multi mode

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

W5GI Mystery Antenna  ^pop - W5GI Mystery Antenna is a multi-band wire antenna that performs exceptionally well even though it confounds antenna modeling software. This antenna covers 80 to 6 meters with low feed point impedance and will work with most radios, with or without an antenna tuner. It is approximately 100 feet long, can handle the legal limit, and is easy and inexpensive to build. It�s similar to a G5RV but a much better performer especially on 20 meters.

Slinky and loaded beverages - How slinky loaded beverage antennas works, includes eznec models

Common Mode Choke Theory - A common mode choke may be used to reduce a type of electrical noise known as common mode noise. Electro-magnetic interference (E.M.I.) in the circuit's environment is one source of electrical noise.

G5RV Antenna Homebrew - Homebrew G5RV a simple multiband antenna by 9M2ZAK

J-Pole antennas for 2m-40m - A multiband jpole antenna

Loop Antenna Design - Full-wave loops are very popular antennas. They are especially useful on 80 and 40 meters where they perform well at modest heights

The Fan-tenna - A Safety multi-band mobile antenna by Robert Wilson, AL7KK

5 Band Cubical Quad - EI7BA multiband cubical quad

Picture of a multiband dipole  ^pop - Pictures of a multiband dipole, build with simple PVC T and standard electrical wire

Multiband yagi antenna plan - F6CHT plan for a multiband yagi antenna that covers 6 to 30 meters band in french

LU9DPD Windom dipole - A multiband windom dipole antenna for 80 40 20 10 meters, feeded with a home made 4:1 balun, in spanish.

Multiband vertical antenna - An article with pictures on a 80-10 mt vertical antenna with an Unbalanced-Unbalanced balun in italian

Easy way antenna systems - Written by John M. Haerle, WB5IIR (SK). A must read for anyone considering building a good low cost HF multi-band antenna system.

Coaxial Traps for multiband antennas - A new perspective on the analysis and design of this popular antenna element. By Karl-Otto Müller, DG1MFT

Sound samples of digital transmissions - Sound samples of the transmission modes recorded at 11025 samples per second, mono and the message in all of the samples is the same: "the quick brown fox jumps over the lazy dog 1234567890".

SSB Electronic USA - manufactures and distributes HF, VHF, UHF and SHF equipment covering 10MHz. - 47.0GHz. Our products include: Wireless LAN / WAN Bidirectional Linear Amplifiers, Low Noise Preamplifiers - LNA's, RF Linear Amplifiers, Relays, Transverter Systems, Frequency Translation Systems, Downconverters, Antennas, Parabolic Dishes, Coaxial Cable, Relays, Antenna Switches, Microwave Test equipment, PC controlled Receivers, Microwave Linear Amplifiers including models for Telemetry, Wireless, and CDMA applications.

Opek Tech - Tawainese antenna manufacturer. Multi-Band HF/VHF/UHF Mobile Antennas

microHAM - Supply high quality accessories for your ham shack, including Band Decoders, various types of Antenna Switches, Antenna Stacking devices, special devices designed for the SO2R operator, USB Interfaces, Digital Mode Interfaces, Keyers and many others

Multi-Tech Industries, Inc. - Manufacturing Precision Products Since 1969. Rotary Switches, Strain Reliefs, Ground Fault Units

QSK for the TL-922 and SB-220 mods - Beautifully constructed amplifiers. Unfortunately, are not suited for high speed T-R switching, a necessary attribute for operating AMTOR, QSK-CW, or SSB-VOX modes.

Radio Scanner Guide - A guide to selecting Radio Scanners; divides both new and used radio scanners into 6 categories, based on their specifications and features - e.g. analog trunking scanners, digital trunking scanners, etc; provides specifications on each model

Antenna Model - Commercial software for the analysis of wire antennas. runs under most Microsoft 32-bit Windows operating systems—Windows 98/ME/NT4/2000/XP Analyze most wire antennas in free space, over perfect ground, or over real-world grounds with the conductivity and dielectric constant you specify. You describe the antenna to the program in easy-to-use spreadsheet-style input window

WASP-NET - Complex CAD and Optimization Software for Waveguide, Coax, Combline and Antenna components design and antenna modelling

gMFSK - Linux free multimode HF terminal program. Despite the name, gMFSK can send and receive many digital conversational modes typically used by radio amateurs on HF. Supported modes are: MFSK (MFSK16 and MFSK8) RTTY THROB (1, 2 and 4 throbs/sec) PSK31 (BPSK and QPSK) PSK63 MT63 Feldhell