Best Metal Detectors for Coin Hunting: Tested and Reviewed The Detector Lab, November 10, 2024November 30, 2024 Whether you’re a seasoned treasure hunter or just starting out, finding coins can be both thrilling and rewarding. With countless metal detectors on the market, choosing the right one can seem overwhelming. In this guide, we’ll explore some of the best metal detectors specifically designed to help you unearth those elusive coins. From advanced features to user-friendly designs, we’ll highlight the key factors to consider when selecting the perfect detector for your coin hunting adventures. List of the Best Metal Detectors for Coin Hunting IMAGEPRODUCTRATING Minelab Equinox 800 Metal DetectorBest Choice 5/5 View on Amazonlabel Garrett ACE 400 Metal Detector 4.5/5 View on Amazonlabel Nokta The Legend Metal Detector 4.5/5 View on Amazonlabel Check out the thorough review of the best metal detectors for coin hunting below. 1. Minelab Equinox 800 Metal Detector This all-terrain, multi-purpose detector utilizes Minelab’s advanced Multi-IQ simultaneous multi-frequency technology, rendering single-frequency VLF detectors obsolete. Designed for both seasoned enthusiasts and beginners, the Equinox 800 features four detect modes (Park, Field, Beach, Gold) and six frequency options (Multi, 5kHz, 10kHz, 15kHz, 20kHz, 40kHz), making it adaptable to various target types and ground conditions. The detector is equipped with an EQX 11″ Double-D Smart Coil, wireless Bluetooth/apt-X low latency headphones, and a WM 08 wireless audio module, ensuring fast recovery speed and low-latency audio. Its lightweight, waterproof platform, combined with a robust adjustable armrest and multi-language screen protectors, enhances usability and comfort. The USB charging cable with magnetic connector facilitates easy recharging. Users appreciate the Equinox 800’s simplicity and effectiveness. The setup manual is comprehensive, enabling even a 10-year-old to operate it effortlessly. The detector’s high performance, combined with the included Pro Find 35 Pinpointer, carry bag, and finds pouch, makes it an exceptional value for both novice and experienced detectorists. Pros and Cons Pros: Multi-IQ Technology: Superior multi-frequency detection for varied targets and conditions. User-Friendly: Easy setup and operation, suitable for beginners. Versatile Detect Modes: Four modes for different environments (Park, Field, Beach, Gold). Wireless Audio: Includes Bluetooth headphones and WM 08 wireless module for low-latency audio. Comprehensive Bundle: Comes with Pro Find 35 Pinpointer, carry bag, and finds pouch. Cons: Complex Features: Advanced settings may overwhelm complete beginners. View On Amazon 2. Garrett ACE 400 Metal Detector This model features an 8.5″ x 11″ PROformance DD waterproof submersible search coil, providing versatility in various terrains, including underwater environments. With a higher frequency of 10 kHz, the ACE 400 enhances the detection of small targets, making it ideal for coin, jewelry, and relic hunting. The digital target ID and adjustable frequency settings ensure precise detection, while the Iron Audio and enhanced iron resolution features help to differentiate between valuable targets and trash. The package includes a Garrett Pro Pointer AT for accurate pinpointing, ClearSound headphones with in-line volume control, and a durable carry bag for easy transportation. Additionally, the electronic pinpointing and notch discrimination features, combined with five search modes and eight sensitivity/depth adjustments, offer a comprehensive and customizable detecting experience. Pros and Cons Pros: High Detection Frequency: 10 kHz frequency for enhanced target detection. Waterproof Coil: Submersible search coil for versatile use in various terrains. Advanced Features: Digital Target ID, Iron Audio, and enhanced iron resolution. Comprehensive Accessories: Includes Pro Pointer AT, headphones, and carry bag. User-Friendly: Easy to learn and use with adjustable settings. Cons: Size: Larger carry bag may be cumbersome for some users. View On Amazon 3. Nokta The Legend Metal Detector As Nokta’s first simultaneous multi-frequency metal detector, The Legend is designed to excel in diverse environments and for various target types. Featuring a robust IP68 waterproof rating, it can be fully submerged up to 10 feet, making it an excellent choice for underwater detection. This model is also optimized for gold prospecting, capable of identifying small gold nuggets in highly mineralized fields. The package includes a system box, Bluetooth aptX Low Latency headphones with a soft case, a USB charging/data cable, and a waterproof DD 12″ x 9″ LG30 coil. The Legend boasts a long battery life, providing up to 20 hours of continuous use on a single charge. This rechargeable lithium battery can be conveniently charged using any standard USB charger or power bank, ensuring cost savings and reducing battery waste. Customers praise the detector’s versatility and advanced features. The ease of use, combined with the high-tech rechargeable battery and the efficiency of simultaneous multi-frequency technology, positions The Legend as a top contender in the metal detecting market. Pros and Cons Pros: Multi-Frequency Technology: Adaptable for various targets and conditions. Waterproof: Fully submersible up to 10 feet. Gold Prospecting: Capable of detecting small gold nuggets in mineralized fields. Long Battery Life: Up to 20 hours on a single charge. Wireless Headphones: Includes Bluetooth aptX Low Latency headphones for seamless audio. Cons: Weight: Slightly heavier than some basic models. View On Amazon 4. Fisher F75 Multi-Purpose Metal Detector The Fisher F75 Multi-Purpose Metal Detector offers powerful performance with a trigger-actuated target pinpointing system that features variable audio pitch and a large LCD screen with a 0-99 numeric target identification display. This device excels in diverse environments, thanks to its double-filter discrimination modes that are perfect for searching in trashy areas. The magnetic mineralization bar graph and readout, along with the trigger-actuated FastGrab ground balance, enhance its efficiency in various soil conditions. The Fisher F75 includes a Double-D waterproof search coil, ensuring durability and versatility for beach hunting and other wet conditions. It also features a backlight for low-light hunting and non-volatile memory that saves your settings. With an operating time of over 40 hours on just four AA alkaline batteries, it offers low operating costs. Designed for coin shooting, relic hunting, beach hunting, and gold prospecting, this detector is a comprehensive solution for serious metal detecting enthusiasts. Pros and Cons Pros: Lightweight Design: Ergonomic and easy to handle for extended periods. Advanced Target ID: Large LCD screen with a 0-99 numeric target ID. Versatile Discrimination Modes: Double-filter modes for effective searching in trashy areas. Long Battery Life: Over 40 hours of operation on four AA batteries. Durable and Waterproof: Double-D search coil and optional rain cover for control and battery housing. Cons: Limited Waterproof Depth: Only the coil is waterproof, not the entire unit. View On Amazon 5. XP Deus II Metal Detector Equipped with a 9″ FMF search coil and an MI-6 pinpointer, this detector ensures exceptional performance and accuracy. The innovative XP patented radio protocol system allows seamless communication between the coil, remote control, headphones, and optional pinpointer, transmitting target signals without latency. This rapid signal transmission gives the DEUS II unmatched speed and precision. Designed to excel in all terrains, including underwater environments, the DEUS II employs Fast Multi-Frequency (FMF) technology. It is waterproof up to 66 feet (20 meters), making it ideal for both land and sea exploration. The detector includes a remote control with a hipmount case, wireless WS6 headphones with a storage case, and a telescopic stem for enhanced ergonomics. The power adapter and charging cable support all components, ensuring up to 25 hours of battery life depending on audio output settings. Constructed with durability in mind, the XP Deus II is lightweight and ergonomically designed for extended use. With 12 factory programs and 12 user programs, it offers versatility for various detecting scenarios. Manufactured in France, this detector comes with a five-year warranty, guaranteeing long-lasting reliability and performance. Pros and Cons Pros: Wireless Technology: Seamless communication between components without latency. Waterproof: Submersible up to 66 feet (20 meters) for underwater use. Multi-Frequency Detection: Fast Multi-Frequency technology ensures high accuracy and performance. Long Battery Life: Up to 25 hours of operation on a single charge. Versatile Programs: 12 factory and 12 user programs for diverse detecting conditions. Cons: Maintenance: Waterproof seals and components need regular checks. View On Amazon 6. Minelab Vanquish 540 Metal Detector Leveraging Minelab’s revolutionary Multi-IQ technology, this detector simultaneously employs five frequencies, enabling comprehensive searches across all metals and soil types. With the Vanquish 540, users do not need to manually select frequencies or ground balance; the device automatically adjusts settings based on soil conditions, ensuring optimal performance. This detector features four distinct modes—Park, Field, Beach, and a customizable mode—each tailored to different environments and target types. The pinpoint mode provides precise location detection, enhancing search accuracy. The 12″x9″ Double-D waterproof coil is ideal for underwater exploration and challenging terrains. Weighing only 2.8 pounds and collapsible to 30 inches, the Vanquish 540 is both lightweight and portable, making it easy to carry on any adventure. Its user-friendly interface, complete with a backlight for low-light conditions, allows for seamless operation. The detector also offers advanced audio control with automatic noise canceling, lag-free response, and ten volume settings. Included in the package are wired headphones and a rain cover, ensuring you’re equipped for any weather. Pros and Cons Pros: Multi-Frequency Technology: Employs five frequencies simultaneously for thorough searches. Ease of Use: Automatic frequency selection and ground balancing. Lightweight & Portable: Weighs 2.8 lbs and collapses to 30 inches. Versatile Search Modes: Four modes tailored to different environments. Advanced Audio Control: Noise canceling and ten volume settings. Cons: Wired Headphones: Less convenient compared to wireless options. View On Amazon 7. Nokta Simplex Ultra Waterproof Metal Detector Designed for both beginners and professionals, this detector features a fully carbon fiber shaft, providing durability and aesthetic appeal. The shaft retracts down to 25 inches, making it convenient for transport, storage, and diving. With a waterproof capability of up to 16 feet (5 meters), the Simplex Ultra is perfect for underwater exploration. This detector is lightweight, weighing only 2.6 pounds, ensuring ease of use for extended periods without fatigue. It includes a high-resolution color LCD screen that displays essential information clearly, and a user-friendly interface for effortless access to settings and adjustments. The Simplex Ultra also offers online firmware updates via USB, ensuring users can always have the latest features and improvements. Key features include easy operation with a turn-on-and-go design, vibration feedback upon target detection, and a backlit keypad and LCD with an LED flashlight for low-light conditions. The long battery life, rechargeable via USB, adds to its practicality and convenience. Pros and Cons Pros: Waterproof Depth: Operates up to 16 feet underwater. Durable Build: Fully carbon fiber shaft for enhanced durability. User-Friendly Interface: High-resolution color LCD and easy-to-use menu. Lightweight Design: Weighs only 2.6 pounds for prolonged use. Firmware Updates: Online updates keep the detector current with the latest features. Cons: Visibility Issues: LCD screen may be hard to read in bright sunlight. View On Amazon 8. Teknetics EuroTek PRO Metal Detector This detector offers a range of advanced features that enhance its usability and performance. The Iron Target Indicator is a standout, providing clear signals when iron is detected, regardless of the discrimination setting. This is complemented by the Fe Tone Variable Iron Discrimination, which allows users to set the volume of ferrous targets lower than non-ferrous targets, ensuring clarity and precision in target identification. Designed with ease of use in mind, the EuroTek PRO features a Motion Discrimination Mode and a no-motion Pinpoint Mode, aiding in accurate target recovery. Its lightweight and well-balanced construction make it comfortable for extended use. Additionally, the detector excels in iron-infested sites due to its fast recovery speed and excellent target separation. The turn-on-and-go functionality makes it accessible for beginners, while its robust performance satisfies more experienced users. Customers appreciate its ease of opening, high performance, and build quality, often highlighting it as an excellent entry-level metal detector. Pros and Cons Pros: Iron Target Indicator: Clearly signals the presence of iron. Adjustable Iron Audio: Customizable audio settings for ferrous and non-ferrous targets. Ease of Use: Turn-on-and-go functionality ideal for beginners. Lightweight Design: Comfortable for extended detecting sessions. Target Separation: Excels in iron-infested sites with fast recovery speed. Cons: Limited Coil Size: 8-inch coil may cover less ground per sweep. View On Amazon What Makes a Great Coin Metal Detector? When it comes to coin hunting, having the right metal detector can make a world of difference. A great coin metal detector should possess several key qualities that set it apart from the pack. First and foremost, sensitivity and discrimination are paramount. The best coin detectors have highly tuned circuits that can detect even the faintest signals from small, deeply buried targets like coins. At the same time, they should offer excellent discrimination capabilities to filter out unwanted trash items like bottle caps or pull tabs, allowing you to focus solely on potential coin strikes. Equally important is ground balance and mineralization handling. Coin hunting often takes place in highly mineralized soil conditions, which can cause lesser detectors to produce excessive noise and false signals. Top-tier coin detectors have advanced ground balancing features that adapt to these challenging environments, ensuring stable operation and accurate target identification. Another critical factor is target separation and identification. The ability to differentiate between multiple targets in close proximity and provide detailed target information (size, depth, conductivity) is a hallmark of a high-performance coin detector. This feature becomes invaluable when hunting in areas with high concentrations of buried objects. Durability and ergonomics also play a role in a great coin detector. These devices are frequently used in rugged outdoor conditions, so a sturdy, weatherproof construction is essential. Additionally, a well-designed control layout and lightweight, balanced form factor can make long hunting sessions more comfortable and productive. Finally, top coin detectors often come equipped with advanced features like multiple frequency selection, adjustable iron audio, and wireless headphone connectivity, offering users more control and customization options to suit their preferences and hunting environments. What Features Should I Look for in a Coin Metal Detector? When shopping for a coin metal detector, it’s crucial to consider the features that will enhance your hunting experience and success rate. While the specific features may vary across different models and manufacturers, several key attributes should be on your radar. Target Identification and Discrimination Look for detectors with advanced target identification systems that can accurately distinguish between various types of metal targets, such as coins, jewelry, and unwanted trash items. This feature is essential for maximizing your time and efficiency by focusing solely on potential coin finds. Additionally, adjustable discrimination settings allow you to fine-tune the detector’s response to different types of targets based on your preferences. Multiple Frequency Operation Many modern coin detectors offer the ability to operate on multiple frequencies, each with its own strengths and weaknesses. Higher frequencies are generally better for detecting smaller targets like coins, while lower frequencies excel at detecting larger, deeper targets. Having the option to switch between frequencies can be invaluable when hunting in different environments or for specific target types. Ground Balance and Mineralization Handling Coin hunting often takes place in areas with highly mineralized soil, which can cause interference and false signals. Look for detectors with advanced ground balance features that can automatically or manually compensate for these challenging conditions, ensuring stable operation and accurate target detection. Depth and Sensitivity The depth at which a detector can reliably detect coins is a crucial factor, particularly when hunting in areas that have been well-searched before. High-end coin detectors boast impressive depth capabilities, allowing you to uncover deeply buried treasures that others may have missed. Sensitivity settings also play a role, enabling you to fine-tune the detector’s responsiveness to faint signals. Waterproof and Weatherproof Construction Coin hunting can expose your equipment to various outdoor elements, such as rain, moisture, and dusty conditions. Investing in a detector with a waterproof and weatherproof design can protect your investment and ensure reliable operation in any environment. User-Friendly Controls and Displays Look for detectors with intuitive controls and clear displays that make it easy to navigate settings, interpret target information, and adjust configurations on the fly. Well-designed ergonomics and lightweight construction can also contribute to a more comfortable and enjoyable hunting experience. Additional Features Depending on your specific needs and budget, you may want to consider additional features like wireless headphone connectivity, adjustable iron audio, pinpoint mode, and compatibility with external search coils or accessories. How to Choose the Best Coin Metal Detector? Identify Your Hunting Grounds Before we dive into the nitty-gritty of metal detector specifications, let’s start by understanding your primary hunting grounds. Are you planning to scour beaches, parks, or perhaps historic sites teeming with buried treasures from bygone eras? Different environments demand different capabilities from your metal detector. For instance, if you’re venturing into highly mineralized soil conditions, you’ll need a detector with advanced ground balance features to eliminate interference and false signals. Frequency: The Key to Coin Hunting Success Undoubtedly, one of the most crucial factors to consider is the operating frequency of the metal detector. Generally, higher frequencies excel at detecting smaller targets like coins, while lower frequencies are better suited for larger, deeper objects. However, some detectors offer multi-frequency capabilities, allowing you to switch between settings based on your target preferences. Moreover, if you’re primarily interested in coin hunting, prioritize detectors with high-frequency options above 10 kHz, as these are optimized for pinpointing even the faintest signals from those elusive coin caches. Discrimination: Separating Treasure from Trash Imagine the frustration of digging up countless bottle caps and pull tabs, only to find no coins in sight. That’s where discrimination comes into play. Top-notch coin detectors boast advanced discrimination capabilities, enabling you to filter out unwanted trash items and focus solely on potential coin strikes. Look for detectors with adjustable discrimination settings, allowing you to fine-tune the device’s response based on your preferences and hunting environment. Target Identification and Separation In addition to discrimination, target identification and separation are invaluable features for successful coin hunting. These capabilities allow your detector to differentiate between multiple targets in close proximity and provide detailed information about each one, such as size, depth, and conductivity. This invaluable feature becomes a game-changer when hunting in areas with high concentrations of buried objects, ensuring you don’t miss out on any hidden treasures. Depth and Sensitivity: Leave No Coin Unturned Let’s face it, the thrill of coin hunting lies in uncovering those deeply buried treasures that others may have missed. That’s why depth and sensitivity are paramount considerations. Look for detectors with impressive depth capabilities, allowing you to probe deeper into the earth and uncover coins that have eluded even the most seasoned hunters. Simultaneously, adjustable sensitivity settings enable you to fine-tune the detector’s responsiveness to faint signals, ensuring that even the smallest coin doesn’t slip through the cracks. Durability and Ergonomics: Built for Adventure Coin hunting often takes place in rugged outdoor environments, subjecting your equipment to various elements and challenges. Therefore, investing in a durable, weatherproof metal detector is crucial to ensure reliable performance and longevity. Look for detectors with sturdy construction, waterproof housing, and robust designs that can withstand the rigors of your treasure-seeking escapades. Additionally, ergonomics play a significant role in your overall hunting experience. Well-designed control layouts, lightweight construction, and balanced form factors can make extended hunting sessions more comfortable, reducing fatigue and maximizing your productivity. Advanced Features: Elevate Your Coin Hunting Game While the core features mentioned above are essential, many modern metal detectors offer advanced capabilities that can take your coin hunting game to new heights. Wireless headphone connectivity, adjustable iron audio, and pinpoint modes are just a few examples of features that can streamline your hunting process and enhance your overall experience. Moreover, some detectors even come with compatibility for external search coils or accessories, allowing you to further customize and optimize your setup for specific hunting conditions or target types. Where Are the Best Places to Use a Coin Metal Detector? When it comes to coin hunting with a metal detector, choosing the right location can make all the difference. While coins can be found in various settings, certain places tend to yield more promising results than others. Here are some of the best places to consider for your next coin shooting adventure: Public Parks and Recreational Areas: Parks, playgrounds, and other public spaces are often treasure troves for coin hunters. These high-traffic areas have seen countless people passing through, increasing the likelihood of lost coins being left behind. Benches, picnic areas, and the surrounding grassy areas are prime hunting grounds. However, be sure to obtain any necessary permits and follow local regulations. Beaches and Swimming Areas: Coins frequently fall out of pockets or get lost in the sand at beaches and swimming holes. The wet conditions can help preserve coins, making them easier to detect. Focus your search on areas around beach entrances, concession stands, and anywhere people tend to congregate or change clothes. Historic Sites and Ghost Towns: Areas with a rich history often hold hidden treasures from bygone eras. Ghost towns, old homesteads, and sites of former settlements can yield valuable coin finds from the past. However, it’s essential to obtain permission and follow all relevant laws and regulations when hunting on historical grounds. Fairgrounds and Event Venues: Fairs, carnivals, and outdoor event venues are prime locations for lost coins. People often drop change while enjoying rides, games, and concessions. Be sure to get permission from the event organizers before prospecting these areas. Sports Fields and Stadiums: Coins can easily slip out of pockets during athletic activities or while cheering on a favorite team. Check around bleachers, dugouts, and areas where spectators gather at sports fields, stadiums, and arenas. School Yards and Campgrounds: Children and families often frequent these locations, increasing the chances of dropped coins. Playgrounds, picnic areas, and camping sites are all potential hotspots for coin finds. Old Homesteads and Farms: If you have access to private property with a history of habitation, old homesteads and farms can be goldmines for coin hunters. Concentrate your search around former building sites, barns, and areas where daily activities took place. Frequently Asked Questions when Picking the Best Metal Detectors for Coin Q1. What is the best frequency for coin hunting? The best frequency for coin hunting is generally considered to be in the high range, typically above 10 kHz. Higher frequencies excel at detecting smaller targets like coins due to their shorter wavelengths. Many top coin metal detectors offer multiple frequency options, allowing you to switch between high and low frequencies depending on your target preferences. Q2. What is target separation, and why is it important for coin hunting? Target separation, also known as target ID or target identification, is a feature that allows your metal detector to distinguish between multiple targets in close proximity and provide detailed information about each one, such as size, depth, and conductivity. This feature is crucial for coin hunting because it helps you differentiate between coins and other metallic objects, ensuring you don’t waste time digging up unwanted items. Q3. How important is ground balance for coin hunting? Ground balance is an essential feature for coin hunting, especially in areas with highly mineralized soil. Mineralized soil can cause interference and false signals, making it difficult to detect coins accurately. Advanced ground balance features allow your metal detector to compensate for these challenging conditions, ensuring stable operation and accurate target identification. Look for detectors with automatic or manual ground balance capabilities. Q4. Are waterproof and weatherproof metal detectors necessary for coin hunting? While not absolutely necessary, waterproof and weatherproof metal detectors are highly recommended for coin hunting. Coin hunting often takes place in outdoor environments, exposing your equipment to various elements like rain, moisture, and dusty conditions. A waterproof and weatherproof design protects your investment and ensures reliable operation in any environment. Q5. What are the top-rated coin metal detectors on the market? Some of the top-rated coin metal detectors on the market include the Minelab Equinox series, Garrett AT Pro, Nokta Makro Simplex+, XP Deus, and Teknetics EuroTek Pro. These detectors are known for their high performance, advanced features, and specialized capabilities for coin hunting. Q6. How much should I expect to pay for a quality coin metal detector? The cost of a quality coin metal detector can vary widely depending on the brand, features, and capabilities. Entry-level coin detectors may cost between $200 to $500, while mid-range models can range from $500 to $1,000. High-end, top-of-the-line coin detectors from reputable brands can cost anywhere from $1,000 to $2,500 or more. Q7. What accessories should I consider for coin hunting? Some useful accessories for coin hunting include headphones (wired or wireless) for better audio feedback, pinpointer tools for precisely locating targets, diggers or hand trowels for efficient digging, and a pouch or apron for carrying your finds. Additionally, you may want to invest in a quality scoop or sand scoop if you plan to hunt in sandy or loose soil environments. Q8. Are there any specific techniques or tips for successful coin hunting? Yes, there are several techniques and tips that can improve your coin hunting success rate. These include: Researching and selecting high-potential areas like parks, beaches, fairgrounds, and historic sites. Scanning in overlapping patterns to ensure complete coverage. Using the correct coil size and configuration for your target type (smaller coils for coin hunting). Adjusting your detector’s settings based on the hunting environment and target preferences. Being patient and methodical in your search patterns. Respecting private property and obtaining necessary permissions. Q9. Can I use my coin metal detector for other types of metal detecting? While coin metal detectors are optimized for finding coins, many of them can be used for other types of metal detecting as well. With adjustable settings and the ability to switch frequencies, a quality coin detector can also be effective for locating jewelry, relics, or other metallic objects. However, for dedicated relic or treasure hunting, specialized detectors may be more suitable. Q10. How often should I replace or upgrade my coin metal detector? The lifespan and need for replacement or upgrade can vary depending on the quality and usage of your coin metal detector. Generally, entry-level detectors may need to be replaced every 3-5 years, while mid-range and high-end models can last 5-10 years or more with proper care and maintenance. If you find that your detector is no longer meeting your needs or lacks advanced features, an upgrade may be warranted to improve your coin hunting experience. Final Thoughts In conclusion, investing in the right metal detector can significantly enhance your coin hunting experience. Whether you’re searching for rare collectibles or simply enjoying the thrill of uncovering hidden treasures, the detectors featured in this guide offer a range of options to suit every budget and skill level. Remember to consider factors such as frequency, discrimination, depth detection, and ease of use when making your decision. With the right detector in hand, you’ll be well-equipped to embark on countless coin hunting expeditions and uncover a wealth of fascinating finds. Enjoyed this guide of the best metal detectors for coins? Then be sure to check out our other metal detector guides. Best Metal Detectors for Beginners Best Metal Detectors for Beach Best Metal Detectors for Kids Best Metal Detectors for Depth Best Metal Detector Pinpointers Metal Detector for Coin CoinDetectorMetalMetal Detector