cable

cable

Pages: [prev] ... 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

• Beverage Transformers for HF Receiving Antennas - This FAQ covers building and buying transformers for loop-on-ground and Beverage antennas. Building one uses ferrite cores and thin wire. Buying is an option, with the DX Engineering BFS-1 being recommended. These transformers isolate the antenna from the cable to prevent unwanted signal pickup.
  [ Hits: 21 | Votes: 0 | Rating: 0 ]
• The Reversible BOGs - The author struggled with receiving antennas on his property. After a standard Beverage on Ground (BOG) antenna failed, he built a Reverse Beverage on Ground (RBOG) using telephone cable. He details construction and testing, finding the RBOG outperformed other antennas in noise level, signal strength, and reception pattern. Software modeling helped optimize the antenna length. Unfortunately, the project ended when telephone cable from the second RBOG was stolen.
  [ Hits: 23 | Votes: 0 | Rating: 0 ]
• Reversible RG6 Beverage Antenna - The author describes building a reversible Beverage antenna for low-band receive applications. He details the construction process, challenges faced, and initial performance testing. The antenna uses coaxial cable and transformers for switching direction. Overall, the author is pleased with the results and plans to build additional reversible Beverages.
  [ Hits: 21 | Votes: 0 | Rating: 0 ]

• Build a Simple VHF Dipole Antenna for 2 Meters: A Beginner's Guide - This article serves as a beginner-friendly guide to constructing a simple VHF dipole antenna for 2 meters, perfect for novices in the hobby. With an emphasis on affordability and simplicity, it explains the basics without overwhelming technical details. Recommendations for coaxial cable and mounting methods are provided, offering practical solutions for effective communication. By following these instructions, novices can build a functional antenna without breaking the bank.
  [ Hits: 114 | Votes: 1 | Rating: 7 ]

• Multi-Band End-Fed Antenna Design for Limited Space - This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.
  [ Hits: 76 | Votes: 0 | Rating: 0 ]

• RF Choke with Bifilar Windings - This article presents an RF Choke featuring an 11-bifilar turn winding of #14 house wire on a Fair-rite FT240-31 toroid. The choke is enclosed in a 3D-printed case from Thingiverse, though this may pose thermal concerns at higher power levels. With SWR concerns up to 30MHz, the author plans to employ two series chokes at the rig input for improved performance. This choke offers versatility for portable use, with potential mismatch resolution using an antenna tuner. Further testing is anticipated upon the arrival of new cables.
  [ Hits: 86 | Votes: 0 | Rating: 0 ]

• Aluminium Push Up Mast - A DIY aluminium push up mast project. The final mast includes 7 aluminium tubes with 6 cable clamps
  [ Hits: 358 | Votes: 3 | Rating: 6.67 ]

• Ribbit digital text messaging mode for HF/VHF/UHF - Ribbit is a novel digital text messaging mode for VHF/UHF communications for recreational and emergency use which radically increases the density of information transmitted by spectrum used. It leverages the computing power of the modern smartphone to increase the capabilities of any Handy Talkie without requiring any additional hardware or cable. A Ribbit message is fixed in duration at 1250 milliseconds. It is sent over audio modulation with a 2kHz bandwidth centered on 1.5kHz. It is preceded by 400ms of white noise to open analog squelch circuits.
  [ Hits: 133 | Votes: 1 | Rating: 10 ]

• Kenwood TH-F6A Cable - Build a cable to connect your PC to the Kenwood TH-F6A radio
  [ Hits: 40 | Votes: 0 | Rating: 0 ]

• Building an Enhanced APRS IGate with Debian 12 and Raspberry Pi - The guide outlines necessary components, including a 2m FM analog radio, USB audio adapter, and Raspberry Pi. Building a cable to connect these elements is assumed, as is knowledge of Raspberry Pi OS installation.
  [ Hits: 58 | Votes: 0 | Rating: 0 ]

• Beverage Remote Switch  ^new - The author describes building a remote switch box to control the direction of two reversible Beverage antennas. The switch uses a buried cable and relays to select the desired antenna direction from the shack. The design is simple and uses common components.
  [ Hits: 38 | Votes: 0 | Rating: 0 ]

• USB-C charging for Handheld Radio Transceivers - The article highlights the common absence of modern USB-C ports on handheld ham radios and the limited use of USB for power. The author, [jephthai], shares a solution involving a USB-C cable with power negotiation capabilities, allowing the radio to be powered by USB. By splicing Anderson power pole connectors onto the cable, the radio can now be conveniently powered by a USB battery bank, providing a practical alternative to traditional 12 V batteries for off-grid operations.
  [ Hits: 143 | Votes: 1 | Rating: 10 ]

• Understanding Impacts of 75-ohm Devices in 50-ohm Systems - This article explores the implications of using 75-ohm devices, common in TV setups, within 50-ohm systems. While mismatched cables and connectors may lead to minimal consequences in receive-only setups, potential losses and reduced isolation in splitters and taps are examined. The article concludes that, for general applications, inexpensive TV-type components can offer reasonable performance with some trade-offs
  [ Hits: 150 | Votes: 2 | Rating: 9.5 ]

• Yaesu FT-891 Go-Box for POTA - This article documents the author's latest go-box build for outdoor ham radio operations using a Yaesu FT-891 transceiver. The go-box is constructed from a plastic "50-cal ammo case" and contains various components, including the transceiver, LDG Z11 Pro autotuner, DIY Yaesu FH-2 remote control keypad, and an external battery. The author details the design considerations, the mounting of components inside the box, and addresses issues related to ventilation and cable management. The go-box is geared for CW operations and POTA activations, with further modifications planned for a microphone and DATA jack. This project allows for rugged, environmentally protected outdoor radio operations while maintaining portability.
  [ Hits: 198 | Votes: 0 | Rating: 0 ]

• A Universal Programming Cable for Radios - The programming cable is intended to be used with a computer RS-232 port for programming radios and other devices. The main goal of this cable schematics is inverting signal levels.
  [ Hits: 90 | Votes: 0 | Rating: 0 ]

• Prevention and Suppression of RF Interference to Audio Systems - In this study, the author builds upon Muncy's research, demonstrating that radio-frequency current on cable shields affects audio systems through the "pin 1 problem" and shield-current-induced noise (SCIN). An enhanced equivalent circuit for ferrite chokes is proposed, addressing dimensional resonance and inductor self-resonance. Field tests confirm that chokes reduce interference across 500 kHz to 1,000 MHz. Guidelines for diagnosing and mitigating EMI from various sources are provided for product development and field installations.
  [ Hits: 47 | Votes: 0 | Rating: 0 ]

• Reducing RFI from PoE Devices - Hams can be annoyed by noise from PoE cameras and access points. These devices and their long cables act like antennas, picking up and spreading unwanted radio signals. By wrapping ferrites around the cable will reduce this noise. It won't silence it completely, but it can make a big difference.
  [ Hits: 29 | Votes: 1 | Rating: 6 ]

• Baofeng UV5R TRRS Adapter - A tiny board, which allows a smartphone or similiar device to connect to the Baofeng UV5R radio via a TRRS audio connector. It allows for connecting the radio to a software TNC app such as APRSDroid or PocketPacket. Solder on the components, solder on the cables, then provide some stress relief, (I use solid-core wire and heat shrink tubing), and you can use your UV5R with your smartphone for APRS on the cheap.
  [ Hits: 91 | Votes: 0 | Rating: 0 ]

Pages: [prev] ... 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19