Simple Home-Built Radio Projects
I am a Ham (Amateur) Radio operator, callsign KE3IJ. As such, showing a good, progressive image of Amateur Radio, being "cool", and all that, dictates that I should be flushed with all the latest digital, solid-state equipment in my radio "shack". Pfeh.
Coil-loaded 40/80 Meter Inverted V Dipole Antenna
Coil-loaded 40/80 Meter Inverted V Dipole Antenna This 40 and 80 meter inverted V antenna is made with loading coils. It is a full size antenna on 40 meters and a shortened 80 meter antenna. The antenna is resonate on both bands and does not require an antenna tuner. It's a great HF antenna for the ham radio operator with a smaller backyard!
Adventures with an 80 Meter Loop Antenna, Part 1
Some years ago while I was dating the woman who would become my wife, I thought about setting up a station at her home in Nevada City, California, that I could use when I visited her. Talking with friends on the morning 75 meter net, one recommended that I install a full-wave 80 meter loop. Given her large lot and the pine trees in her back yard that could be used as supports, I thought, "Why not?" I have a huge reel of phosphor-bronze antenna wire -- this is the same wire used to make portable wire antennas manufactured by such companies as TCI. From it I cut a 280 foot length (very roughly 280 feet), added about 50 feet of 300 ohm ladder-line (which was all that I had), and put it up in the back yard with pine trees supporting the four corners in a very crude diamond shape. The ladder-line was routed under the eaves along the back of the house to where a length of RG-142 B/U 50 ohm coax protruded through a hole in the wall.
WSPRlite & End Fed Antenna Testing – Surprise DX on WSPR!
Testing out an LNR 10-20-40 MKII end fed antenna matchbox with a 30 meter wire on the WSPRlite Antenna Performance Analysis System (WSPR beacon). Received some surprise DX today on 30 meters – though Ionosonde charts showed horrible conditions for the day, lesson learned, surprise DX can happen at any time! Baofeng BF-530I P BAOFENG BF-530I The transceiver is a micro-miniature multiband FM transceiver with extensive receive frequency coverage,providing local-... Read more
Trunked Radio: A Guide – AndrewNohawk
TLDR; You can listen to all of the San Francisco CERS (Public Safety) Trunked system at , this guide will show you how you can do the same for it or another trunked system! One of the more common things to do with an RTLSDR (or any SDR for that matter) is to listen to what’s being transmitted. Naturally this often extends to networks of people with radios (sometimes called portables?)
The Alternative Multi-band Solution – Cobra UltraLite Antennas
Covers More Bands than a G5RV (Shorty).Goes up Fast, Easy on Trees.All Stainless HardwareBlack Marine ABS Insulator BlocksHandles a Full kW on All Bands.Tough–Pull-tested for Ice and Snow Loads.Professionally Engineered and Built.Center or End Supported.Fully Assembled with 81-Feet of Ladder Line (40-Feet with UltraLite Kid).NEW UltraLite Kid: 40-6m, Lightweight and Small, Great for Small Lots, Camping, Backpacking.USA-built by Granite State Antenna of Northwood, NH by people who answer the phone. Frequently Asked Questions Where did the Cobra come from? The original Cobra was a homebrew design introduced by Ray Cook, W4JOH, in 73 magazine.
eHam.net
5.37 dBi (2m) and 7.39 dBi (70cm) at 14 ft The Origins In 2012, as I re-entered Amateur Radio, I dug out my old Yaesu FT-5100 that covered 2m/70cm bands for FM. Then, at the Rochester Hamfest (at RIT in 2013 I think), I ran across an old Radio Shack scanner antenna (Model 20-176, thanks to W3OAB for identifying it after I bought it). The seller claimed it covered 2m and 70cm and he wanted $5 for it.
Signal Direction Finding with an RTL-SDR, Raspberry Pi and REDHAWK
Something we missed posting about from last year was this presentation on “RasHAWK”, a direction finding system (pdf) built out of a Raspberry Pi, an RTL-SDR and four antennas on a 4 way switch running software created with REDHAWK. REDHAWK is a visual DSP development platform that can be considered similar to GNU Radio or some parts of MATLAB. The authors write:
3D Printing Your Own Antennas - Antenna Test Lab Co
It Works, and You Can Do It! What RF engineer has not thought about 3D printing an antenna? It’s a natural combination of RF curiosity and and basic 3D printing capabilities. You have probably even seen social media photos and posts about this achievement.
