The COMPACtenna LMR-I Is A Compact High Performance Ham Radio/Commercial Land Mobile Radio Antenna. Perfect for Public Service-Safety Govt, Commercial-Business, Marine, GMRS and MURS use.
Measures in at only 9” Long x 1.5” Diameter and features a reliable leaf spring style NMO connector on antenna for standard center-stud style NMO mounts.
Optimized for 3 Wide Frequency Bands:
- VHF 136 - 174 MHz
- UHF 378 - 512 MHz
- 750 - 960 MHz
Performs well in both Digital & Analog modes for any of these agencies: Ham Radio, Police, Fire, Sheriff, Emergency Medical, State Highway Patrol, Homeland Security, U.S. Federal, Military, Business-Commercial, Marine, GMRS and MURS
The LMR-I antenna makes a great fit for full spectrum as well as their mono-band Motorola, L3Harris, EFJohnson, Raytheon, and TAIT radios.
Each Antenna Manufactured is Precisely Tested and Tuned before shipment.
High Performance Low Profile Vehicle Antenna. The LMR-I is also excellent for Base Station / Repeater use particularly with installations below 100-150’ above ground / HAAT - where Non-Line-of-Sight (NLOS) Propagation is more substantial
Antenna Type: Unique Electric/Magnetic Field Diversity Science & Technology Patented Design - Patent No. US 9,407,001
- Special Design Construct of spiraled and cylindrical metal sheeting including ‘extended flat monofilar spiral Tesla-like coils’
- All resistance, inductance and capacitance (matching) is efficiently done by the physical metallic geometric form of the antenna itself, as opposed to internal or external (lossy) components of other designs.
- “Magnetic Field Resonator”: This built-in resonating matching system is an effectual component of the electromagnetic E & H fields production, resulting in better performance than expected for such a small antenna.
- With a particularly strong magnetic near field, proximity noise is reduced. Resulting diverse effective electromagnetic fields (elliptical polarization and phase diversity) as well as broad elevation coordinate signal pattern provides stabilized signals in our common Non-Line of Sight environments, with temperature and humidity inversion pathways & tropospheric propagation, and satellite communications, further enhancing performance in our world of (dynamic) obstructions, mitigating signal drops, reducing flutter, and increasing reliable range.
Maximum Power Ratings:
- Vehicle & Base Station Operation: 110 Watts VHF; 75 Watts at higher frequencies
- At maximum power, duty cycle is 50%: Up to 1 minute transmit in any 2-minute period under normal use and conditions
- With longer transmissions, higher duty cycles, incl. with such as digital communications, decrease power, provide ‘cooling-off’ periods.
Gain: Nominal 5(+) dB-MEG
- Due to diverse EM Fields of the Magnetic Field Resonator, performance is greater than predicted based on (singular polarization/peak gain) field-range/anechoic chamber gain studies alone, in NLOS (Non-Line-Of-Sight) environments which is the world we live in.
(V)SWR: nominal <2:1 [MHz] 148-174, 400-512MHz, 750-960MHz; <2.5:1 144-148, 390-400; <3:1 136-144, 378-390
- Best (V)SWR’s especially on VHF frequencies are generally seen when mounting at upper corners of a vehicle.
- Signal pattern is substantially omnidirectional at corner locations, utilizing the downward/sloping metal of vehicle as counterpoise
- METAL Ground Plane Vehicle Counterpoise - Apply antenna mount to metal with good (clean) ground connection; Magnet mount type provides capacitive coupling, the ‘Flat’ style often provides best SWR’s
Mount Types: see COMPACtenna.com
- (V)SWR’s can vary with size & shape of vehicle & accessories; (V)SWR’s seen by the radio are often lower due to feed-line attenuation.
- Always check SWR; operate only per transmitter/amplifier specifications.
Base Station Antenna:
This revolutionary antenna may also be used as a high performance compact base station/repeater antenna by utilizing the COMPACtenna CompacCounterpoise-NFemale, a heavy duty ground plane counterpoise radial kit optimized for gain, pattern and SWR on VHF and UHF frequencies; (V)SWR: nominal <2:1 150-162MHz, 430-470MHz, 750-960MHz.
Each Antenna is quality checked and tuned. Keep antenna and mount contacts clean. Fine grit emery cloth, for example, may remove oxidation. Thread lengths and center contact heights of different NMO mounts vary; make certain of good contact by antenna leaf spring - at times pulling the antenna leaf spring downward slightly is helpful before screwing antenna onto mount, especially if changing to another mount. Removing, re-attaching antenna repeatedly is not recommended; dedicated vehicle & base station systems are best. Use lube provided for NMO threads, center contacts and gasket, hand tighten securely. Brushless car washes, hand washing reduce risk of antenna/mounting damage. The antenna side screw is an added measure for secure physical integrity; it is to be left alone. See www.COMPACtenna.com for further information. [Design and specifications subject to change without notice.]
