Cheap radio frequency plasma generator - This page details how a RF plasma source of approximately 1 kW can be constructed from house-hold materials. Possible uses include plasma cleaner, plasma etch, remote activation species generation and no use at all (my personal favorite). __ Designed by Greg Miller
Class B series Modulator - Schematic only__ Amfone.net
CMOS
Logic Inverter Amplifier characteristics - This chart shows some of the measured characteristics of three different unbuffered CMOS
logic gates, used as voltage amplifiers. . . Circuit by Dave Johnson P.E.-February, 2002
Collection of Crystal Radios - Collection of Crystal Radio Circuits __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Compact 25 GHz Fractional N, PLL Synthesizer - 12002500 MHz RF Source subassembly. The design consists of: Fractional N PLL, modular VCO, Dividers, RF harmonic filters, AGC leveling loop, and output amplifiers. The 4 layer PCB was designed with Coplanar waveguide over groundplane and Stripline techniques for very low sensitivity to manufacturing tolerances and very low assembly costs. __ Designed by Steve Hageman
Complete 30 GHz Fractional N, PLL Synthesizer / source - 7503000 MHz RF source subassembly. The design consists of: Fractional N PLL, discrete VCO, Dividers, RF harmonic filters, precision AGC leveling loop, and output amplifiers. The 6 layer PCB was designed with Coplanar waveguide over groundplane and Stripline techniques for very low sensitivity to manufacturing tolerances and very low assembly costs. __ Designed by Steve Hageman
Constructing Scotty Sprowls' 1 GHz RF Spectrum Analyzer - This is a series of notes and videos on constructing the 1 GHz RF spectrum analyzer project by Scotty Sprowls. __ Amateur Radio circuits from Green Bay Professional Packet Radio
Convert 2m VHF FM PMR transceiver Motorola Radius M110 into an AM ateur radio - Turn a professional 2m VHF FM PMR transceiver Motorola Radius M110 into an amateur radio __ Designed by Aleksander Stare
Converter to Hear AM ateurs on your FM Radio - If you're the sort who'd like to have an HF receiver in every room, but can't afford it, this idea is for you. It will also appeal to the beginner wishing to build the simplest possible direct conversion receiver. Using a readily-available FM wireless microphone kit, it is possible to broadcast the audio output of a homebrew direct conversion receiver around your property and beyond. __ Designed by Peter Parker VK3YE
Converter to yune six metres on your two metre receiver - If you're the sort who'd like to have an HF receiver in every room, but can't afford it, this idea is for you. It will also appeal to the beginner wishing to build the simplest possible direct conversion receiver. Using a readily-available FM wireless microphone kit, it is possible to broadcast the audio output of a homebrew direct conversion receiver around your property and beyond. __ Designed by Peter Parker VK3YE
COR Carrier Delay timer / Hang Timer - Did you ever want a simple controller to key a transmitter from a receiver's cos? Well here is a simple circuit that does just that. The input impedance is fairly high, about 1 Meg, and will interface to most any receiver. VR 1 is a sensitivity control that is adjusted to trigger the circuit with just about any available positive going signal. A setable hang time is adjusted with VR 2. __ Designed by Kevin Custer W3KKC
Cordless Phone Backup - Normally the base of a cordless phone has an adaptor and the handset has Ni-Cd cells for its operation. The base unit becomes inoperative in case of power failure. Under such__ Electronics Projects for You
Crystal heater / temperature stablization (TXCO) - OK, here is the circuit I usedSee image below. The original National Semiconductor circuit had a 30 K resistor in series with a 400 µF cap., both in parallel with the 100 K resistor on the input of the 1st LM324 section. I found that combo to actually destabilize the operation of the controller for this particular application, so I removed them & changed the 2 µF cap in series with the 10 megohm resistor to 5 µF. __ Designed by Bob Dengler NO6B
Crystal Radio - RF Receivers & Receiver Circuits Crystal Radio __ Designed by Aaron Cake
Crystal Radio - I have been listening stories from dad that he made a radio when he was little younger than me. It was hard to digest that his radio worked without power! I thought, its nothing more than those interesting old stories that we have been told at bed time!! __ Designed by Nina Gajjar
Crystal Radio - The crystal radio gets its name from the galena crystal (lead sulfide) used to rectify the signals. A "cat's whisker" wire contact was moved about the surface of the crystal until a diode junction was formed. The 1N34A germanium diode. __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Crystal Radio - This is a generic circuit, the first true radio receiver in history. Description: Crystal radio requires no power supply to operate because it uses energy from the signals it receives. Performance is like one should expect poor. Nevertheless, __ tomzi.geo page
Crystal Radio RF Amplifier - One of the best places to add a transistor to a simple crystal radio is at the front end in the form of an RF amplifier. The circuit below is a simple but effective amplifier which will give surprising performance improvement. This amplifier __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Crystal Radio Set Version 2 - This uses a more standard ceramic / crystal earpiece and LT44 transformer that you can buy easily. Look out though, this is a draft version. __ Designed by Henry
Crystal Radio--make your own - Circuit Only __ Designed by Charles Wenzel
Crystal switcher using diodes - Schematic only, no circuit description __ Designed by Guy Roels ON6MU
CW Beacon Keyer - This circuit stores a morse code message as bits in an EPROM chip, the message controls a relay that keys a CW (morse code) transmitter. An Arduino processor can also be used in place of this circuit, that eliminates the need to build the circuit and program an EPROM. __ Designed by G. Forrest Cook |