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Professional antennas in MF, VHF, UHF and SHF frequency range for military applications, civil-professional market, mobile communications, radioamateurs and antennas for special applications - EMC, radiomonitoring, etc.

KF4SCI picture of a project for a VHF UHF jpole antenna working on 220 and 440 MHz.

A vhf moxon antenna plan

Create - Reliable antenna and antenna rotators from japan. Manufacturer of amateur radio products, HF VHF UHF antennas, antnena towers, antenna rotors, HF Log Periodic Antennas, VHF UHF wideband amateur radio antennas

Comparison chart of most popular VHF UHF amateur radio transceivers

VHF Antenna in a lunchbox. The magnetic loop on two metres band Lloyd Butler VK5BR

Full line of VHF/UHF handheld and and mobile transceivers and accessories

CB radios, VHF transceivers, scanners antennas and accessories

A Portable VHF-UHF Roll-up J-pole Antennam that resonates on both bands but actually performs as a half wave radiator on both bands

Demonstrates the construction of a **homebrew spectrum analyzer** designed by Wes Hayward, W7ZOI, and Terry White, K7TAU, enabling radio amateurs to build a capable test instrument without significant expense. The resource details a _double-conversion superheterodyne_ circuit, employing intermediate frequencies of 110 MHz and 10 MHz, and covers essential blocks such as the time base, logarithmic amplifier, resolution filters, and local oscillators. It highlights the use of hybrid and monolithic ICs, including mixers, amplifiers, and VCOs, to simplify construction while maintaining performance. The design supports useful measurements in the 50 kHz to 70 MHz range, with methods outlined for extending capabilities into VHF and UHF. The authors emphasize that this analyzer, while simple to build, is intended for serious measurements, requiring careful control of signal levels to avoid spurious responses. It uses an oscilloscope for display, with specific instructions for calibration and adjustment of various stages, including the log amplifier and IF gain. The guide provides detailed schematics and component lists for each section, such as the 110 MHz triple-tuned band-pass filter, which achieved **90 dB** image rejection, a significant improvement over double-tuned circuits. Practical advice on alignment and troubleshooting is included, drawing on the authors' extensive experience in RF circuit design.

Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.

manufacturer of VHF and microwave antennas and related products, from 50 MHz through 10 GHz

Buildin a VHF Jpole antenna with detailed pictures

Tuning control of the Yaesu FT-736R multiband VHF/UHF transceiver.

UK reseller for HF VHF UHF

A VHF / UHF J-pole vertical antenna de ON6MU

The AMers nets from HF to VHF

A VHF Quad antenna for teh two meters band in italian

Well documented Amateur Radio HF/VHF antenna projects, high power Russian GS35B RF amplifiers, mobile RFI solutions, related accessories, vintage radios, Six meter equipment, and useful techniques by K8CU are inside.

Reccomendations and tips for VHF-UHF operation

Elelement yagi beam antenna for 2 meters band by ON6MU

N5IW ideas to build your own antenna in a restricted lot, or a stealth antenna. Includes PPT files of HF and VHF stealth antennas.

Looking for Hams that want to experiment on VHF/UHF PSK/digital modes

Arrow-Style VHF/UHF portable satellite antenna by VE2ZAZ

Maidenhead grid maps for VHF/UHF, These maps make excellent wallpaper for your contest setup.

A model of a Guanella 1:1 VHF choke balun using a FT140-61 core

Catalogs over 9,300 radio transmissions heard within Finland, providing a detailed frequency database for Finnish radio enthusiasts. The resource lists frequencies for various services, including maritime VHF channel 16 at **156.800 MHz**, RHA68 channel 16 at 71.100 MHz, and _MIL AIR_ frequencies like 251.100 MHz. It also documents air traffic control frequencies, such as 123.775 MHz for Area Control and 127.000 MHz for Approach Control, alongside frequencies for Finnish Air Force operations at 140.550 MHz. The database includes entries for commercial shared channels at 170.450 MHz and 458.250 MHz, as well as specific local business frequencies like 443.125 MHz for Sale Merimasku. Shortwave broadcast entries are also present, noting stations like BBC at 6.035 MHz from Tashkent and AIR Akashvani Ext.Sce at 11.900 MHz from Bangalore. The site organizes its extensive listings by categories such as "Liikenne" (Traffic) with 2397 entries, "Radioamatoori" (Amateur Radio) with 781 entries, and "Yle" (General) with 2305 entries. The database was last updated on 26.2.2024, reflecting ongoing maintenance and additions to its comprehensive collection of Finnish radio spectrum data.

This blog is about utility and military monitoring in the HF/VHF/UHF range.

VHF power amplifiers made in germany

Enables out-of-band transmit for 1.6 MHz to 54 MHz, Improved VHF recieve mod, other band expansions

VHF, UHF page, technical articles, projects, datasheets

146MHz 5/8 ground plane tower mounted antenna. The antenna was largely based information and analysis provided by the RSGB's. VHF UHF Manual, fourth edition by G.R.Jessop, G6JP

A Versatile Innovative Portable Multi-band Tunable Antenna can work HF VHF and UHF ideal as portable or balcony antenna

A listing of 2m SSB nets around the US.

ON6MU optimized 6/9 element vhf yagui antenna with antenna schematic plan and pictures of homebrewed samples.

This VHF 145 MHz antenna is easy to build and with no radials. It shows equal gain of 5/8 lambda. It is light weight, you can hang it somewhere (on a tree may be) and work.

Electronic circuit and components layout fot this VHF Preamp

A portable dualband dipole robust and compact antenna usable for horizontal and vertical polarisation by ON6MU

A project of VHF regenerative receiver by VK2ZAY

Wideband VHF/UHF/SHF monolithic PreAmp based on MARx-series by ON6MU

2 meters band VHF dipole with gamma match system

Notes on homebrewing antennas by Chris G4CYA, from gamma matching, to phasing antennas, splitters and combiners, baluns and measuring techniques.

Dual Band VHF/UHF Slim Jim Antenna project

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

A full line of single-channel synthesized and crystal controlled vhf and uhf fm receivers. Great for repeaters, telemetry, and control applications.

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

VU2RAR basic VHF power amplifier suitable for 144-146 Mhz output power can vary from 3 to 25 Watts.

Constructing a Lindenblad antenna for 137MHz NOAA satellite reception involves specific design considerations for optimal performance. The resource details the use of 4mm galvanised steel fencing wire, 300-ohm television ribbon cable, and wood/plastic components for the antenna structure. Key dimensions for a 137.58MHz-resonant antenna are provided, derived from the ARRL Satellite Handbook, specifying s, l, w, and d as 42, 926, 893, and 654mm respectively. The antenna is designed for Right Hand Circularly Polarised (RHCP) signals, requiring the four folded dipole elements to be tilted clockwise by 30 degrees. A significant aspect covered is impedance matching between the antenna's 75-ohm impedance and a typical 50-ohm receiver input. A twelfth-wave matching transformer, constructed from 117mm sections of 50-ohm RG-58 and 75-ohm RG-59 coax with a 0.66 velocity factor, is described. The article also addresses coaxial cable and connector selection, recommending 75-ohm Type-N connectors for RG-6 cable in professional setups and F56/F59 connectors for general use, while strongly advising against PL-259/SO-259 connectors for VHF. Strategies for mitigating Radio Frequency Interference (RFI) are discussed, including antenna placement to shield from local TV transmitters and the use of commercial or DIY band-pass filters, such as cavity resonators or helical notch filters, along with ferrite chokes on coaxial cables. Antenna orientation is explored, noting the Lindenblad's 'cone of silence' directly overhead and its maximized sensitivity towards the horizon. An experimental vertical tilt of 90 degrees is presented as a method to improve overhead reception and reduce interference from strong horizontal signals, particularly relevant in high RFI environments like the Siding Spring Observatory site.

This halo antenna was built to have an omnidirectional coverage while working in VHF contests.

SDR Receiver a compact high performance HF software defined radio receiver designed to be used in fixed or portable stations. Version 2 of the receiver is now available. It now has an RF pre-amplifier using a power MOSFET and other revisions to improve it's performance both as a stand alone receiver and as an IF panadaptor with HF and VHF transceivers.