low bandpass filter

G3SEK's Amateur Radio Technical Notebook - A lot of good informations concerning antennas, filters, moonbounce, and circuitry data.

Crossed-Wire HF Antenna - This Crossed-Wire Electrically-Steerable HF Antenna, capable of transmitting signals over the entire 1.8 to 30MHz HF range, and capable of receiving signals at much lower frequencies is basically a crossed centre-fed wire system, consisting of four thin wires brought to a central mast by G3YNH

160/80m Coaxial Receiving Loop Antennas  ^pop - Receiving loop antenna for top band. This antenna allow to reduce noise on both bands. The stand alone 80m loop is approximately four feet in diameter. And made of light weight material. Which makes it ideal for portable use or you can mount it above a pre-existing vhf antenna, and due to it's small size it is quite rotatable.

Low Noise Antenna Connection - Reducing noise to your antenna can gain your aerial performance, learn how.

Ferrite antenna for LF - A ferrite antenna for Low Freqencies

Whiskey Alpha DX group - "Formed in 1996 in the USA, the ""Whiskey Alpha"" group has members in a few different country's and is growing every day. We provide all members with a ""personalized"" QSL card design. Membership has no annual dues, and is for life."

Microwave Email list - Message list about 903 Mhz. and above bands. Use various VHF reflectors for the 432 and lower bands. Most traffic will be about 2304 and above.

QRP-L Mailing List - Low Power Amateur Radio Discussion

alt.radio.pirate - Low power AM/FM/TV pirate broadcasting.

Workman Electronics - Amateur radio accessories, power supplies, tvi filters, speakers, microphones, swr meters, preamplifiers, switches, cable and connectors,

Dunestar Systems - Manufacturer of single band and multiband transceiver bandpass filters for HF. High pass filters, two radoi headphones mix and switch, 6 meter portable antenna, antenna remote switching and steering.

Davis RF - provide electronic and electrical wire, cable, RF connectors, DSP audio filters, rope, non-conductive guy cables for aerial or tower support; plus sundry aerial related parts

Times Microwave Systems - Manufacture LMR Flexible low loss coax cable, connectors, and cable assemblies for Wireless Communications applications.

Timeware tech. - Amateur Radio Products, Noise Reduction Filters, Data Controllers, deviation meter, Software, DSP-RTTY

Antenna Rotator System  ^{updated  pop} - The ARS will allow to control any antenna rotator (Azimuth & Elevation) from a computer. Even if you are only interested on HF arrays, the ARS will allow it. Supported from most programs as CT for DOS, tracking programs.

NHRC Repeater Controllers - NHRC Repeater Controllers is your provider of low-cost, high-value repeater controllers.

RMS international - RMS International, italian distributor of Alcava batteries and power supply, since 1975 manufacture power amplifiers, watt meters, antenna tuners, TVI filters and other accessories for hams and cb radio

AEA - AEA Technology Inc. is a pioneer and leading manufacturer of RF and cable test equipment for the wireless, Telco, CATV, NMR & MRI, RFID, telemetry, aviation, commercial, military, and two-way radio industries. Produces SWR Meters, Pre Amplifiers, filters, power meters and antenna testing products

Longwave Home Page - The World of Radio Below 500 kHz by the Longwave Club of America

Novel filter for sat working - Elimiate QRM when working with satellite antennas

Super-Duper for Listeners - SDL is a dedicated contest logger for SWLs. It's good for all the major international contests and for dozens of others worldwide. SDL is fully working and unrestricted, and is distributed as freeware. It links to Icom, Kenwood and Yaesu radios to follow band and mode changes.

HamServ - Another way of having your own bbs, using AGW Packet engine. HamServ is a TCP/IP Server program that runs under 32 bit windows and offers support for AX25, HTTP, NNTP, POP3, SMTP, and TELNET. Ideally it should be run under the AGW Packet engine, with the add on TCP/IP driver, it then allows for simultaneous connects via the internet and via packet radio, but it can of course be used stand alone, in which case people will be able to connect to it via the Internet.

Charly 4.0 - WRAASE Slow-Scan-Television (SSTV) commercial windows software, need an external hardware, SC-4 to work.

40MHz Frequency Counter Module - Design for a very low cost 6-digit frequency counter module using of the shelf components

K1TTT Technical Reference Priority listing - Technical reference about Accessories, Amplifiers, Antennas, Cable and Connectors, Filters, Geography, Grounding, Gunk, Matching Networks, Projects, Propagation Info Radios, RFI/EMI, Rotors, Station Setup, Towers.