Tag: radio
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Arduino: 1-Watt 2m Transmitter with RF Signal Generator
Since I do a lot of RF projects, I wanted to see if I could make a 2m power amplifier using a minimal set of components. I have a number of BS170 MOSFET transistors that I’ve used for dozens of applications over the years from guitar pedal pre-amps to digital control circuits. I started this…
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Portable 40m Direct-conversion Transceiver Design
Having finished my master’s degree over a year ago now, I’ve started to see my thesis show up on various academic web sites. I decided I should probably link it on this site in the event that anyone is interested in building and/or designing their own QRP mono-band radio. Additionally, I’ve been doing some more…
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7MHz Transmitter with AVR Soft-keyer
In my last post, I went over the design of a Colpitts crystal oscillator design that put out a moderately clean 7 MHz signal. In order to match the output impedance to 50 Ω, an NPN feedback pair (at least that’s what I’m calling it) was designed. While meeting the specs for driving an ADE-1…
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Testing a 40m Wire Dipole on Mt. Hood
Here’s a quick video showing how I deployed a DIY 40m dipole antenna on Mt. Hood a while back. Though not the most interesting video, I think it shows the results pretty well. I used an AirSpy HF+ supplied by KK7B for a project I’m working on. A Panasonic Toughbook CF-30 helped stave off the…
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mobile APRS setup…
here’s a picture of my mobile APRS setup in the Jeep. it’s been a fun project from time to time. eventually, i plan on constructing a 2m vertical antenna to throw on the roof for better satellite reception while being mobile. i’m currently using a high-gain Comet mag-mount which is an excellent antenna. i was…
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Signals… from space?
none other than. yesterday, i attempted to record some very weak signals for the amateur satellite, ECHO AO-51, with my trusty Yaesu VX-3R. most of my attempts had been unsuccessful until i bought an additional Nagoya N-771 antenna to accompany the tiny 2m/70cm dual band radio. however, i have intercepted the signals from the low-earth…