In the world of ham radio, every contact (QSO) tells a story—of signal propagation, atmospheric conditions, and, sometimes, antenna alignment quirks. While most hams are well-versed in optimizing transmit paths, the reverse path often gets less attention. But here’s the thing: for every successful two-way communication, what gets sent must also come back—and if your antenna isn’t properly oriented for that return trip, you could be missing out on cleaner, stronger signals.

So, let’s break down what reverse path antenna orientation really means for amateur radio operators—and how it can improve your operating experience.

What Is Reverse Path Antenna Orientation?

Think of reverse path antenna orientation as paying attention to how your antenna hears, not just how it transmits.

In a typical QSO, your antenna transmits a signal to a distant station. That station, of course, transmits back to you on the same or a different frequency (depending on mode and band). If your antenna is directional—like a Yagi, quad, or even a rotatable dipole—its physical orientation will affect how well it receives signals from that station’s direction. That’s your reverse path.

In essence:

“Your signal may be getting out fine, but are you listening in the right direction?”

Why Reverse Path Orientation Is Crucial in Ham Radio

Many hams are surprised to find that they can be heard five-nine but are barely pulling in the return signal. If you’re running a directional antenna and not thinking about your receive path, here’s what could be happening:

1. Directional Imbalance

You’re pointed toward your target when transmitting, but not necessarily maximizing reception if conditions favor a different return angle—especially on HF bands where ionospheric skip can cause inbound signals to arrive from an unexpected direction.

2. Polarization Mismatch

On VHF and UHF, especially with horizontal vs. vertical polarization differences, your antenna’s receive sensitivity can be greatly reduced on the return path if it’s not matched properly with the transmitting station’s orientation.

3. Asymmetric Propagation

Especially on bands like 10m or 6m, propagation can vary dramatically minute-to-minute. The reverse path may favor a different skip zone or reflect differently off the ionosphere—requiring small adjustments for best reception.

4. Local Obstructions or Noise

If one side of your antenna’s pattern faces toward a power line, building, or RF noise source, your receive quality can tank even though your transmit signal is fine.

How to Optimize Reverse Path Performance

Here are a few things you can do to make sure your station hears as well as it talks:

• Use a rotator and pay attention to both ends of the QSO. After you get your report, ask the other station where they’re hearing you from—then tweak your orientation as needed.
• Try switching antennas for receive. Many hams use a separate receive antenna (like a loop or beverage antenna) especially on low bands (80m, 160m) where noise or directionality can be a challenge.
• Play with polarity on VHF/UHF. If you’re working simplex or weak-signal work, try rotating your beam 90° to see if the signal comes up.
• Use tools like reverse beacon networks or PSK Reporter. These can give you insight into how well your signal is getting out—and from where others are hearing you.
• Log signal direction for both RX and TX. This helps you track propagation changes and can inform better orientation during contests or nets.

Real-World Example

Imagine you’re working 20 meters and calling a station in South Africa. You’re pointed southeast. They give you a solid signal report, but you’re struggling to copy their reply. By swinging your beam a few degrees east, or even slightly north, you find a sweet spot where their signal peaks—maybe due to a different ionospheric reflection on their end. That small adjustment just improved your receive path and made the QSO solid.

Final Thoughts

In ham radio, we often obsess over our “signal getting out,” but it’s equally important to listen smarter. Reverse path antenna orientation is a subtle but powerful concept that can help you dig weaker stations out of the noise, improve contest scores, and get more enjoyment from the hobby.

So next time the bands are open, don’t just transmit—tune, turn, and truly listen. That elusive DX might already be calling you back… you just need to be pointed in the right direction.

73 and good DX!

Amateur radio, often referred to as “ham radio,” has long been a platform for experimentation, communication, and community building. While traditional voice and Morse code communications still hold a cherished place, the integration of digital platforms has revolutionized the ham radio experience. These platforms leverage modern technology to provide enhanced communication capabilities, allowing amateurs to connect more efficiently and creatively.

What Are Digital Platforms in Amateur Radio?

Digital platforms in amateur radio involve transmitting data using digital modes rather than traditional analog methods. These modes encode information such as text, images, or even files into a digital signal that can be transmitted over radio frequencies. At the receiving end, specialized software decodes the signal back into its original form.

Popular digital platforms include:

• FT8: A highly efficient, low-bandwidth communication mode ideal for weak signal environments.
• PSK31: A real-time keyboard-to-keyboard chat mode known for its simplicity and effectiveness in low-power operations.
• JT65: Designed for weak signal communication, often used in moonbounce (EME) operations.
• APRS (Automatic Packet Reporting System): A digital system used for real-time communication of information like location, weather, and messages.
• DRM (Digital Radio Mondiale): A platform for transmitting high-quality digital audio and data.

C4FM (Continuous Four-Level Frequency Modulation) is a digital communication protocol widely used in amateur radio systems, particularly in the Yaesu System Fusion platform. Developed by Yaesu, C4FM is designed to enhance voice clarity and data transmission reliability in digital radio communication, catering to both amateur and professional radio operators.

Key Features of C4FM

1. High Voice Quality: C4FM is known for its superior voice quality, achieved through advanced error correction and efficient encoding techniques. This makes it ideal for clear communication even in challenging signal conditions.
2. Multiple Modes: C4FM supports various communication modes:
   • Voice FR (Full Rate): Provides high-quality digital voice transmission.
   • Voice + Data: Allows simultaneous transmission of voice and low-rate data (e.g., GPS information or text messages).
   • Data FR (Full Rate): Enables high-speed data transfer, which is particularly useful for sending images or larger data packets.
   • Analog FM Compatibility: Ensures backward compatibility with traditional analog FM systems, allowing seamless integration with older equipment.
3. Automatic Mode Select (AMS): Radios using C4FM often feature AMS, which automatically detects and switches between digital and analog signals. This ensures smooth communication regardless of the mode being used by the transmitting station.
4. Integration with Yaesu System Fusion: C4FM is a cornerstone of the Yaesu System Fusion digital communication system. This platform integrates C4FM with features like WiRES-X (Wide-coverage Internet Repeater Enhancement System), enabling global communication through linked repeaters and nodes.
5. Efficient Spectrum Utilization: C4FM’s design optimizes spectrum use, making it suitable for congested frequency bands. Its robust error correction ensures reliable communication, even in areas with weak signals.

Applications of C4FM

• Amateur Radio: C4FM is popular among ham radio enthusiasts for its flexibility and high-quality performance. It supports both casual communication and emergency operations.
• Public Safety: The protocol’s reliability and clarity make it valuable for first responders and other public safety professionals.
• Data Communication: The ability to transmit GPS data, text messages, and images extends its use beyond voice communication.

Advantages of C4FM

• High-quality audio with minimal distortion.
• Compatibility with analog systems for easier transition to digital.
• Flexible modes for voice and data transmission.
• Robust performance in varying signal conditions.

Challenges

Despite its advantages, C4FM faces competition from other digital radio protocols like DMR (Digital Mobile Radio) and D-STAR. Each protocol has its strengths, and the choice often depends on user preferences and the availability of compatible infrastructure.

In conclusion, C4FM is a versatile and user-friendly digital communication platform that continues to gain popularity among amateur radio operators and professionals alike. Its blend of quality, reliability, and flexibility ensures its relevance in the evolving landscape of digital radio technology.

Key Components of Digital Platforms

To use digital modes, operators need several key components:

1. Transceiver: The radio equipment capable of transmitting and receiving signals.
2. Computer or Mobile Device: Used to run software for encoding and decoding digital signals.
3. Interface: Connects the transceiver to the computer, often including sound cards or USB adapters.
4. Software: Applications like WSJT-X, FLDIGI, and APRSISCE/32 are popular choices for digital mode operations.

Benefits of Digital Platforms

Digital platforms offer several advantages over traditional methods:

• Efficiency: Modes like FT8 and JT65 enable reliable communication in low-power and noisy conditions.
• Versatility: Digital modes can transmit a variety of data types, including text, images, and telemetry.
• Global Reach: Internet-linked systems like D-STAR and EchoLink extend the reach of amateur radio, connecting operators worldwide without reliance on propagation conditions.
• Experimentation: Digital platforms provide an opportunity for amateurs to explore cutting-edge technologies and develop innovative applications.

Challenges and Learning Curve

While digital platforms open new horizons, they also introduce challenges. Setting up and configuring hardware and software can be daunting for beginners. Additionally, operators must learn the protocols and practices specific to each digital mode. However, the amateur radio community offers extensive resources, forums, and local clubs to assist newcomers.

The Future of Amateur Radio Digital Platforms

The future of amateur radio is likely to see even greater integration of digital technologies. Advancements in software-defined radios (SDRs), machine learning, and digital signal processing promise to further enhance the capabilities and accessibility of ham radio. Furthermore, the use of digital modes in emergency communications and disaster response demonstrates their practical importance beyond hobbyist applications.

Conclusion

Digital platforms have transformed amateur radio, merging its rich tradition with the innovations of the digital age. By adopting these technologies, ham radio operators can expand their horizons, connect with more people, and continue to play a vital role in advancing communication technology. Whether you’re a seasoned operator or a curious beginner, the world of digital amateur radio awaits exploration

The 900 MHz band is part of the UHF (Ultra High Frequency) spectrum and spans 902–928 MHz in the United States. This band is allocated as an ISM (Industrial, Scientific, and Medical) band but is also shared with amateur radio on a secondary basis. Here’s an overview of its role in amateur radio:

Characteristics of the 900 MHz Band

1. Propagation:
   • The 900 MHz band behaves similarly to other UHF frequencies but offers slightly higher attenuation due to its shorter wavelength.
   • Signals are primarily line-of-sight and can penetrate buildings better than higher frequencies like 1.2 GHz but less effectively than VHF.
2. Bandwidth:
   • The band offers a wide 26 MHz of spectrum, allowing for high-speed data applications, experimentation, and voice communications.
3. Shared Use:
   • As a shared band, amateur radio operators must avoid interfering with primary users like ISM equipment, which includes devices like cordless phones, Wi-Fi, and industrial systems.

Applications in Amateur Radio

1. Repeater Systems:
   • 900 MHz is increasingly used for amateur radio repeaters, providing coverage in urban areas. These repeaters often require specialized equipment, as commercial 900 MHz devices may need modification for amateur use.
2. Digital Modes:
   • Modes such as D-STAR, DMR, and P25 can operate in the 900 MHz range, enabling digital voice and data communication.
3. Mesh Networking:
   • Amateur radio operators use the 900 MHz band for HSMM (High-Speed Multimedia Mesh) networks, leveraging it for broadband-like applications.
4. Experimental Projects:
   • The band is popular for experimentation, including SDR (Software-Defined Radio), microwave link tests, and innovative antenna designs.

Equipment for the 900 MHz Band

• Amateur radio equipment for this band is less common than for lower bands like VHF or HF.
• Operators often repurpose commercial gear such as Motorola radios or modify ISM-band transceivers for amateur use.
• SDR platforms like HackRF or BladeRF also support the 900 MHz band, making it accessible for tech-savvy operators.

Challenges and Considerations

1. Interference:
   • The proliferation of ISM devices in the 900 MHz band can lead to interference, especially in densely populated areas.
2. Limited Availability:
   • Off-the-shelf amateur radio gear for this band is relatively rare, requiring technical skills to adapt commercial equipment.
3. Regulations:
   • Amateur radio use in this band is secondary, meaning operators must yield to primary users and comply with specific regulations.

Why Use the 900 MHz Band?

The 900 MHz band provides a unique opportunity for experimentation and communication in areas where lower bands might be congested. Its characteristics make it suitable for both voice and data applications, particularly in urban and suburban environments.

As technology evolves, the 900 MHz band is gaining popularity among amateurs who enjoy the challenge of working with higher frequencies and less conventional equipment.

Association News

IRLP and 900 MHz Repeater: Check out the new page re our connection to the Internet Radio Linking Project, our 900 MHz repeater and associated links.

The rules and regulations in this part are designed to provide an amateur radio service having a fundamental purpose as expressed in the following principles:

(a) Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications.

(b) Continuation and extension of the amateur’s proven ability to contribute to the advancement of the radio art.

(c) Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communication and technical phases of the art.

(d) Expansion of the existing reservoir within the amateur radio service of trained operators, technicians, and electronics experts.

(e) Continuation and extension of the amateur’s unique ability to enhance international goodwill.

Scientific Details of The Linen Frequency Study

In 2003, a study was done by a Jewish doctor, Heidi Yellen, on the frequencies of fabric.  According to this study, the human body has a signature frequency of 100, and organic cotton is the same – 100.  The study showed that if the number is lower than 100, it puts a strain on the body.  A diseased, nearly dead person has a frequency of about 15, and that is where polyester, rayon, and silk register. Nonorganic cotton registers a signature frequency of about 70. However, if the fabric has a higher frequency, it gives energy to the body.  This is where linen comes in as a super-fabric.  Its frequency is 5,000. Wool is also 5,000, but when mixed together with linen, the frequencies cancel each other out and fall to zero. Even wearing a wool sweater on top of a linen outfit in a study collapsed the electrical field. The reason for this could be that the energy field of wool flows from left to right, while that of linen flows in the opposite direction, from right to left. 

In an email dated 2/10/12, Dr. Yellen explained the process of this study:
“Frequency was determined by a technician named Ivanne Farr who used a digital instrument designed by a retired Texas A&M professor called the Ag-Environ machine. We had a public demonstration with an audience at internationally known artist Bob Summers home. 

“Bob Graham, the inventor, told us that his machine was created to analyze the signature frequencies of agricultural commodities to aid the farmer in determining the right time of harvest growth.  The gentleman identified signature frequencies that identified illness also and had turned to helping people get well.  Bob Graham stated that it was a ‘signature frequency of that plant’s species identity.’  The mHz is different, we were suggested that it would be the same as Rose essential oil.  

“There could be better devices so we have been looking around for more options.  There’s a device that a brilliant American agriculture scientist developed that does measure the frequency of Linen.  We have not yet acquired one but hope to soon!

“Dr. Philip Callahan, a noted physician and researcher, was able to prove the existence of this energy using plant leaves attached to an oscilloscope. About six months ago, he visited me in California and showed me a new development. He had discovered that flax cloth, as suggested in the Books of Moses [the Torah or Pentatuch], acts as an antenna for the energy. He found that when the pure flax cloth was put over a wound or local pain, it greatly accelerated the healing process. He was also using the flax seed cloth as a sophisticated antenna for his oscilloscope.  This is the instrument that he uses to determine energy of flax.”

Pgs. 19-20 of Whole Health, by Mark Mincolla Ph.D.

From: Sam Sargent <n1sfm@yahoo.com>
Sent: Wednesday, September 6, 2023, 1:36 PM
To: Clayton N1VAU Ferry; Murphy P Bob N1KWH; Jim N1CRZ Robinton; Dave Worrall; Dave Megin; Cliff Dickinson; Justin Thibeault
Subject: Testing Liberty Hill repeater 9/5/23

Hello all,  

Bob N1KWH, Clayton N1VAU & I enjoyed another pleasant B&B at T-Bones in LCI last evening.  There was lots of good conversation.  It was good to catch up.  

Among the topics thoroughly discussed was the “Liberty” repeater 147.240+ (88.5 Hz) that has been installed on the tower that Clayton owns atop Liberty Hill in Gilford, NH.  This machine is associated with the “603” radio club that Clayton & Rick Zack have established.

Hampden County Radio Association: We’ve got a Facebook page up and running for New Hampshire ARES. If there is anything that you would like me to post on the page please get it to me and I’ll take care of it. For those clubs and ARES units that I found have Facebook pages, I’ve either followed or joined your pages to link us all together. Please pass this on to your members so that they can view and participate in the Facebook page. Hopefully this outreach effort will gain some traction and interest in ARES and boost out unit membership as we definitely need some help.

What is Ham Radio?

What is Ham Radio? It’s the most fun you can have with a radio. You can talk to people around the world, and even orbiting the earth, learn about electronics and be of service to your community.

There are thousands of amateur radio organizations across our country serving over 760 thousand licensed Hams, interacting with about a million more Hams worldwide.

Contact us to learn more about our local ham radio organization.

Lakes Region Repeater Association

***Enhanced Communication with Seamless Interoperability***

____________________

Listen to our Pubic Service Announcement on

WMEK 88.1 FM WRKJ 88.5 FM WWPC 91.7 FM WWLK 101.5 FM WLKZ 104.9 FM WSEW 88.7 FM

Ham radio antenna relocation and upgrade 2020. Work on tower, installation of platform and relocation of LRRA’s antennas.

Thanks to Crown Castle,  Green Mountain Communications and the Technical Committee.

Rockin’ the Lakes Region!!

Check out Jayson’s (KB1RFS) drone shots of the tower in its current configuration. (March 2021)

Ham radio antenna relocation and upgrade 2020.

Work on the first phase of the tower project which involved the installation of a platform at 115ft and the relocation of most of the association’s antennas has been completed. During the relocation, the 2 Meter Telewave antenna was upgraded with two additional dipole bays (generously donated by several anonymous donors) and we have already seen an increase in the reach of the antenna do to its increased gain. There is still some adjustments and tweaks that need to be made to fully optimize the system post-relocation, but these are in the very capable hands of Frank/W1WU, Bob/N1EUN and the rest of the technical committee.

During the tower extension project, the safety climb cable between the pegs was replaced with a longer one to reach the top and new grommets were installed alternating with particular care to make sure the cable was not creating any mechanical noise on the tower that would affect our repeaters as it did in the past. 

The association thanks Crown Castle for going the extra mile to help keep mechanical noise on their tower to a minimum.   73!

Weather Station Project.

The tech  committee members,  with equipment donated to the association,  are working to establish a weather station at the repeater site that will eventually be remotely accessible and will provide wind speed direction indoor and outdoor temperature information for the site.   More to follow.

National Weather Servce

NWS Mission

Provide weather, water and climate data, forecasts, warnings, and impact-based decision support services for the protection of life and property and enhancement of the national economy.

NWS Vision

A Weather-Ready Nation: Society is prepared for and responds to weather, water, and climate-dependent events.