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40mm diameter grey PVC pipe with a length of 9.5cm

A 40 ft vertical dipole antenna that can cover HF Bands from 80 to 10 meters winding a dipole in a 12m HD telescoping fiberglass pole

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

Homebrew a vertical antenna for 40 and 80 meters band based on popular HF2V model by DL7JV

One of the Portland ,Oregon metro area's oldest club, all are welcome, if you are in the area, our club repeater is on 146.840 mhz

An homemade portable vertical antenna with a trap near the mid point of the main element. The trap is made with 42mm diameter PVC pipe with 9 turns of wire on it

The RigPix database entry provides a comprehensive technical overview of the Icom IC-746 amateur HF/VHF transceiver, detailing its operational parameters and physical characteristics. It specifies the transmit frequency ranges across 10-160 meters plus WARC bands, 50-54 MHz, and 144-146/148 MHz, alongside receive coverage from 0.03-60 MHz and 108-174 MHz. The resource outlines supported modes including AM, FM, SSB, CW, and RTTY, noting a tuning step resolution down to 1 Hz and a frequency stability of ±5 ppm. Key electrical specifications are presented, such as a 13.8 VDC power supply requirement, current drain figures for RX (1.8-2 A) and TX (Max 20 A), and RF output power ranging from 5-40 W for AM and 5-100 W for FM, SSB (PEP), and CW. The entry details the triple conversion superheterodyne receiver system, listing IF frequencies at 69.01 MHz, 9.01 MHz, and 455 KHz, along with sensitivity ratings for various modes and bands. Transmitter section specifics include modulation systems and spurious emission levels. Additional features like a built-in auto ATU, electronic keyer, simple spectrum scope, DSP, and CI-V computer control are noted. The page also lists related documents, modifications, and an extensive array of optional accessories, including various filters, microphones, and external tuners, providing a complete profile of the IC-746.

The idea of using a low mount dipole, enhanced with reflector wires directly beneath the dipole, on the ground, appears to be a very good approach to creating an NVI specific antenna for local HF operation.

A vertical antenna for 40 and 80 meters band with no need of antenna tuner, based on a telescopic fiberglass mast of 48 feet by N8NSN

Experiments with phased wire vertical antennas on 40 meters at VA7ST

This resource details the computer-optimized design of the _ZS6BKW_ multiband dipole, an evolution of the classic _G5RV_ antenna. It begins by referencing the original 1958 RSGB Bulletin article by Louis Varney G5RV, explaining the operational principles of the G5RV's flat-top and open-wire feedline on 20m and 40m, noting its impedance transformation characteristics for valve amplifiers of that era. The article then transitions to the rationale for optimizing the design for contemporary solid-state transceivers requiring a 50 Ohm match. The core of the project involves using computer modeling to determine optimal lengths for the flat-top and matching section, aiming for a VSWR of less than 2:1 on multiple HF bands. It discusses the process of calculating feedpoint impedance based on antenna length and frequency, referencing professional literature from Professor R.W.P. King at Harvard University. The analysis also considers the characteristic impedance (Z(O)) of the open-wire line, identifying a broad peak of adequate values between 275 and 400 Ohms. Specific design parameters for the improved ZS6BKW are presented, including a shorter flat-top and a longer matching section compared to the original G5RV, with a velocity factor of 0.85 for the 300 Ohm tape. The article confirms acceptable matches on 7, 14, 18, 24, and 28 MHz bands when erected horizontally at 13m, and also discusses performance in an inverted-V configuration, noting frequency shifts. The author, Brian Austin ZS6BKW, emphasizes the antenna's suitability for modern 50 Ohm coaxial cable without a balun.

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

Solution to your OEM needs and can meet your design or vended antenna requirements for antennas from 400MHz to 10 GHz.

A vertical half-moxon for the 7 Mhz by F6IRF

Build yourself a postage stamp 40 meter wire dipole antenna that fits in a space a little over 20 wide and works reasonably well at low heights

Ham Radio 20 / 40 meter short Coax Trap dipole antenna designed with the coax trap design calculator program

A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

A multiband antenna that can work from 80 to 10 meters in this illustrated docuemnt by G8ODE

A simple antenna that can be erected very fast, only need one center support, and do not take up much storage room. Works from 40 to 10 meters band

The W1TAG LF Receiving Loop is a specialized antenna project for LF reception, designed to mitigate local noise and enhance weak signal pickup on the lower frequencies. This square loop, measuring 6 feet per side, utilizes 14 turns of #12 THHN wire wound on a PVC frame, offering a robust mechanical structure. The design incorporates a series-tuned circuit with a coupling transformer, allowing for tuning from over 400 kHz down to _45 kHz_ using a switched capacitor bank. Construction details include the use of 1.5-inch PVC pipe for the frame, with specific measurements for spreaders and drilled holes for wire threading. The two 7-turn sections of wire are connected at the center, providing an option for a center tap. The loop rotates on a 1-inch steel pipe, enabling directional nulling of noise sources. The tuning unit, housed in a box clamped to the PVC, employs a 1:2 step-up transformer wound on an _FT-82-77 core_ and uses relays to switch capacitance values from 50 pF to 6400 pF, providing precise frequency adjustment. The current setup connects to the shack via 100 feet of RG-58, feeding into a W1VD-designed preamp, with plans for a balanced, shielded twisted pair cable upgrade.

A 40 80 dipole antenna design by WA6ESC PDF File

Survey of galactic synchrotron radiation at 408 MHz in the south of England using a 10 metre dish and a Dicke radiometer

3 Band vertical Marconi-antenna for the bands 40, 80, 160 meters with a ground net of wires as radials.

Gary Breed, K9AY experience with beverages on 40 meters

A shortened dipole for 40 meters band by Martin E. Meserve

A homebrew fishing-rod vertical using a very nice design from EB5EKT. This antenna works 20, 30, and 40M bands by selecting the tap points using alligator clips

This article explores a theoretical model for the losses of an 80m / 40m trapped inverted V dipole antenna system using a bootstrap coax trap, but does not examine the pattern of the antenna.

An inverted V antenna for 40-80 with loading coils. This antenna is a full size on 40 and a shortened 80 by KG0ZZ.

30/17/12 and 20/15/10-Meter Tribanders and a 40 meters inverted V wire yagi antenna

Pictures of a 2 meter, 220, 440 copper J-Pole antennas

This project outlines the construction of a 3-element reversible quad antenna specifically designed for the 40-meter band. The materials required include pushup towers, pressure-treated posts, insulated wire, and various electrical components such as relays and a balun. The construction process is straightforward, beginning with the installation of the posts in a straight line, followed by the assembly of the antenna elements and their elevation to the desired height. The antenna's design allows for directional signal reception, making it ideal for operators looking to enhance their communication capabilities on the 40-meter band. The project includes detailed instructions on tuning the antenna for optimal performance, ensuring that operators can achieve the lowest SWR possible. Additionally, the design can be adapted for other bands by extrapolating dimensions, providing versatility for amateur radio enthusiasts. Overall, this reversible quad antenna project is suitable for both beginners and experienced operators, offering a practical solution for improving signal strength and directionality in 40-meter communications.

A Mini Moxon antenna for 40 meters band project in a well done PDF document

The MFJ-940 VERSA TUNER II is a useful little antenna tuner for the HF-bands. However it suffers from a minor design error, which can be easily rectified.

A multiband 20/40/75/160 trap dipole antenna plan by KG0WX

YF1AR 80 to 40 meter vertical antenna project

A W3DZZ trapped dipole for 80 40 and 20 meters band by ZL1BJQ

A wire yagi antenna model, easy to build, made using inverted vee elements and requiring just one support by ve3vn

A three-frequency multi-band dipole that can be extended easily to additional bands. This article includes a multiband fan-dipole antenna for 80-40-20-10 meter band.

A well documented article on a small magnetic loop antenna for the 40 meters band

This is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It is a dipole fed off center with a 4:1 current balun at the offset feedpoint. The antenna shown covers 80, 40, 20 and 10 meters with 15 meters and WARC bands

The ZS6BKW wire antenna, a variant of the G5RV, utilizes a specific 13m (42.6 ft) length of 450-ohm window line as its matching section, feeding a 28.5m (93.5 ft) flat-top element. This design aims for lower SWR on 40m, 20m, 17m, 12m, and 10m compared to a standard G5RV, often achieving SWR values below 1.5:1 on these bands without an antenna tuner. The feedpoint impedance transformation provided by the window line allows for direct connection to 50-ohm coax on multiple bands. F4FHH's experience involved constructing the ZS6BKW and evaluating its performance against an _OCF dipole_ (Off-Center Fed) on various HF frequencies. The article includes observations on SWR readings and operational effectiveness, highlighting the ZS6BKW's suitability for multi-band operation. The antenna's overall length, including the flat-top and window line, is approximately **41.5 meters** (136 feet), making it a significant wire antenna for fixed station use. Comparative analysis with the OCF dipole provided practical insights into the ZS6BKW's advantages and limitations, particularly concerning bandwidth and tuner requirements.

An home made trapped dipole antenna for 40 and 60 meters band by 2E0HTS

Regenerative receiver for 5 amateur bands : 80 40 20 17 15m by F5LVG

Vintage and reproduction electronic parts specialist - Antique radio dials and knobs, 1940-1970 era phonograph cartridges, needles, idler wheels.

A shortened 7 MHz Dipole antenna as described by Ken GM4JMU in Sprat 74.

A page about a Magnetic loop antenna project for the 40 meters band, includes nice pictures and history of construction

Based on DL6UW Yagi antenna's design-formula The forward gain is 13.6 dBi (about 11.5 dBd) and it's pretty small, about 1,5 m in length

Local and DX contacts from tight spaces, it works from 40 to 17 meters

Demonstrates the essential steps for winding **toroidal cores**, a fundamental skill for amateur radio operators engaged in homebrewing and kit building. It addresses the critical aspects of selecting the correct core material and wire gauge, emphasizing the importance of precise turn counting and consistent winding tension to ensure optimal circuit performance. The resource details methods for preparing the wire, including techniques for safely removing enamel insulation from leads using flame, sandpaper, or a solder pot, and provides guidance on tinning the exposed wire. Explains the process of mounting the wound toroid onto a printed circuit board, highlighting the need for careful lead placement and secure soldering to prevent shorts and ensure mechanical stability. It also offers a practical formula for calculating the required wire length based on the desired number of turns and the specific **toroid** size, referencing common core types like T-50 and FT-240. The guide stresses the importance of verifying the inductance of the wound component, often using an inductance meter, to confirm it matches design specifications. Provides practical tips for handling multi-filar windings and managing short lead lengths, which can be particularly challenging. It underscores the necessity of meticulous attention to detail throughout the winding and installation process to achieve reliable and efficient RF circuits.

A telescopic pole that you adjust to suit the band you're working on , tested on 40 20 and 15 meters band by M0PZT