Micro Spy with FETs - Circuit and notes only, no circuit description given. __ Designed by Tony van Roon VA3AVR Micro Spy with TTL - This circuit is old (70's) but since the 74LS13 is from the regular 74xx series and easy to obtain, I decided to keep the circuit in place until components are no longer available. Not much to tell here. Performance is based on the 74LS13, a 'Dual 4-input Positive-Nand Schmitt Trigger'. This circuit was experimental and so has no real purpose other than tinkering. __ Designed by Tony van Roon VA3AVR
Micro Spy with USW - Circuit and notes only, no circuit description given. __ Designed by Tony van Roon VA3AVR
Micropower AM Band radio station - The picture to the left is a high quality radio transmitter for the A. M. broadcast band. The transmitter legally operates with "micro-power" and will not set any distance records but, unlike simpler designs, the frequency stays put and the fidelity is excellent. Although the schematic looks somewhat complex, the circuitry is easy to build and adjust for experimenters with a little "tweaking" experience. A simple output meter confirms proper signal level and checks antenna tuning while "on the air". Add an audio mixer, tape recorder, and perhaps a CD player and have a near-professional micro-power station. __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Mini RF frequency synthesizer using an MC12095 & MC12080 or MB 501 - This Project generates an rf carrier based on a pll • with an MC12095 and MC12080 or MB 501 • locked on a 10.000 MHz reference
__ Designed by Alexander C. Frank, aka Ajarn Changpuak
Mini Tracker - This beeping bug can be attached to anything from a glider to a pot-plant and you can track it with an FM radio. Why track a pot-plant? Read on to find out__ Contact Collin Mitchell
Mixer & Preamplifier for String Instruments - Most of the small musical bands have up to four string instruments like guitars and violins. The signal from the transducers of these instruments should be buffered and sometimes amplified before...__ Electronics Projects for You
Mix-It: an Easy-To Build 4-Channel Mixer - Anyone can build this high performance four-channel audio mixer...__ SiliconChip
MK484 AM Receiver - A complete AM radio set based on the MK484 IC (formerly ZN414). it uses a PNP transistor and can drive a 150R loudspeaker __ Designed by Chad Castagana
Mobile Bug Detector - This handy, pocket-size mobile transmission detector (Mobile Bug) can sense the presence of an activated mobile phone from a distance of one and a-half metres. So it can be used to...__ Electronics Projects for You
Mobile Phone Battery Charger - Mobile phone chargers available in the market are quite expensive. The circuit presented here comes as a low-cost alternative to charge mobile telephones/battery packs with a rating of 7.2 volts, such...__ Electronics Projects for You
Mobile Phone Multipower Unit - Most of the mobile phone complaints are related to the power supply. This is mainly because of improper charging and use of non-recommended chargers and low-quality batteries. Depending upon the make...__ Electronics Projects for You
Mobile Sniffer - This circuit can detect the use of a GSM mobile in mobile-phone-restricted areas such as examination halls and other ‘do not disturb’ areas. it can detect the activity of the phone...__ Electronics Projects for You
Modern Homodyne (Simple Circuit but great!) - Last winter I have constructed a simple receiver, called the “Modern Homodyne”. Full information is provided in two articles by G.W.Short which were published in The Radio Constructor (March 1972, p.492-495, and April 1972, p.552-557) __ Designed by Aren van Waarde
Modern Converter - Here is my design for a modern receiving converter for pre-war FM sets__
Modernized Drake FS-4 Synthesizer for the Drake R-4 and SPR-4 series receivers - The Hagtronics - Drake Crystal Eliminator (Featured in QST) __ Designed by Steve Hagerman
Modulated light receiver circuit - The circuit uses a very inexpensive C-MOS IC that is connected to a small photodiode. Using a unique inductive feedback network, the circuit provides high sensitivity under high ambient light conditions. it is a great circuit when you want to extend the range of an optical remote control transmitter. . . Circuit by David A. Johnson P.E.-June, 2000
Modulation Monitor - Very simple and useful circuit used to monitor on air transmission of your low power amplitude modulated transmitter. __
Montreal Doppler 3 DF (direction finder) unit - The Montreal Doppler iii is an update of its predecessor - the Montreal Doppler ii. it is recommended that you read about them on their respective official pages. Please note that this was NOT an official page of VE2EMM - please read the disclaimer at the bottom of this page. __ Designed by KA7OEI
More crystal sets - Response to December's column was so favourable that we return to crystal sets and allied topics this month. Keep reading to find out how to improve your AM broadcast reception, make your crystal set deliver hi-fi audio and set a fashion trend with the all-new 'wearable wireless' pedestrian mobile crystal setamateur radio construction projects. __ Designed by Peter Parker
Morse Adaptor for your VHF/UHF FM rig - Everyone knows that the best way to practice Morse is to use it on the air. But how do you send Morse if you don’t have a multimode HF or VHF transceiver?Well, you could hold a microphone up to a code practice oscillator, and hold the PTT down while pressing the key, but it’s very clumsy, and the transmitted tone is likely to be harsh. Clearly something better is needed. __ Designed by Peter Parker
MPF102 FM Receiver - An FM regenerative receiver using a single FET and one audio amplifier IC . __ Designed by Andy Collison
MPF102 Receiver - Schematic only. __ Designed by Patrick
MRX 40 Mini Receiver - After exploring very low power (QRPp) communication by building a 40 meter Micronaut CW transmitter, 1 I took on the challenge of constructing a tiny 40 meter companion receiver. Not only did I think the receiver would complement the Micronaut, I thought it might also have potential as a kit project for my hometown group, the CQRP (Columbus, Ohio, QRP) Club. The final push to action came from the discovery that there were 93 licensed amateurs in my neighborhood ZiP code __ Designed by Steve Bornstein, K8IDN
Musical Ladybug - Our son Henk is fond of small animals - bees, bugs, waterbugs, frogs, hedgehogs, newts, fishes and toads. They are caught in the gardens and ponds around our house and neatly stored in vessels, jars and containers for careful study. After a few days of confinement they are returned to their natural environment (and in unhappy cases, caught again within a few days). So when we decided to give Henk a radio for his sixth birthday, it could not be a dull grey portable from Radio Shack. For this special occasion we designed the one and only musical ladybug. __ Designed by Aren van Waarde
MW Enhanced Crystal Receiver using 741 IC - Ham Radio - V-U) HF AMPLiFiER - Schematic __ Designed by Guy Roels ON6MU
MW/SW Radio receiver - Schematic only, no circuit description __ Designed by Guy Roels ON6MU |