{"product_id":"atr-fsm-0-5mhz-5ghz-wide-range-handheld-field-strength-meter-support-4-display-modes-with-black-3d-printed-shell","title":"ATR-FSM 0.5MHz-5GHz Wide-Range Handheld Field Strength Meter Support 4 Display Modes with Shell","description":"\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003cbr\u003e\u003cspan\u003e- Wide Dynamic Range: Built-in hardware attenuation (~20x) and gain (~20x) switching. Measures from -70dBm to +50dBm without saturation or distortion, covering milliwatt UHF devices to tens-of-watt transmission systems.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Broad Frequency Coverage: Frequency range from 0.5MHz to 5GHz. Compatible with various antennas (default 433MHz antenna included) for measuring everything from LF magnetic fields to microwave bands, including power line magnetic fields.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Four Display Modes: Graphical menu with four modes: Digital mode (precise readings), Needle mode (signal fluctuation), Graph mode (trend observation), and Recorder mode (max value logging). Locks instantaneous peaks for antenna tuning and interference hunting.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Full-Color HD Screen: 1.8-inch full-color display (160x128 pixels) with Day mode (outdoor high brightness) and Night mode (soft lighting). Screen orientation freely switchable between landscape and portrait.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Compact \u0026amp; Long Battery Life: Highly integrated pocket-sized design. Built-in 800mAh battery supports half a day of continuous testing, ideal for tower-top debugging and field surveys.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- USB-C Charging \u0026amp; Firmware Updates: Standard USB Type-C interface supports 5V\/1A charging with most phone chargers and power banks. Also serves as a firmware upgrade port - connect to a PC without a dedicated programmer.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eSpecifications:\u003c\/b\u003e\u003cbr\u003e\u003cspan\u003e- Frequency range: 0.5MHz - 5GHz\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Measuring range: -70dBm to +50dBm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Range switch: ~20x attenuation \/ ~20x gain\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Main control: ESP32 240MHz\/ADC 16-bit high resolution\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Antenna interface: SMA-KE\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Product size: 6.4 x 4 x 1.6cm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Net weight: 45g\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Battery: 800mAH\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Charging: USB Type-C 5C\/1A (it does not support fast charging)\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003e- Display screen: 1.8-inch high quality full color display\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003ePackage Included:\u003c\/b\u003e\u003cbr\u003e\u003cspan\u003e- 1 x Field Strength Meter\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eFAQ:\u003c\/b\u003e\u003cbr\u003e\u003cspan\u003eQ: What is the input impedance of the ATR-FSM?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: The input impedance of the ATR-FSM varies with frequency and the characteristics of the signal source being measured. This is an intentional design choice to achieve wider electromagnetic environment compatibility. The device can effectively measure various non-50Ω signal sources, including 75Ω antennas, USB cable radiation, AC power line electromagnetic leakage, and more, providing greater field adaptability and versatility.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eQ: Is the ATR-FSM a relative measurement device or an absolute measurement device?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: The ATR-FSM is a professional relative field strength comparison tool. It is ideal for comparing the relative impact on signal strength between different antennas, filters, or device layouts under identical test conditions. For example, you can take a baseline measurement using a reference antenna, then switch to Antenna B for measurement, and directly compare the field strength differences between the two. The built-in data logging feature automates this process, eliminating the need for manual transcription.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eQ: What is the measurement principle of the ATR-FSM?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: The ATR-FSM uses a classic architecture of a detector diode plus a high-precision ADC (ADS1115, 16-bit), a principle widely used in professional field strength detection solutions. The process is as follows: the RF signal induced by the antenna is converted to DC voltage through the detector circuit, the ADS1115 directly measures this voltage to obtain a true signal response value, and the device performs conversion display according to the user's selected display mode. Advanced users can read the raw ADC voltage directly in the [Config - Test] menu.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eQ: What is the detection resolution of the ATR-FSM?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: The ATR-FSM features a 16-bit ADC (ADS1115), capable of detecting extremely small voltage changes. Combined with two physical ranges (20x gain \/ 20x attenuation), the device covers a wide dynamic range from very weak ambient noise to signals from tens-of-watts transmitters. In practical use, even slight adjustments to antenna position or orientation result in clear reading changes on the screen, making it ideal for fine comparison of performance differences between different antennas or for locating electromagnetic leakage points.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eQ: How are the gain and attenuation ranges of the ATR-FSM designed?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: The device features two physical ranges, both with a gain\/attenuation factor of 20x, a value selected through extensive practical testing as the 'golden factor'. Gain mode (20x) effectively amplifies weak induced signals while preventing ambient background noise from saturating the reading. Attenuation mode (1\/20x) provides appropriate signal reduction when measuring stronger signals, keeping the reading in the linear region. This design ensures broad coverage from tiny signals to strong transmitter signals.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eQ: What are the unique advantages of the ATR-FSM?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: Compared to traditional mechanical meter field strength meters or simple solutions requiring an external multimeter, the ATR-FSM offers core advantages including pocket size for portability, built-in data logging that automatically samples and records signal strength curves without manual transcription, easy comparison of field strength differences between different antennas or device layouts, a large screen displaying multiple units clearly, and accessible raw data. It is a practical tool designed for amateur radio enthusiasts, electronics engineers, and field test personnel.\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan\u003eQ: How to properly use the ATR-FSM for antenna comparison?\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eA: The following steps are recommended: keep the transmitter, test distance, and surrounding environment fixed; take a measurement using a reference antenna and record the baseline data; switch to Antenna B (the antenna under test) and take a second measurement at the exact same position and distance; compare the relative difference between the two measurement results. The antenna with the higher reading has better coupling efficiency under that test condition. This method effectively offsets environmental fluctuations and impedance mismatch effects, yielding meaningful comparison conclusions.\u003c\/span\u003e\u003c\/p\u003e","brand":"Thanksbuyer","offers":[{"title":"Black 3D-Printed Shell","offer_id":41173311520817,"sku":"103613","price":35.81,"currency_code":"USD","in_stock":true},{"title":"Black CNC Metal Shell","offer_id":41173311553585,"sku":"103614","price":47.47,"currency_code":"USD","in_stock":true},{"title":"Silvery CNC Metal Shell","offer_id":41173311586353,"sku":"103615","price":47.47,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0578\/4790\/6353\/files\/103613-1.jpg?v=1786585833","url":"https:\/\/www.thanksbuyer.com\/it\/products\/atr-fsm-0-5mhz-5ghz-wide-range-handheld-field-strength-meter-support-4-display-modes-with-black-3d-printed-shell","provider":"Thanksbuyer Online,SDR Radio, Testers and Measurement devices, Astronomy products,  Audio Amplifer and Decoders","version":"1.0","type":"link"}