Comparison of Beverage antenna
- A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands
W8JI Technical pages
- Amplifier, vacuum tube, receiving beverage loop vertical and transmitting antenna system technical information radiation resistance, EH antenna, noise,receivers, and information on keyclicks.
160/80m Coaxial Receiving Loop Antennaspop
- 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.
VLF-LF And the Loop Aerial
- The article discusses the theory of loop aerials for receiving and how they reduce the level of local noise. A Loop Aerial is described suitable for use on the LF and VLF bands together with a circuit of an interface loop tuner and preamplifier. The discussion extends to the problems of amplifier noise and the advantages of tuning the loop.
[ Hits: 2853 | Votes: 5 | Rating: 5.40 ]
Antenna Noise and Signal Cancelling at LF
- The fact that the phasing between a wanted signal and an unwanted signal can be different on different antennas is put to advantage. With this condition, the unwanted signal can be cancelled out by controlling amplitude and phase. The heart of the system is some form of phase control circuitry.
KØBG's ham radio mobile operator web site
- This site is dedicated to mobile amateur radio operators, old and new alike. Whether you are into HF, or VHF operation, I trust the information presented will increase your enjoyment of our great hobby.
With safety as a byword, there are articles on amplifiers, antennas, bonding, impedance matching, installing hardware, mobile equipment, noise and RFI abatement, wiring, and much more. I do my best to keep these articles up to date, and easy to follow.
- Discount CB & Accessory Distributor. Top Brands such as Cobra, Uniden, Midland, Galaxy, Solarcon, Bandit, Pyramid, Wilson, Superstar, Palomar, Nortstar, President, Dosy, Paradynamics, K40, Nemarc, Road Noise, Astatic, Turner, Telex. Best Prices and exceptional service. 21 Years serving the Communication Trade.
Scanrec Scanner Recorder
- Scanner Recorder (Scanrec) is a free audio recorder that is primarily designed to record speech. It has a VOX control that allows the user to save disk space when no sound is present in the signal. Since FM communications has such an effective squelch, the recorder works best with FM. HF ham bands and World Band radio have such a poor signal to noise ratio that the VOX gate on Scanrec might not be very easy to set.
WD6CNF DSP Filter
- Audio Digital Filter, two bandpass filters, three notch filters, two noise filters
graphical setting of filter center frequency and bandwidth Drag vertical lines on top of signal,
Microphone input, speaker output
Mono, 5 kHz bandwidth
- A freeware program to dig out weak signals buried in noise, functionally similar to the excellent FFTDSP of AF9Y, but with the added bonus of real time audio filtering of the incoming signals. Just point and click with the mouse, and the selected signal will stand out from the QRM and noise.
144 MHz preamplifier with BF981
- Design of a preamplifier for 144 MHz with 1 dB NF and 23 dB gain using BF981. This amplifier is using a low cost silicon MOSFET (BF981 from Philips) to give more than 20 dB gain with around 1 dB noise figure on 2 meter.
23 cm GaAs FET preamplifier
- On 23cm the best way to obtain a good RX-sensitivity is to use a GaAs-FET in the front-end, since these devices show very low noise figures.
[ Hits: 3421 | Votes: 5 | Rating: 5.20 ]
Receive only processing equipment
- One of our most popular products, receiving preamplifiers are used for achieving top signal band performance in competition operating, low noise longwave reception, repeater applications into the UHF region, or lab use
Antenna Noise and Signal Cancelling at LF
- By using the signals from two antennas, controlling their relative amplitudes and controlling the phase of one of them, unwanted signal or unwanted noise can be phased out. Circuitry is described which uses the signal from a wire antenna to provide selective cancelling against the signal output from an LF loop antenna.
[ Hits: 6796 | Votes: 3 | Rating: 6.00 ]
QRM and noise reductionPriority listing
- You will find on these pages my experiences and results on antennas and local/non-local QRM/noise reduction. Using a broadband vertical active magnetic loop and a home made / designed broadband amplifier. Two vertical magnetic Alford loops are used in an array.
Analog and Digital Signal Processing and a dual phase coherent Software Defined Radio (SDR) are used. By PA0SIM