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FlexWire Automatic Transverter Selector - Google Foto. AD0MZ/All-Band-Adjustable-Dipole: Motorized 10-80 Meter Adjustable Dipole. Small Transmitting Loop Project. Matt Roberts — matt-at-kk5jy-dot-net Updated: 2021-01-19 Introduction Of the many different antenna projects I have built for HF, the most interesting and rewarding project was the small transmitting loop.

Small Transmitting Loop Project

After consulting many of the available Internet sources, and by combining ideas, I was able to assemble an antenna that performed well, even under poor band conditions. The experience was so much fun that I built several different ones, all described below. Thinking About Loops. The Loop on Ground Antenna - the "LoG" Published: 2016-04-10 Updated: 2018-12-30 Antennas made from conductors installed flush with the ground are not a new idea.

The Loop on Ground Antenna - the "LoG"

The Beverage antenna is an example of an antenna that is typically installed within a few feet of the ground, but as a special case, it can also be installed directly on the surface — an arrangement called a "Beverage on Ground" or "BoG. " The Beverage antenna is not the only antenna type that can be installed close to the ground. Other more conventional antennas can be installed on the ground in order to obtain specific performance characteristics. RF Current Meter. Why a Hand Held RF Current Meter There are two things that I wanted to do which would be made easy with a current meter...

RF Current Meter

Both are related to the unusual nature of the antenna here at AC0C. 1. Checking common mode surface current on coax and control cables up in the attic antennas. With the high cost of ferrites, placing them with the aid of a current meter is very helpful in that you can compare the before (no ferrite) and after (with ferrites attached) - and know that you have addressed the current problem on a given bit of line. Otherwise, it seemed to me, that ferrite placement was more of a guess than a science. Clamp-on RF Current Meter. A clamp-on RF ammeter is not only useful for antenna experimenters but also as an aid to achieving good EMC in an amateur station.

Clamp-on RF Current Meter

If some of the RF current from a transmitter flows into mains wiring, this can increase the chance of breakthrough problems in nearby TV, video or audio equipment etc. A clamp-on RF ammeter allows this current to be measured, so that steps can be taken to minimize it. For RFI investigations, you can also clip this meter on to coaxial cables, rotator cables and other wiring in your shack, to find out where the RF currents are flowing, and how big they are. You can also use this tool for measuring currents in wires and radials. Instead of splitting a ferrite ring in half, RSGB EMC Committee member David Lauder, G0SNO, has been experimenting with various types of ferrite core which are already split, as shown in Fig 1 (below). Ham Radio Site - {Different Kinds of Chokes} (B) Improved Coaxial Choke This is a very simple choke to build.

Ham Radio Site - {Different Kinds of Chokes}

The material costs are low, and it is very rugged. You won't burn this one up. Our HAM Station - Notes on the construction and operation of a multi-op Amateur Radio Station. G3TXQ. I became interested in radio in the late 1950s when my parents bought me an Ivalek crystal set as a Christmas present, and later on an ex-army receiver - the Wireless Set R208 - which was advertised at the time as the "Sputnik Special" because it covered the low VHF frequencies used by the first Russian satellites.


I passed my Amateur radio exam and morse test in 1965 and got the callsign G3TXQ. QRPpJournal of the Northern California QRP Club Volume 1, 1993 Volume 2, 1994 Volume 3, 1995 Volume 4, 1996 Volume 5, 1997 Volume 6, 1998 Volume 7, 1999 Volume 8, 2000 Volume 9, 2001 Volume 10, 2002 Volume 11, 2003 Last Minute Additions Note that these are very large PDF files.

Power Supply Safety Covers for Astron RS-35A by lorenmcconnell - Thingiverse. This is a set of safety covers for an Astron RS-35A power supply.

Power Supply Safety Covers for Astron RS-35A by lorenmcconnell - Thingiverse

I use one of these supplies to power my ham radio equipment. It is reliable, quiet, and produces clean electrical output. The NDB List Datamodes Section. Astron Power Supply Index Page. Note: there is an Astron Wireless Technologies company that makes some very nice antennas.

Astron Power Supply Index Page

It is a totally separate operation with no connections to the Astron Corporation that makes power supplies. Astron makes both linear and switching power supplies, and some other products. You should read this Astron Introductory Information article before any of the other articles here in the Astron section It has some very useful information on the Astron linear and switching power supplies, with background, history, model-specific information, both repair and modification suggestions, photos, and more. The Pyramid Gold Series linear power supplies are very similar in design and capacity to the Astron supplies. Both are based on the popular LM723 voltage regulator integrated circuit.

A Photo Tour of a Bird Wattmeter Element. I bought two Bird elements on a popular auction site: 5 watt, 400-1000 MHz (5E) and 100 watt, 400-1000 MHz (100E).

A Photo Tour of a Bird Wattmeter Element

Both were listed as new old stock (NOS). I put them into my meter about a week after they arrived, connected the meter to a radio and dummy load, keyed the radio, and the needle moved for each one. The other day I picked up a used 80 watt UHF base station and wanted to measure the output power. Project Information Index. Build your own RF sampler / Iso-Tee for the Bird model 43 Thruline Wattmeter. General Description: This construction article will help you take a dummy slug (more correctly called the dust / safety plug) and with some simple drill press machining, build a very useful RF sampler / Iso-tee for feeding a service monitor, spectrum analyzer, etc., and for a lot less than what Bird wants; (over $100 at the time of this writing!)

If you don't have a dust plug, one can be obtained from Bird directly or a stocking dealer. Concept: The Bird Model # 43 Thruline Wattmeter is a very common test tool among Repeater Builders worldwide. This article will show you how I took a simple dummy slug and turned it into a very useful tool for testing for desense, monitoring waveforms, and feeding other equipment.

I've tried to make this article as detailed but concise as possible to benefit readers. This modification process will not disturb the original intent of the dummy slug; keeping out the dust and shunting the meter movement in travel. Written and HTML'ized by Kevin K. Tips Tricks Info. Ham radio and SWL. Build an APRS IGate – WCARES. Why build an IGate? SV3ORA website. Disclaimer You are free to copy and use everything on this non-profit amateur website. Note that for copyrighted material, you may need to ask for the authors permission first. All material on this website is provided as is without any guarantee. Many of the material is my own thoughts and do not necessarily represent the truth. It is provided for you to read in order to understand the basic principles of operation. If you find your material is listed somewhere in this page and you want to remove it or get credit for it, please let me know and I will remove it immediately or add relevant notes.

. * I am paying lots each year for maintaining this website and you get that for free, please gain knowledge from what you find here and be reasonable about copyright stuff anyway. Website intentionally built using web 1.0 technology. A stand for the Yaesu FT-817(ND) - KR1ST. The Yaesu FT-817(ND) is a marvelous little radio with lots of features. One feature, however, is notably absent from this radio. A stand that will lift the front of the radio, so you can actually read the display and reach the controls, is not included. There are several solutions on the market that are well worth looking at, but they will set you back by $20 to $60. If you like to homebrew things and are interested in building your own stand that is sturdy, compact and is virtually free, then read on. BUILD AN AIR WOUND 1:1 CHOKE BALUN FOR HF - THE UGLY BALUN! Another Ugly Choke Balun by G4APL Paul, G4APL, has brought together some excellent examples on how to construct and build Choke Balun in the pictures above and the information below to share with us: Paul decided to build two or three of them, depending on what material could be found in the shed.

The idea was to add a balun to the HF beam, a Mosley Mustang Mark3 3 element 10,15, 20 metre trapped yagi. FLAT MAGNETIC LOOP ANTENNA , loop magnetico morbido i6ibe pratola peligna. FLAT MAGNETIC LOOP portable ANTENNA pdf. Improved Dutch helix/helical for WiFi. High Gain Yagi Wi-Fi Antenna. The leading resource for "Roel Roscam Abbing" on the web! Dave Richards AA7EE. The BIG List of RTL-SDR Supported Software. There are now dozens of software defined radio packages that support the ultra cheap RTL-SDR. On this page we will attempt to list, categorize and provide a brief overview of each software program.

We categorize the programs into general purpose software, single purpose software, research software and software compatible with audio piping. If you know of a program that is missing please leave a comment in the comments section at the bottom of the page. General Purpose RTL-SDR Software We define general purpose SDR software as programs that allow the RTL-SDR to work like a normal wideband radio receiver. BM800 Microphone Mods -       Welcome to Dual Band SDR Receiver -       Welcome to Remote Balanced Aerial Matching Unit -       Welcome to Astron Power Supply Meter Modification. w4zt astron power supply meter modification. Adding Digital Metering to Astron 14V Linear Power Supplies. all new! 1.8M EME Dish Project. My CB Installation (in detail)

Stunning Ultra-HD View; Sun Timelapse 2015 (NASA/SDO) VU2ESE's radio experiments: Specan - A reboot of the W7ZOI/K7TAU spectrum analyzer. An easy to build spectrum analyzer for the homebrewers. The KA7OEI FT-817 page. Update your FT-817, FT-857, or FT-897 with the new 60 meter channel. In the US starting in 2003, amateurs have had a secondary allocation of five specific channels in the 60 meter band. f1ehn. Digital Audio Filter Modules - SOTABEAMS. Vk3ye. The Chart of the Electromagnetic Spectrum - Quad Questions.