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A solutiom for the Ameritron AL-811(H) RF power amplifier, burnt panel meter lights. A common failure with the Ameritron AL-811 and similar amplifiers is that the panel meter lights burn out prematurely. These bulbs are usually integrated into the actual panel meter. The solution for this is to provide the meter backlighting with LEDs. -
A 21 MHz Four Square Beam Antenna This popular antenna for the lower bands, can also work well on 15 meters, QST Article -
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Improper grounding or earthing system can cause several unwanted RF interferences (RFI) to television sets, broadcast receivers, hi-fi sets and telephone sets. In this Article the author explain how to setup a proper radio shack grounding using coaxial cable and ceramic disc capacitor -
Adding extra directivity to the Moxon Rectangle for 6m, 4, and 2m -
Service manual in PDF Format for the Yaesu FT-7800 transceiver -
An end fed 20 meter half wave antenna -
VHF UHF diplexer by G8MNY -
A moxon rectangle for 50 Mhz band -
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Part 2 You're now much closer to saying goodbye to your unwanted signal problems! -
A Useful Horizontally Polarised Omni-directional Antenna with Gain for 144 MHz -
A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space -
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A PDF presentation about Amateur Radio and Linux by By: Dave Mamanakis. A beginners guide to Linux for radio amateurs, this presentation cover basic concepts of the open source operative system, from the basic installation to the setup of ham radio programs. -
An home made vertical dipole antenna made with simple material. The antenna has a total length of aproximately 16 feet. In this article appeared on June QST 2019, the author explain how he reached the optimal confirugation changing and adjusting the lower part of the antenna, trimming and spacing correctly the copper wire. PDF File to downloas -
A scanned PDF of this interesting book on HF Dipole antennas published by Stanford Research Institute -
Roger, G3XBM, shares his extensive experience in **QRP** (low-power) amateur radio operation, detailing various aspects of transmitting with minimal power. The resource provides insights into VLF (Very Low Frequency) reception techniques and the construction of simple **crystal radio sets**, reflecting a foundational approach to radio experimentation. It includes links to external resources covering QRP clubs, online receivers, manufacturers, and technical references, offering a curated collection for enthusiasts. His page serves as a hub for those interested in the challenges and rewards of QRP, often comparing the efficacy of different low-power setups. The practical application extends to understanding basic radio principles through hands-on projects like crystal sets, which G3XBM has explored. The collected links provide a starting point for further research into specific QRP equipment or operating practices, drawing on G3XBM's long-standing engagement with the QRP community. -
This interface is intended to be used with all the popular digital modes like PSK31, RTTY, Olivia, etc., which modulate a continuous carrier. -
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Schematic of Yaesu FT-857 main board original jumpers based on different radio type -
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Optimizing performances of the end-fed antennas QRP quarterly article -
An excellently presented article on the design and construction of a medium wave DX Antenna -
In this article K3DAV show a very simple way to make an RF choke coil that will remove your RF feedback troubles -
Packet Radio networking home page with lots of informations and tech. resources -
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Optimization tests of the W3EDP multi-band HF wire antenna a popular aerial among QRP enthusiasts because it is light weight and cheap. -
Optimizing the ZS6BKW antenna for full HF band coverage often requires specific modifications beyond its standard configuration. This resource details several enhancements, beginning with a simple series capacitor to improve 80m SWR, a technique W5DXP found effective for permanent installation due to its minimal impact on higher bands. Further improvements include a 10-inch parallel open stub for 10m resonance, shifting the frequency to 28.4 MHz with an SWR of approximately 1.8:1, a practical solution for Technician class operators. The document then explores a switchable matching section, adding or subtracting one foot of ladder line at the 1:1 choke-balun, which significantly impacts higher frequency bands and eliminates the need for a tuner on 17m. W5DXP's _AIM-4170D_ antenna analyzer measurements confirm these effects. More advanced modifications involve a parallel capacitor for further 80m SWR reduction, requiring remote switching for multi-band operation, and relay-switched parallel capacitors at specific points on the 450-ohm matching section to achieve low SWR on 60m, 30m, and 15m. These detailed steps, including _Smith chart_ analyses for the challenging bands, aim to transform the ZS6BKW into a truly all-HF-band antenna, reflecting W5DXP's practical experience in antenna tuning. -
A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor -
There are 2 possible TX extensions on the E version, either full TX (1.705 - 30 MHz) or just open up 5 MHz (cut the R968 jumper and make it into a K version). This mod has been tested on TS 590S and not on TS 590SG -
A multi-band portable vertical antenna can be built with relatively ordinary components obtained from the local hardware store, including replaceable loading coils -
Experiments with spiral dipole antennas. Includes two spiral antenna designs for 20 and 40 meters band by KN9B -
The ZS6BKW multiband antenna, an optimized variant of the classic G5RV, features a 102-foot (31.1 m) horizontal span and a 39.1-foot ladder line matching section. This design, derived by G0GSF (formerly ZS6BKW) in the early 1980s using computer programs and _Smith charts_, aims for improved SWR across multiple HF bands compared to its predecessor. Construction details specify Wireman 554 ladder line and #14 AWG THHN copper wire for the radiators, with precise instructions for determining the velocity factor (VF) of the ladder line using an antenna analyzer or dip meter, ensuring accurate physical length for the matching section. The radiator length is electrically 1.35 wavelengths for the 20-meter band, requiring careful trimming during tuning. Field measurements with an _AIM-4170C_ analyzer by KI4PMI and NC4FB demonstrated good SWR curves and bandwidth on 6, 10, 12, 17, 20, and 40 meters. The antenna was deemed unusable on 15 and 30 meters due to very high SWR, but an LDG AT-100PRO autotuner successfully brought 6 and 80 meters into tune. Contacts were made on 80, 40, 20, and 17 meters, including a **17-meter** contact to Spain. EZNEC models for 80-6 meters are provided, along with an AutoEZ model by AC6LA, which predicted good SWR for 80-10 meters. W5DXP's modifications for an all-band HF ZS6BKW are also referenced. -
A Variable Base-Loading-Coil for use under a HF Mobile Whip -
Intended for portable long-term usage and also good for Field Day Events article by By Steve KB1DIG & Kim KB1GTR -
This article is designed to be an introduction to the terms and basic mechanics of propagation methods that are to be found on the HF and VHF bands. -
The skeleton slot antenna design was developed in the UK for TV use soon after WW2. This document describe and adapted version for the 2 meter band -
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Yaesu FT-2000 Panadapter, using the Softrock 9 Lite, SDR receiver kit -
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CWQSO allows you to practice sending and receiving morse code in a real QSO. You can send CW via the mouse buttons or an attached paddle, the CW you send is displayed on CWQSO -
A magnetic loop antenna working from 30 to 15 meters with 100W -
A two meter Quad antenna project with detailed instructions on how to adjust the Quad gamma match -
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An Experimental, High-efficiency, Graphic-Tunable Magnetic Loop antenna and loop controller in a 52 pages PDF presentation with drawings and pictures -
This is an Android application used to remotely control several HAM radio Web SDR or any CAT enabled transceiver -
This is an experimental CW transceiver for 80m, although the same idea will work on all HF bands -
The GM3VLB Poor Man's Antenna Analyser