The Collins R 390A URR is a legendary communications receiver that was widely used by the military and amateur radio operators in the mid-20th century. Known for its exceptional performance and durability, the R 390A URR quickly became a favorite among radio enthusiasts around the world.
Designed and manufactured by Collins Radio Company, the R 390A URR was first introduced in the late 1950s and remained in production until the early 1970s. It was primarily used for receiving AM, CW, and SSB signals in the frequency range of 0.5 to 32 MHz. The receiver’s impressive sensitivity and selectivity made it ideal for monitoring long-range communications, including military and diplomatic transmissions.
Despite being a vintage piece of equipment, the Collins R 390A URR continues to be highly sought after by radio collectors and enthusiasts. Its timeless design, exceptional performance, and historical significance make it a valuable addition to any radio collection. Whether you are a seasoned radio operator or a beginner in the world of radio communication, the R 390A URR is a must-have for anyone interested in experiencing the golden age of radio technology.
Overview of the Collins R 390A URR
The Collins R 390A URR is a high-performance communications receiver that was widely used by the military and amateur radio operators during the mid-20th century. It was manufactured by Collins Radio Company and is considered to be one of the most iconic and reliable receivers of its time.
The R 390A URR is a vacuum tube-based receiver that covers a frequency range of 0.5 to 32 MHz. It features a double-conversion superheterodyne architecture, which allows for excellent selectivity and sensitivity. The receiver is housed in a sturdy metal case and weighs approximately 85 pounds.
Features
The Collins R 390A URR offers a wide range of features that make it a versatile and powerful receiver. Some of its key features include:
- Variable bandwidth control: The receiver allows the user to adjust the bandwidth to optimize reception for different types of signals.
- Crystal filter: The R 390A URR is equipped with a crystal filter that provides additional selectivity and helps to reduce interference from adjacent signals.
- Automatic frequency control (AFC): The AFC feature helps to maintain accurate frequency tuning, even in the presence of drift or interference.
- Notch filter: The receiver includes a notch filter that can be used to suppress interference from a specific frequency or narrow band of frequencies.
- RF gain control: The RF gain control allows the user to adjust the sensitivity of the receiver to optimize reception in different conditions.
Specifications
| Frequency Range | |
|---|---|
| Number of Channels | 1 |
| Power Requirements | 115/230 VAC, 50/60 Hz |
| Dimensions | 19″ x 10.5″ x 17″ |
| Weight | Approximately 85 lbs |
Overall, the Collins R 390A URR is a highly capable and reliable communications receiver that offers excellent performance and a wide range of features. Whether used for military operations or amateur radio, this receiver continues to be highly regarded for its exceptional sensitivity and selectivity.
Features and Specifications of the Collins R 390A URR
The Collins R 390A URR is a high-performance communications receiver that was widely used by the military and amateur radio operators. It was first introduced in the 1950s and quickly gained popularity due to its exceptional sensitivity and selectivity.
Key Features
The Collins R 390A URR is packed with a range of features that make it a versatile and reliable receiver. Some of its key features include:
- Frequency Coverage: The receiver covers a wide frequency range from 0.5 kHz to 32 MHz, allowing users to tune into various bands and frequencies.
- Variable Bandwidth: It offers variable bandwidth options, allowing users to adjust the receiver’s selectivity to match the incoming signal.
- Crystal Filters: The R 390A URR is equipped with crystal filters that provide excellent adjacent channel rejection and help reduce interference.
- Automatic Frequency Control (AFC): The AFC feature ensures that the receiver stays locked onto the desired frequency, even in the presence of frequency drift.
- Notch Filter: It has a notch filter that helps eliminate unwanted signals or interference, allowing for clearer reception.
- Audio Output: The receiver provides a high-quality audio output, allowing users to listen to signals with clarity and fidelity.
Specifications
- Operating Modes: AM, CW, SSB
- Sensitivity: 0.5 µV for 10 dB Signal-to-Noise Ratio (SNR)
- Image Rejection: 80 dB
- Audio Output Power: 2 watts
- Power Requirements: 115/230 V AC, 50-60 Hz
The Collins R 390A URR is a robust and reliable receiver that offers exceptional performance and versatility. Whether used for military communications or amateur radio operations, it continues to be highly regarded for its outstanding features and specifications.
How to Use the Collins R 390A URR
Using the Collins R 390A URR is a straightforward process that requires some basic knowledge of its functions and controls. Here are the steps to effectively use this radio receiver:
1. Power On: Make sure the Collins R 390A URR is connected to a power source. Turn on the power switch located on the front panel of the receiver.
2. Frequency Selection: Use the tuning knob to select the desired frequency. The frequency can be displayed on the frequency dial located on the front panel.
3. Mode Selection: The Collins R 390A URR supports different modes of operation, such as AM, CW, and SSB. Use the mode selector switch to choose the appropriate mode for the desired signal.
4. Fine-tuning: Use the fine-tuning knob to adjust the signal reception. This allows for precise tuning and helps eliminate any unwanted noise or interference.
5. Volume Control: Adjust the volume control knob to set the desired audio level. This will determine the loudness of the received signal.
6. Antenna Selection: Connect the appropriate antenna to the antenna input of the Collins R 390A URR. Make sure the antenna is properly grounded for optimal performance.
7. Signal Reception: Once the receiver is properly set up, listen for the desired signals. Use the speaker or connect headphones to the headphone jack for private listening.
8. Fine-tuning and Filtering: Use the various tuning and filtering controls available on the Collins R 390A URR to enhance the received signal. These controls include bandwidth adjustment, notch filters, and IF gain control.
9. Recording: If desired, connect a recording device to the audio output of the Collins R 390A URR to capture and save the received signals for later analysis or playback.
10. Power Off: When finished using the Collins R 390A URR, turn off the power switch and disconnect it from the power source.
Troubleshooting and Maintenance of the Collins R 390A URR
Common Issues
Here are some common issues that users may encounter with the Collins R 390A URR:
| Issue | Possible Cause | Solution |
|---|---|---|
| No Power | Loose power cable connection | Check and secure power cable connection |
| Weak or No Signal | Antenna connection issue | Check antenna connection and ensure it is properly grounded |
| Interference | Proximity to other electronic devices | Move the Collins R 390A URR away from other electronic devices |
| Audio Distortion | Volume or tone control settings | Adjust volume and tone control settings |
Maintenance Tips
To keep your Collins R 390A URR in optimal condition, here are some maintenance tips:
- Regularly clean the exterior of the equipment using a soft cloth to remove dust and debris.
- Inspect the power cable and connectors for any signs of damage or wear. Replace if necessary.
- Check the antenna connections and ensure they are tight and secure.
- Periodically inspect the internal components for any signs of corrosion or loose connections.
- Keep the Collins R 390A URR in a clean and dry environment to prevent moisture damage.
- Follow the manufacturer’s recommended maintenance schedule for any required servicing or calibration.
By following these troubleshooting and maintenance tips, you can ensure that your Collins R 390A URR operates at its best and provides reliable performance for years to come.
Over the years, I have amassed a wealth of experience and knowledge, which I eagerly share with fellow radio aficionados. Through my writing and active participation in the amateur radio community, I strive to inspire others and provide valuable insights into this fascinating hobby. Engaging in various radio activities, I continue to learn and grow, constantly amazed by the endless possibilities that radio communication offers.