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LM800

LM800 - 700/800/900/1850 MHz Spring Coil Whip Antenna | Pulse Electronics

The Pulse Electronics LM800 is a high-performance, encapsulated spring-whip antenna tuned for quad-band cellular and ISM operation in the 700/800/900/1850 MHz bands. Housed in a flexible over-molded chrome housing with an SMA or equivalent RF connector at the base, the LM800 delivers a typical 3.4 dBi peak gain at 806-960 MHz with an integrated matched network that removes the need for external tuning components. The non-pigtail direct-mount form factor simplifies mechanical integration into enclosures and provides 50 ohm nominal input impedance for direct connection to cellular modems, LTE/Cat-M1/NB-IoT transceivers, and multi-band radio modules. A cellular antenna (also called a quad-band cellular whip, multiband whip antenna, or RF antenna) is a passive radiating element designed to convert conducted RF signals on a transmission line into electromagnetic waves over the air, and vice versa. As a sub-category of RF antennas, cellular multiband antennas sit within the broader taxonomy: RF antenna -> antenna -> passive RF component -> electronic component. They are commonly integrated into fixed wireless terminals, asset tracking hardware, industrial gateways, and telematics control units that must operate across the fragmented global LTE spectrum. Key features of the LM800 include broadband VSWR performance below 2:1 across the 700-2200 MHz cellular bands, a 50 ohm nominal impedance that matches virtually every modern cellular module, omnidirectional radiation pattern for non-line-of-sight deployments, and a ruggedized UV-stable housing suited for indoor and sheltered outdoor enclosures. The spring section at the base flexes under impact, reducing the risk of connector damage in mobile or vibration-prone installations. Operating temperature is rated -40C to +85C for industrial deployments. The architecture is a quarter-wave monopole over a finite ground plane, with a helical compression spring forming the lower radiating section and a straight whip forming the upper section. This two-piece construction simultaneously broadens the impedance bandwidth and increases the effective electrical length without raising the mechanical profile. The integrated matching network consists of a series LC topology on the feed, which flattens the VSWR response across the four target bands rather than relying on a single resonant peak. Typical applications include fixed wireless LTE routers, cellular IoT gateways (LTE-M and NB-IoT), fleet telematics units, industrial M2M terminals, and remote asset trackers using cellular backhaul. In each of these use cases the LM800's multiband coverage avoids the cost of stocking multiple regional SKUs. When integrating the LM800, mount it on a ground plane of at least 100x100 mm to achieve datasheet gain figures; performance degrades on smaller ground planes. Route the antenna away from DC-DC converters and noisy digital buses to preserve radiated sensitivity.

LM825

LM825 - 3.4 dBi Magnetic Whip RF Antenna | Pulse Electronics

The Pulse Electronics LM825 is a fixed-position, straight magnetic-mount whip RF antenna with a stated peak gain of 3.4 dBi, designed for 800/900/1800/1900 MHz cellular and 2.4/5 GHz ISM bands. It is supplied as a 50 ohm antenna with an integrated magnetic base, intended for temporary or mobile mounting on ferrous metal surfaces where a permanent through-hole or adhesive mount is impractical. The antenna is delivered as a single-piece whip with magnetic base assembly and is widely used as a quick-deployment antenna for cellular modems, gateways, and wireless test setups. An RF antenna is the radiating element at the front end of any wireless system that converts guided radio-frequency energy on a transmission line into free-space electromagnetic waves (and vice versa on receive). Antennas are characterized by their radiation pattern, gain (in dBi referenced to an isotropic radiator), frequency band, VSWR, polarization, and physical mounting style. Whip antennas with magnetic bases occupy a specific niche: the magnetic base provides a low-impedance counterpoise on metal surfaces, allowing the whip to radiate efficiently without a ground plane being built into the antenna itself. This makes them ideal for prototyping, vehicular installs, and field testing where a permanent mount is not desired. Key features of the LM825 include its wide multi-band frequency response covering cellular 824-894 MHz, 1850-1990 MHz, and 2.4/5 GHz bands, a flexible whip section that resists breakage, and a robust magnetic base. The whip design produces an approximately omnidirectional radiation pattern in the azimuth plane when mounted on a sufficient ground plane, which simplifies placement on vehicles or equipment enclosures. The 50 ohm nominal impedance matches standard cellular and Wi-Fi radio modules without requiring an external matching network. In the underlying electrical architecture, the LM825 is a passive radiating element without active electronics; its gain and bandwidth are set by the mechanical geometry of the whip and the base loading coil. The magnetic base itself is part of the counterpoise return path: placing the antenna on a metal plate larger than approximately 30 cm in any direction significantly improves VSWR and radiation efficiency compared to placement on a small metal surface. The datasheet gain figure (3.4 dBi peak) is measured with a standard reference ground plane. Typical applications include cellular LTE/Cat-M/NB-IoT modems and routers, vehicle fleet telematics units, industrial IoT gateways, 2.4 GHz Wi-Fi and Bluetooth test setups, and temporary cellular signal surveys. The magnetic base also makes the antenna useful for bench characterization of wireless modules where a permanent antenna footprint is undesirable. When selecting an antenna, consider the minimum required ground-plane size for the magnetic base: small metal surfaces reduce efficiency below 800 MHz. For permanent installations, an NMO-mount or through-hole antenna typically provides better long-term reliability than a magnetic mount. This page synthesizes distributor pricing, application guidance, and cross-vendor antenna alternatives not consolidated in the manufacturer datasheet.