filter 80m

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

Vertical antenna for 40 and 80m - Homebrew a vertical antenna for 40 and 80 meters band based on popular HF2V model by DL7JV

Center-Loaded Off-Center-Fed Dipole - 6 band - Multiband Center-Loaded Off-Center-Fed Dipole (CL-OCFD) antenna that work on 80m 40m 30m 20m 15m 10m by ON4AA

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.

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

Array Solutions - WX0B - Stacking and phasing HF and 6m arrays antenna switches and contesting devices. Custom low band antenna arrays, bandpass filters,commercial/Mil STd filters,microwave components, commercial broadcast filters.

WIMO - All kinds of antennas, RF connectors, radio transceivers and accessories like power supplies, morse keys, lowpass filters and so on.

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

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

INRAD International Radio - Supplier of custom designed, high performance quartz crystal filters for communications receivers and transceivers, for Yaesu Icom Kenwood and Collins radios

Heros Technology Ltd - HF Radio Preselectors,BCB filters,Low Pass filters,Band Pass filter

HD Communications - Rf Connectors,RF Amplifiers,RF Filters,HF cable and accesories. Tower hardware valves and tubes

Kiwa - Filters and performance upgrades for many receivers

Bencher Inc. - Paddles, Keys, Filters, Antennas

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

Vectronics - Antennas, Filters, accessories, wattmeters, tuners and amplifiers.

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

Spectran - Program designed to do spectral analysis and real-time audio filtering on reception of audio signals for EME, VLF, SETI applications. Offer support for MTHELL, QRSS, DFCW, NDB, WSJT by I2PHD

CwGet  ^{updated  pop} Priority listing - A program to decode morse code (CW) via sound card to text. It can work as narrow-band sound DSP-filter also. No additional hardware required — you need only receiver and computer with a sound card. Can integrate with AALog logger.

Tunekit - Filter Tuning Kit for Windows is a electronic filter synthesis program and a practical filter tuning aid for actually designing and building a working filter

TVI and BCI Filters - TVI and BCI bandpass and bandstop filters in SMD technique. Schematics and images.

Lowpass filter for 5MHz - The following lowpass filter was built using the tables in the arrl manual, it is a 5 section one and seems to work ok

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.