two tone

Portable Magnetic Loop Antenna Version 2 - A simple multi-band magnetic loop antenna designed for 20, 30 and 40 metres. For its size, the performance of the antenna always astounds me, although it is never going to replace a Yagi

The 2-Element-HB9CV-Beam  ^updated - The HB9CV-Beam is a 2-Element-Yagi with two driven elements and was introduced by Rudolf Baumgartner, HB9CV in the 1950ies. The Beam is a coax-feeded version of the ZL-Special Construction by DK7ZB for 2m, 6m and 10m

50MHz Power Splitters - Splitting an antenna between two receivers or in use as the phasing harness in stacked antennas where there is a need to equally split the power from the transmitter between two antennas

Antenna Transmission Line Power Splitters - Several ways of splitting power to feed two like (50 ohm terminal impedance) antennas.

Remote Control Antenna Switch - The Remote Control Antenna Switch consists of two circuit boards. The control unit and the remotely controlled switch

Antenna Cable Loss and SWR - Calculate Cable Loss from SWR and reverse. Text file with only two simply formulas

A two band halo for VHF Mobile - 50 and 144 Mhz with a single mobile antenna system

Mirrored J-Pole - The mirror-image J-Pole is very easy to construct and requires only two T-Fittings plus a length of copper pipe.

Cross-Yagi antennas - For two purposes a Cross-Yagi can be useful Satellite work or if you need both vertical and horizontal polarization for terrestrial contacts

Citizens Band Radio . Org - UK CB Radio forum A great place for information of DX n the UK. Information on antennas radios and Expiditions in the UK.

Bavarian Packet Radio Group - This site provides information about the BayCom packet radio hard- and software for radio amateurs. It also contains general information on the German packet radio network.

D-Region Absorption Prediction - This map represent the current position of the sun and how a solar flare influence an HF fade. Estimated recovery time is also represented. Includes son java and javascript animations of last two hour conditions

Two Way Radio Battery - TwoWayBattery.com is your source for high quality two way radio replacement batteries, chargers, eliminators and accessories. Batteries for major brands Alinco Icom Kenwood Motorola Uniden Yaesu Standard and more

BatteryZone - Batteries and accessories for two-way radios including Icom Kenwood Yaesu Alinco Midland Motorola Uniden and more

CQ Shop Ham Radio Store Hong Kong Priority listing - Hong Kong's only full-service amateur radio store. Full line of Amateur Radio and Two-way equipment and accessories from companies such as Yaesu, Icom, Kenwood, Motorola, MFJ, Alinco, Diamond, AOR and many, many more. Knowledgeable staff with many years of experience in the radio business TAX-FREE shopping (no sales, VAT, GAT or other taxes) HF, VHF, UHF transceivers, receivers, walkie-talkies, antennas, antenna tuners, coax and connectors

PI-EL - The Windows program for designing and analyzing PI and PI-L networks by Tonne Software

Beacons - The W6AMT Beacons is a Windows program which automates the collection of radio propagation data. HF data is collected by monitoring the worldwide network of NCDXF / IARU HF beacons.

Elsie - Filter Design - Filter design software. Elsie is an uncommon commercial-grade lumped-element ("L-C") electrical filter design and network analysis program, directed toward the engineer or technician involved in that line of work.

WINRAD by I2PHD  ^{updated  pop} - Winrad is a free software program designed to implement a Software Defined Radio (SDR), meant to run under Windows XP, Windows 2000, or Windows 98SE. In a nutshell, it accepts a chunk of up to 96 kHz coming from a complex mixer in form of two signals, I and Q, fed to the PC sound card.

Base-Station RF Power-Amplifier Biasing - Power amplifiers used in base stations require biasing for proper RF performance. This article explains the two classes of biasing that are prevalent in the RF industry, analyzes their characteristics, and shows implementations with existing ICs.

13cm RF Amplifier - This amplifier uses two 60w Spectrian amplifier boards with the usual input and output hybrid coupler and combiner.

IK8MKK Home-Made equipment - Two 50 Mhz amplifiers and antenna switch

Duplexer for VHF and UHF - Duplexer to use two transceivers and one antenna VHF UHF in spanish

A diode-switched band-pass filter - High speed silicn diodes work well as RF switches. This article describes how to use diodes for selecting two or more filters ARRL QST article by W1FB

An Inexpensive PL Tone Encoder - If your local repeater has got you singing the PL tone blues, then read on. For less than $10, an inexpensive PL tone generator can be constructed that will bring new life into that old non-PL rig.