Astatic 636L

The Astatic 636L is a highly popular and durable dynamic noise-canceling microphone widely used for CB, amateur, and SSB radio communications, particularly in high-noise environments like commercial vehicles. It has been an industry standard for over 70 years.
Key Features and Specifications
The Astatic 636L is renowned for its ability to cut through background noise effectively.
Microphone Type: Dynamic noise-canceling element, designed for close-talking handheld applications.
Noise Cancellation: Provides 360-degree minimization of background noise, ensuring clear voice transmission.
Frequency Response: Tailored for voice communications, with a range of 100 to 5,000 Hz.
Impedance: Low impedance of approximately 200 ohms, compatible with most radios (matching 50 to 1000 ohms).
Connectivity: Equipped with a standard 4-pin connector, compatible with most 4-pin CB radios including Cobra, Uniden, and Galaxy models. Other pin configurations (e.g., 5-pin) may also be available.
Cord: Features a six-wire, five-conductor coiled cord with durable strain relief that extends to 7.5 feet. Some variations offer a stainless steel or armored cord.
Housing: Rugged construction using high-impact molded black ABS Cycolac with a polyurethane-coated steel grille screen for durability. It is also available in various finishes like chrome and carbon fiber.
Additional Features: Includes a soft vinyl lip guard to maintain proper close-talk spacing and a smooth-operating, long-life push-to-talk (PTT) switch.
User and Expert Opinions
Reviewers and users consistently praise the Astatic 636L for its performance in noisy settings.
Clarity: Praised for delivering clear, crisp audio that cuts through engine and wind noise effectively, making it a favorite among professional truckers and heavy equipment operators.
Durability: Users note its rugged construction stands up well to daily abuse and rough conditions in commercial vehicles.
Performance: According to some comparisons, it can out perform other popular microphones like the RK56 in noisy environments by focusing on voice frequencies and minimizing ambient sound.
Compatibility: Its standard 4-pin connection and broad impedance match make it a versatile upgrade for many stock CB radios.