two tone oscillator

Quad antenna for 10 and 15 Meters - Building guide for a two element quad antenna planned for 28 and 21 Megahertz

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

2 Meter 10 Element Quagi Antenna - This antenna was designed by N6JSX Kuby for Transmitter hiding. Fitting the requirements of directionality, high gain, and portability. This antenna was derived from the ARRL Handbook information on Quagi's and Yagi's; in the absence of two meter Quagi information, UHF Quagi dimensions were scaled into 146 MHz use.

2 meter quagi - A two meter band quagi antenna plan by ku4ay

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

Two portable antennas for 6-meter - VE7CA reprint an interesting article taken from arrl antenna compendium. Two elegant practical and portable 6-meter gain antennas, a two-element quad and a tree-element Yagi antenna for 50 Mhz-6 meter band

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

HB9AFO: antenne Quagi - Two quagi antenna plans for 432 and 144 Mhz, includes dimensions for a 1200 Mhz antenna. In french

The L‐Network Impedance Matcher - N6LYU Greg article on L-Network

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

A two element yagi bean - Simple gain antennas for the beginner, a 2 element yagi antenna

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.

International Crystal Manufacturing Company - International crystal manufacturing provides quartz crystals, oscillators, precision crystals, filters, tcxos / vctcxos, qcm crystals, and other frequency control products. read details about our crystals and frequency control products and services.

MARC: Motorcycling Amateur Radio Club - MARC is dedicated to providing safe and reliable two-way radio communications for selected charity events in their respective regions

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

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

IP-Sound  ^pop - IP-Sound is a Free application for audio exchange client to client over a TCP/IPv4 network (Lan/Internet). The main purpose for the existence of IP-Sound is to provide low quality audio 8-16kHz, with low latency for use together with remote control software for "ham" radio amateur equipment. IP-Sound is developed by SM5VXC.

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.

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.

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

RFI From Computer Networks - Is your router shutting you down ?

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.

9cm transverter - Designed for portable operation, it runs on 12v, and has an OCXO-based local oscillator.