Schaumburg Amateur Radio Club

10/09/2026

📱 Try your next SARC net with QSO One!

Your Windows laptop or Android phone could become another way to join the conversation. QSO One is a free app for AllStarLink, EchoLink, and several digital voice networks—without building your own Raspberry Pi node or buying a hotspot.

First, have your amateur radio callsign and the required network accounts ready. Then, check SARC’s published connection details, listen, and join when net control invites check-ins.

Our new article explains the setup, account requirements, and SARC connections to try. It also clarifies an important detail for Fusion users: YSF reflectors and WIRES-X rooms use different connection paths.

👉 Read the full article, then try QSO One on your next net!
https://www.n9rjv.org/2026/10/qso-one-ham-radio-without-the-hardware/

Thanks to Paul Burkett, KD9FMN, for suggesting this operating idea.

Have you tried QSO One? Share your experience or setup questions in the comments!

Here is a practical operating idea for SARC members: try your next club net from a Windows computer or Android phone. QSO One brings several amateur radio voice networks into one free app, offering another way to stay involved when you are away from your station.[1] Post idea from: Paul Burkett, KD9...

10/07/2026

🍂 Is your ham radio station ready for fall?

October is a good time to check your antennas, test backup power, and enjoy some time on the air.

SARC’s October Ham Radio Station Guidance offers practical steps for newer hams and experienced operators alike:

📡 Prepare your 40- and 80-meter antennas while keeping the higher bands available.

🔋 Check power connections and measure voltage during transmission.

📊 Learn what your SWR readings and antenna analyzer can tell you.

🎙️ Explore October operating opportunities, including the Illinois QSO Party, School Club Roundup, and CQ World Wide SSB.

Start with one manageable project. Record your results. Then make a few contacts and see what you learn!

👉 Read the October station guide:
https://www.n9rjv.org/2026/10/october-ham-radio-station-guidance/

Have a question or a measurement you would like help understanding? Bring it to a SARC meeting. Visitors are welcome!
https://www.n9rjv.org/activities/monthly-club-meetings/

What station project is on your October list? Tell us in the comments—and share this post with a fellow ham.

Put your fall antenna plans into practice, and use October operating events to learn how your station performs. SARC

09/28/2026

📻💻 How can a weak digital signal survive noise—and why can’t every file be compressed forever?

The answers begin with the work of mathematician and engineer Claude Shannon.

In 1948, Shannon established mathematical limits for representing information and transmitting it reliably through noisy communication channels. His ideas now influence data compression, cellular systems, computer networks, error-correcting codes, and amateur radio digital modes.

SARC’s new article explains three foundational results:

🔹 Source Coding Theorem: Predictable information can be compressed, but lossless compression cannot beat the source’s entropy on average.

🔹 Noisy-Channel Coding Theorem: A noisy path can still carry digital information with an extremely small error probability when the transmission rate remains below the channel’s capacity, and suitable coding is used.

🔹 Shannon–Hartley Theorem: Bandwidth and received signal-to-noise ratio place an ideal upper limit on how quickly information can travel through a channel.

The article connects the theory to practical examples, including:

📊 Calculating Shannon entropy
🗜️ Understanding Huffman and DEFLATE compression
📶 Converting signal-to-noise ratios from decibels to linear values
📡 Estimating the capacity of a 3,000 Hz radio channel
📱 Seeing how modern cellular systems use error-correcting codes
🖥️ Exploring why FT8 can recover short messages under weak-signal conditions

For example, an ideal 3,000 Hz channel with a 10 dB signal-to-noise ratio has a calculated Shannon–Hartley capacity of approximately 10,378 bits per second. That is a theoretical limit under specific assumptions—not a promise that a particular modem will reach that speed.

The article also explains an important digital-radio distinction:

Source coding removes predictable redundancy. Channel coding adds carefully designed redundancy so the receiver can detect or correct errors.

You do not need to master every proof to use Shannon’s ideas. Start with one calculation, one digital mode, or one question:

How much information is in the message, and how much can the channel reliably carry?

Read the complete article, follow the worked examples, and try the suggested SARC learning activities:

https://www.n9rjv.org/2026/09/shannons-theorems-from-data-compression-to-reliable-ham-radio/

Which part interests you most: data compression, error correction, channel capacity, or weak-signal digital radio?

Explore how Shannon’s theorems connect data compression, 5G, and weak-signal ham radio through clear explanations and worked calculations.

09/28/2026

Brenda Fruhauf's pics of the 2026 Belvidere Hamfest. Visit SARC's Radio Hill Gazette for the full article and pics. https://www.n9rjv.org/2026/09/belvidere-hamfest-2026-sarc-members-selling-tables-and-radio-conversation/

09/26/2026

🧮📻 What connects ancient counting marks, Babylonian mathematics, zero, geometry, calculus, computer logic, and a 14 MHz radio signal?

They are all part of the long, global history of mathematics.

Mathematics did not begin with one person or in one place. It developed across many cultures as people learned to count, measure land, study the sky, solve equations, describe motion, organize information, and communicate ideas.

SARC’s new article follows that remarkable journey from early quantity and pattern recognition to modern research.

Along the way, it explores:

🔹 Mesopotamian place value and base-60 calculation
🔹 Egyptian fractions and practical geometry
🔹 Greek proof and Euclid’s Elements
🔹 Chinese algorithms, negative numbers, and equation systems
🔹 Indian decimal notation, zero, trigonometry, and infinite series
🔹 Algebra and mathematical scholarship across the Islamic world
🔹 Maya numbers, Inca khipu, African geometric traditions, and Polynesian counting
🔹 Calculus, probability, matrices, topology, and set theory
🔹 Logic, computation, information theory, chaos, and computer-assisted proof

The article also brings the story back to amateur radio.

Mathematics helps operators understand frequency, wavelength, oscillation, signal behavior, noise, coding, and the limits of reliable communication. Claude Shannon’s information theory, for example, created a mathematical framework for studying messages sent through noisy channels.

A practical example connects a frequency display to a physical wavelength:

Wavelength in meters ≈ 300 ÷ frequency in megahertz

At 14 MHz, the free-space wavelength is approximately 21.4 meters. Doubling the frequency to 28 MHz cuts the wavelength roughly in half.

That calculation is not a finished antenna design, but it is an excellent example of how mathematical history connects to something familiar in the radio shack.

You do not need advanced mathematics to begin. Choose one culture, one mathematician, one branch of mathematics, or one simple calculation—and follow your curiosity.

Read the complete illustrated history:

https://www.n9rjv.org/2026/09/the-history-of-mathematics-from-early-counting-to-modern-research/

Which mathematical idea has helped you most in amateur radio: wavelength, decibels, impedance, probability, signal processing, or something else?

Choose one mathematical idea, try the wavelength exercise, and bring a question to a SARC meeting. SARC - Schaumburg Amatuer Radio

09/24/2026

📡 Behind the music, food, parade, and crowds at Septemberfest was a team helping important information move clearly and efficiently.

During Schaumburg Septemberfest 2026, SARC volunteers provided organized public-service communication support across all three days of the celebration.

Members served as additional eyes and ears at assigned locations, maintained contact with Net Control, passed along observations and requests, and worked within the event’s established command structure. Their role was not to replace police, fire, medical, or Village personnel. It was to support those teams through clear, accurate, and disciplined radio communication.

The club’s message displayed above the festival captured the spirit of the effort:

📻 Communicating
📚 Learning
🤝 Giving back
🎉 Having fun

Thank you to Howard Mitchell, KD9WSV, for coordinating the documented preparations; Eliot Libner, N9EPA, for stepping forward when the final volunteer assignment needed to be filled; and every SARC member who gave time, equipment, and operating skill to support the community.

Thanks also go to Village staff, event organizers, public-safety personnel, and fellow volunteers who helped make Schaumburg’s 55th Septemberfest possible.

As SARC celebrates its 50th anniversary, this partnership is a powerful reminder that amateur radio is about more than making contacts. It is also about teamwork, preparation, friendship, and service.

Read the complete story and learn how SARC supported Septemberfest 2026:

https://www.n9rjv.org/2026/09/sarc-septemberfest-community-service/

Interested in using your amateur radio skills to help the community? Join SARC and take part in a future public-service activity.

Discover how SARC prepared to support Schaumburg Septemberfest 2026 through amateur radio, volunteer teamwork, and a 50-year tradition.

09/20/2026

📻 A proud Septemberfest partner. A proud tradition of serving Schaumburg.

The big screen captured SARC’s spirit perfectly: communicating, learning, giving back, and having fun!

Behind that message were club members who stepped forward to support the 2026 Schaumburg Septemberfest through amateur radio and volunteer teamwork. From organizing credentials and equipment to filling the final open assignment, their preparation helped turn a commitment to service into a team ready to help.

Thank you to our volunteers, coordinators, and Village partners! As SARC celebrates 50 years, your willingness to give back keeps that tradition moving forward.

👉 Meet the people and discover the preparation behind the partnership in “Behind the Celebration: SARC’s Role in Septemberfest 2026.”

https://www.n9rjv.org/2026/09/sarc-septemberfest-community-service/

Interested in ham radio? Come meet us—curiosity is welcome, and you don’t need a license to visit a club meeting!

Discover how SARC prepared to support Schaumburg Septemberfest 2026 through amateur radio, volunteer teamwork, and a 50-year tradition.

09/18/2026

📻 Mercury vs. VARA HF: Which belongs in your shack?

Mercury’s free, open-source approach is getting attention. But before you switch, there’s one question worth asking:
Will it connect to the station you want to reach?

Our SARC comparison explores:

• The advantages and tradeoffs of each modem
• Windows, Linux, and Raspberry Pi considerations
• What compatibility means for Winlink and chat
• A practical test you can try with another ham

Whether you’re planning your first digital message or experimenting with a new setup, start with the details that matter.

👉 Read “Mercury vs. VARA HF: Pros, Cons, and Practical Choices for SARC.”
https://www.n9rjv.org/2026/09/mercury-vs-vara-hf/

Which would you like to try—and would you use it for email, chat, or file transfers?

Compare Mercury and VARA HF, understand compatibility, and plan a practical SARC test of digital messaging, and setup effort.

08/20/2026

📡 AntSDR T510 AI: Wideband SDR Meets Edge AI

What could you build with direct RF input coverage from 1 MHz to 6 GHz, up to 2 GHz of baseband bandwidth per channel, eight synchronized ADC channels, eight DAC channels, an AMD RFSoC, and an integrated NVIDIA Jetson computing module? The pre-launch AntSDR T510 AI is designed for high-speed signal capture, multichannel processing, spectrum analysis, recording, and AI-assisted wireless experiments.

SARC’s new article explains how the RFSoC and GPU divide the work, what tools such as GNU Radio, SoapySDR, WaveSight, Python, and C++ may bring to the platform, and how members could explore synchronized receivers, antenna comparisons, signal classification, timing experiments, FPGA processing, and receive-only spectrum demonstrations.

The project is still listed as “Coming Soon,” with no confirmed price, campaign date, or shipping schedule. Published details may change. Also, wide frequency coverage does not authorize transmission throughout that range—begin with receive-only experiments, and test any transmit work into a suitable dummy load under the control of a properly licensed operator.

How would you use the ANTSDR T510?
https://www.n9rjv.org/2026/08/antsdr-t510-1-mhz-to-6-ghz-and-up-to-2-ghz-baseband-bandwidth/

08/16/2026

💻🔧 Ready to move from writing code to controlling real hardware?

An STM32 microcontroller can read switches and sensors, control LEDs and displays, measure voltages, keep time, and exchange data with other equipment. Those same skills can become the foundation for future amateur-radio projects.

SARC’s new article introduces “Learn STM32 Microcontroller Programming—Full Course for EE/CS Students and Beginners Version 3.”

You do not need to be an electrical engineering or computer science student to begin. This self-paced YouTube course includes approximately 11 hours of instruction and 34 projects, starting with the development environment and basic programming before moving into practical hardware work.

The course explores:

🔹 STM32CubeIDE setup and project creation
🔹 Programming, debugging, and troubleshooting
🔹 LEDs, push buttons, and GPIO
🔹 LCD displays and formatted data
🔹 Analog-to-digital conversion
🔹 Timers, counters, PWM, and interrupts
🔹 I²C and USART communications
🔹 KiCad printed-circuit-board development
🔹 Comparisons involving AI-generated code

For amateur-radio builders, these skills could eventually support projects such as a station-status display, battery monitor, environmental sensor, practice keyer, telemetry display, rotator interface, antenna-switch controller, or test fixture.

Start small. Flash a known program that blinks one LED. Then read a push button or send a short serial message. Change one item at a time, test the result, and record what you learn.

One important reminder: STM32 is a large family of chips and boards—not one interchangeable device. Confirm the exact board, microcontroller, programmer, pinout, voltage limits, parts, and software required for each lesson.

Keep beginner projects separate from your radio equipment.
Never connect a microcontroller pin directly to an antenna feed line, push-to-talk circuit, keying line, or transceiver accessory port without the correct buffering, protection, level conversion, or isolation.

Read the complete SARC guide and begin your first verified STM32 project:
https://www.n9rjv.org/2026/08/learn-stm32-microcontroller-programming/

What amateur-radio accessory would you like to build with a microcontroller?

Explore a project-based STM32 programming course and learn how embedded-system skills can support practical amateur-radio experiments. SARC