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Build your own antenna for the 23cm band ( 1250Mhz - 1280Mc ) using some aluminium and this simple design.

A 6 elements VHF Yagi antenna designed with YAGIMAX 3 and made by SV1XY with excellent results on local and satellites contacts like UO-14 and AO-27

The QM7 antenna is a simple 7 elements Yagi with 3.70 m boom length for the lower 144 MHz SSB/MGM band, used it mainly for Sporadic-E and MS contacts. It exhibits a forward gain of 11.35 dBd; i.e. 13.5 dB forward gain over the isotropic radiator, while the F/R is about 12.5 dB

AM/FM/CW QRP RF Power Amplifier for the HF 10 or 11 meterband (28MHz/27MHz)

This is an antenna that author just built. Was intend for receiving the AO-27 downlink (at 436.800 +/- doppler). It is built with right hand circular polarization, and the gain is supposed to be in the neighborhood of 3 DB.

A project for a balcony antenna that works on 7 10 14 MHz made by 2 PVC tubes coiled with insulated copper wire, a solution for restricted lots.

The Grid Yagi (or Grid Quad) is a high performance yagi antenna that can be built with readily obtainable inexpensive materials. Described here is a 6 element 2 meter version with a boom length of about 1 wavelength, shown

IC-2720H it will receive fine on 220MHz amateur band, but will NOT transmit there

A moxon antenna for 11 meter band, suitable for 27 Mhz and 28 Mhz

CQDX11.com serves as a vital hub for Citizens Band (CB) radio operators, particularly those interested in the 27 MHz band. The site offers a wealth of information on CB radio models, modifications, and antennas, catering to both beginners and seasoned DXers. Users can explore various resources, including a logbook for tracking contacts, forums for community interaction, and guides on equipment and techniques for effective communication. In addition to technical resources, CQDX11.com emphasizes the social aspect of CB radio, providing a platform for users to share experiences, tips, and engage in real-time chat. The site also features a section dedicated to CB radio news and updates, ensuring operators stay informed about the latest trends and developments in the CB community. Whether you're looking to enhance your setup or connect with fellow enthusiasts, CQDX11.com is an essential destination for all things related to CB radio.

Building an omnidirectionnal antenna for the 23 cm band, 1240 - 1270 Mhz

Dutch web site dedicated to freebanding on 27 mhz.

A 27-28 Mhz quad loop antenna by Bernard Mourot F6BCU in french

Operates the VHF 2 Meter KR9RK repeater on 147.270 MHz

A Yagi-Mag antenna for the 4 meters band with NEC and MMANA files plans and pictures

On 7.274 MHz since 1955

How to convert the ICOM VHD base station IC-275D to 275H 100W 144-148Mhz

Yaesu FT-7800R dual band 2m/440Mhz mobile radio review

28,227.5 MHz, from JN55VF first "IW" prefix beacon "ON THE AIR" activated from Italy

CB station AP from Lieksa Finland

927.1250 MHz Santiago Peak, CA USA

This page details (in brief) the component changes to modify a Cybernet series 27MHz CB transceiver to 50MHz.

FT-240 toroids measurements. The data was measured using well-calibrated HP instrumentation. All plots have been adjusted to a frequency range of 1-100 MHz on the horizontal axis and a resistance/impedance range of 10-1,000 ohms on the vertical axis. This adjustment facilitates comparison among different materials and aids in determining their suitability for use on the HF ham bands.

An FT-817 ceased transmission on the VHF 2m band, despite the other HF, UHF, and 50 MHz bands operating correctly. Suspecting an excess of input signal during FT-8 mode transmission, they conducted measurements with an oscilloscope, revealing a burnt-out PIN diode, identified as D3003, type HSU277, on the PA unit board. Following the replacement of this surface-mounted diode, their FT-817 resumed operation on the 144 MHz band.

This article describes the implementation and testing of a low-power GPS tracker using LoRa technology in the 433MHz amateur band. The system, built with AIThinker RA-02 modules and Arduino controllers, demonstrated successful communication over non-line-of-sight distances up to 5km. Operating with a 125kHz bandwidth and spreading factor of 11, the tracker achieves a data rate of 500 bits/sec. Powered by a LiPo cell with power-saving features, the final compact design operates for approximately 1.5 weeks between charges with 3-minute reporting intervals, consuming just over 1mA in idle mode.