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Query: alan 5
Links: 148 | Categories: 3
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Personal pages on CB radio in the SE of UK and my involvment with the Tango Echo DX group -
Alan Applegate (K0BG) article on mobile oprtations -
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Home of the Richmond Amateur Radio Club, Richmond, BC, Canada -
Presents a detailed compilation of **6-meter** voice repeaters operating within the 53-54 MHz segment across Australia (VK) and New Zealand (ZL), providing essential data for local and visiting radio amateurs. Each entry specifies the repeater's output and input frequencies, its assigned callsign (where applicable), the primary service area, current operational status (e.g., operational, under construction, scrapped), and a **Maidenhead grid locator**. The resource also includes the date the repeater was last heard or updated, offering insights into its recent activity. This listing is meticulously maintained by VK2KFJ, who updates entries based on personal observations and confirmed reports from other operators. It serves as a practical reference for hams seeking to utilize the 6-meter band for local communication via repeaters, particularly for those engaged in mobile or portable operations within the specified regions. The data helps operators configure their transceivers correctly for accessing these vital communication hubs. Beyond the repeater details, the page also notes common 6-meter FM voice simplex frequencies, such as the 52.525 MHz international call frequency, and lists historical packet simplex frequencies, though their current operational status is uncertain. This comprehensive approach ensures that operators have a broad overview of 6-meter activity in VK and ZL. -
An illustrated and printable introduction to PSK 31 by by Alan J. Gibbs, VK6PG -
A small Z-Match tuner, BLT, Balanced Line Tuner is a simple Z-Match tuner that works from 10-40 meters -
Wiki Site dedicated to radio scanning info in New Zealand -
Here you will find information on how antennas behave when stacked G/T is an important figure-of-merit for the antenna's overall receive performance, because it balances forward gain (G) against received thermal noise (T). -
Stop common-mode current when transmitting with an end-fed antenna. Unbalanced antennas are very prone to currents on the outside of the coax. -
New Zealand Amateur Radio 70, 32 & 23 cm (UHF) Repeaters -
An unconventional antenna family, the VHF/UHF Zigzag Dipole Antennas. Design, theory and practical construction, transformation and balancing with a half wave balun. -
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Balanced feed with coaxial line by John F. Clemens W9ERN -
The T-Match with its balanced feed point is one method of feeding a Balanced Dipole. -
New Zealand Association of Radio Transmitters -
Constructing a high-power 70cm solid-state amplifier presents unique challenges, particularly when aiming for 500 watts output using modern LDMOS devices. This resource details the author's experience building a 70cm amplifier based on a _Freescale MRFE6VP5600H_ transistor, initially from an RFHAM kit. It meticulously outlines the necessary modifications to achieve advertised performance, including optimizing input and output matching, correcting bias circuitry, and ensuring proper output balun connections for stability. The author shares specific adjustments, such as trimming the prototyping board for better transistor fit, drilling additional mounting holes for improved heat sinking, and replacing original matching capacitors with a single _20pf MIN02 metal mica_ for superior output. A critical fix involved jumpering gate decoupling pads to balance the push-pull transistor halves, which increased output to 580W and improved IMD. The resource also highlights a crucial correction to the output balun connection, initially reversed in the _Dubus_ article schematic, which resolved intermittent stability issues. Test results are provided, showing input power, output power, and drain current at 50V, demonstrating the amplifier's performance after modifications. This practical account offers valuable insights for hams undertaking similar high-power UHF amplifier projects, especially those working with LDMOS devices and kit-based constructions. -
Radio New Zealand International is a Shortwave Broadcaster. Our broadcasts are beamed to the island nations of the Pacific but can also be heard in other parts of the world. -
Details the construction of an **HF converter** designed by M1GEO, George Smart, specifically to extend the frequency range of the FunCube Dongle Pro (FCD) for amateur radio reception. The FCD natively covers 64 to 1,700 MHz, but this project enables reception from 0 Hz to 64 MHz by up-converting signals to the FCD's operational range. It employs a **double-balanced mixer** with a 100 MHz local oscillator (LO) to translate incoming HF signals; for instance, a 1 MHz signal appears at 101 MHz within the FCD's passband. The design incorporates a 7th-order Chebyshev low-pass filter with a 62 MHz cutoff frequency at the input to mitigate image frequencies, ensuring cleaner spectral presentation. George provides the schematic, PCB masks, and Gerber files for replication, noting that Far Circuits also offers PCBs. The resource includes test results for the low-pass filter and measurements of LO leakage, identifying -36.8 dBm at 100 MHz as a potential sensitivity concern. M1GEO discusses potential improvements, such as adjusting the mixer's LO drive, adding a balance pot, or incorporating a post-mixer high-pass filter to reduce LO breakthrough. Audio recordings from 40m and 17m demonstrate the converter's performance with WRplus SDR software. -
This article describe the principles of baluns when referred to devices used to balance unbalanced systems, like a coax cable and a dipole antenna -
Wiring a Balanced Microphone to the TS-590S Unbalanced Microphone Input -
Design a parallel circular wire balanced transmission line with this online calculator. This calculator is a tool for designing balanced transmission lines with a specific desired characteristic impedance Zc and made of parallel circular conductors of a given diameter d. -
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Trio Datacom, Dolectek and Yaesu Vertex Standard cb and ham radio dealer in new zealand -
This R.F. current meter was developed to assist in measuring line currents in balance feed lines as used in the All Band HF Antenna. -
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Presents a concise guide for Amateur Radio operators participating in Jamboree-on-the-Air (JOTA), an annual event connecting approximately 500,000 Scouts and Guides worldwide via ham radio. The resource details how to initiate a voice contact, including the use of "CQ Jamboree JOTA" and proper signal reporting with the RST system. It also outlines the typical exchange information, such as name, QTH, Scout rank, and age, encouraging participants to practice their responses. Authored by Bill Wetherill, N2WG, the brochure provides a practical phonetics chart and a comprehensive Morse code dictionary, including punctuation and prosigns like AR and SK. It clarifies rules for third-party operation under the direct supervision of a licensed operator, noting restrictions on international contacts without specific government agreements. Additionally, the guide lists recommended World Scout Frequencies for SSB and CW across 80, 40, 20, 17, 15, 12, and 10 meters, emphasizing courteous operating procedures. It includes a section on common Q-signals like QRM, QRN, and QSL, alongside the Amateur's Code, which stresses considerate, loyal, progressive, friendly, balanced, and patriotic conduct. -
RF Solutions is your authorised distributor of superior amateur radio products in Australia, New Zealand, and the Asia Pacific region -
There is a common perception that placing a balun on the input of a tuner causes the balun to work better. The thought is the balun operates with a matched impedance and that reduces balun losses. It also is thought that moving the balun improves balance. -
Moxon is a rectangle shaped directional antenna, originally designed by Les Moxon G6XN. There are couple of advantages of using this antenna. It is small in size, Easy to mast, Balanced to 50 Ohms, Near 1:1 SWR, Excellent Front to Back (F/B) ratio, Large bandwidth -
Strictly Ham has a large retail presence in Australia and welcomes enquiries from New Zealand, the Pacific and Asia. Strictly Ham offers a comprehensive range of high quality Amateur, CB and Marine products at very competitive prices. -
Hand made RF sweeper made to adjust the pass band of crystal filter -
Assorted links to almost anything. -
A non-profit organisation devoted to the preservation of early radio equipment and associated historical information. -
DX-Expedition 1996 8Q7BU and personal info -
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An home made doblet antenna made with two Slinkys that are aproximately five meters in length connected with a twin-feed connected to a balanced ATU -
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1500 watts PEP SSB is the power handling capability of the MFJ-989C HF Antenna Tuner, a popular choice among amateur radio operators. Users have shared a wide range of experiences, with some praising its durability and performance over decades of use, while others criticize its build quality and accuracy. The tuner features a built-in dummy load, SWR-wattmeter, and a balun for balanced line feeders, making it versatile for various antenna setups. However, discrepancies in RF power readings and SWR measurements have been noted, with some users finding the dual scale meter to be off by about 20% compared to a Bird wattmeter. Long-term users report that the MFJ-989C performs well with proper antenna setups, but caution against tuning at high power without initial adjustments at lower power levels. Some have experienced issues such as arcing when exceeding 400 watts, while others have had no problems even at higher power levels. The roller inductor and capacitors are functional, though some users have had to perform maintenance like tightening screws or cleaning components to ensure reliable operation. Despite mixed reviews, the MFJ-989C remains in production, suggesting continued demand. It's a tuner that requires careful handling and possibly some DIY fixes to achieve optimal performance. -
Listen to the New Zealand 70cm National System. -
This EXCEL Program Worksheet calculates the common-mode impedance of a 1:1 Guanella (current) balun which is placed at the feed point of a balanced antenna system fed via coax. -
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If you ever asked if you need an Unun or a Balun this article is for you. The right question should be do I need a feed line choke or an impedance transformer whose output is configured as balanced or as unbalanced. An impedance transformer can be configured as a voltage transformer or as a current transformer. -
New Zealand, the information has been taken from the New Zealand Call Book, published annually by NZART -
Listen to the New Zealand 70cm National System. -
Haredata Electronics is your one stop shop for Power Supplies, Chargers, Battery Packs & Accessories. Power Supplies Chargers, Battery Packs , Power Supply Accessories , Haredata Electronics Limited, -
Information and download page for the CQ/X GPS-enabled logging program for mobile operation in amateur radio state and regional QSO parties by N05W -
The resource, "Conventional Use of Transmission Line," meticulously details the operational principles of transmission lines, emphasizing the Transverse Electromagnetic (TEM) mode of energy transfer. It clarifies that for a line to function purely as a transmission line, all currents must be confined internally, with external fields ideally zero. The discussion differentiates between balanced and unbalanced lines, asserting that while both require equal and opposite currents within the conductors, the key distinction lies in the voltage relationship of each conductor to the surrounding environment. It highlights that a good antenna pattern does not inherently confirm proper feeder balance, and that common-mode currents can lead to RF in the shack and increased noise levels, even without pattern distortion. The article further explains that a transmission line can become a radiating conductor if energy is applied in a non-TEM mode, leading to common-mode issues. It cites classic texts like Jordan and Balmain's "_Electromagnetic Waves and Radiating Systems_" and Kraus's "_Antennas_" to support its definitions of TEM mode operation. The content also explores non-transmission line applications of parallel or concentric conductors, such as _coaxial dipoles_ and _folded dipoles_, which intentionally operate in non-TEM modes for antenna functionality. The author, _W8JI_, stresses that simply measuring equal currents is insufficient to confirm a balanced feeder; phase and voltage balance to ground are equally critical.
