could degrade performance. Whether integrated into a **custom-built rig** or used as a replacement in vintage or modern equipment, this capacitor delivers the **precision, durability, and reliability** expected from a premium RF component.

**Pros and Cons of buying a Oren Elliott 73-1-30-55A Air Capacitor**

The Oren Elliott 73-1-30-55A is a high-quality air capacitor commonly used in vintage and modern radio restoration, amateur radio projects, and audio applications. Below is a detailed breakdown of its advantages and disadvantages.

### **Pros**

1. **High Reliability and Durability**

The Oren Elliott brand is well-regarded for producing capacitors that are built to last. Air capacitors, in particular, are known for their long lifespan, as they lack dielectric materials that degrade over time. This makes them ideal for critical applications where reliability is essential.

2. **Precision and Stability**

Air capacitors offer extremely stable capacitance values with minimal drift over time or temperature changes. This makes them suitable for frequency-sensitive applications, such as radio tuning circuits, where accuracy is crucial.

3. **Low Loss and High Q Factor**

Unlike electrolytic or film capacitors, air capacitors exhibit very low dielectric loss, resulting in a high Q factor (quality factor). This is beneficial in RF (radio frequency) circuits, where efficiency and signal purity are important.

4. **Wide Frequency Range**

The 73-1-30-55A is designed for high-frequency applications, making it suitable for use in transmitters, receivers, and other RF circuits where standard capacitors might not perform as well.

5. **Adjustability (If Applicable)**

Some air capacitors, including certain models in this series, are variable or trimmer types. While the 73-1-30-55A appears to be a fixed-value capacitor, similar Oren Elliott air capacitors are often used in tuning circuits where fine adjustments are necessary.

6. **Compatibility with Vintage Equipment**

Many classic radios, particularly those from the mid-20th century, were designed with air capacitors. Replacing original components with modern but high-quality air capacitors ensures compatibility and restores performance without introducing modern dielectric issues.

7. **No Aging or Leakage Concerns**

Unlike electrolytic capacitors, air capacitors do not suffer from aging, leakage, or polarization effects. This eliminates common failure modes associated with other capacitor types.

8. **High Voltage Ratings**

Air capacitors can often handle higher voltage ratings than their solid-state counterparts, making them suitable for applications where voltage stability is required.

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### **Cons**

1. **Higher Cost**

Air capacitors are significantly more expensive than standard electrolytic or ceramic capacitors. This makes them a less economical choice for non-critical applications where cheaper alternatives would suffice.

2. **Bulkiness and Physical Size**

Air capacitors tend to be larger and heavier than solid-state capacitors. This can be a drawback in space-constrained projects or when replacing components in compact equipment.

3. **Limited Availability**

While Oren Elliott is a reputable brand, air capacitors are not as widely stocked as common capacitor types. Sourcing them may require special orders or purchases from specialized suppliers, which can add to the cost and delay.

4. **Sensitivity to Mechanical Stress**

Air capacitors, particularly variable or trimmer types, can be sensitive to mechanical stress or misalignment. Improper handling or installation may lead to performance degradation or failure.

5. **Not Ideal for Low-Frequency Applications**

While air capacitors excel in RF and high-frequency applications, they are less efficient at low frequencies. For applications requiring large capacitance at low frequencies, other capacitor types (e.g., electrolytics or film) may be more practical.

6. **Potential for Misalignment in Variable Types**

If the 73-1-30-55A or similar models are variable, improper adjustment can lead to inconsistent performance or even damage. This requires careful handling and expertise.

7. **Limited Current Handling**

Air capacitors generally have lower current-handling capabilities compared to some solid-state capacitors. In high-power applications, this may necessitate additional components or design considerations.

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### **Conclusion**

The Oren Elliott 73-1-30-55A air capacitor is an excellent choice for applications requiring precision, stability, and reliability particularly in RF circuits, vintage radio restoration, and high-frequency tuning applications. Its lack of aging, low loss, and high Q factor make it a superior option in these contexts. However, its high cost, bulkiness, and limited availability may make it impractical for budget-conscious or low-frequency projects.

For most **RF and high-frequency applications**, the benefits of using an air capacitor far outweigh its drawbacks. If you are working on a project where accuracy, longevity, and minimal signal loss are critical such as a restored vintage radio, a high-performance transmitter, or a sensitive receiver the Oren Elliott 73-1-30-55A is a strong recommendation.

For **low-frequency or general-purpose applications**, where cost and space are concerns, standard electrolytic or film capacitors may be more appropriate. Always ensure that the capacitor s specifications (voltage, capacitance range, and frequency response) align with your project s requirements before purchasing.

If you are restoring a classic radio, building a high-frequency circuit, or working on an application where signal integrity is paramount, **purchasing the Oren Elliott 73-1-30-55A is highly recommended**. Its superior performance and longevity justify the higher cost. However, if your project does not require air capacitor benefits, consider more cost-effective alternatives. Always verify compatibility and consult technical specifications before finalizing your purchase.

Details:

If you notice these do not have feet to bolt down. These were used in RF matching circuits and isolated from ground. Sale is for Notice one has marker on plate.

Capacitors in good shape. If you include a note at time of purchase I will 2 the mounting tabs that make these easily mountable.

part #: 7313055a price

• $75.00

specifications hamamateuradio:

• brand: Oren Elliott
• mpn: 73-1-30-55a
• compatible brand: Universal
• type: Capacitor

shipping hamamateuradio:

• service: USPS Ground Advantage
• transit: 4-9 Days
• type: Calculated
• cost: $14.00
• class: Standard
• carrier: USPS

offer hamamateuradio:

• availability: In Stock
• sold: 0
• started: January 31, 2026
• quantity: 2
• options: Ship-to-home

general hamamateuradio:

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

seller hamamateuradio:

• rating: 100.0%
• city: Louisville, Kentucky
• # reviews: 4648

returns hamamateuradio:

• policy: No Returns

payments hamamateuradio:

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

Oren Elliott 73-1-30-55A Is Similar To:

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