Ido Roseman's Blog

Category: radio

  • How AI Helped Me Send Pictures Through a Network That Wasn’t Meant For It

    Many years ago, I was sending high altitude balloons to the sky with cameras attached. I wanted them to broadcast these images live to the ground. The solution I used was analog SSTV which ham with good antennas could receive. I also experimented with digital images over APRS. The idea was to decentralize the reception with numerous stations already operating and bridged to the internet.

    In the past year there is a boom of local hams using Meshtastic, which is based on long range lora communication and packet relaying. I wondered if I could revisit this project using the new technology.

    TL;DR it’s not that easy

    (more…)

  • How to Use an All-Band Receiver to Listen to Airplane Pilot Communications with Ground Controllers

    In the world of aviation, communication between pilots and air traffic controllers is crucial for safe and efficient operations. For aviation enthusiasts & radio hobbyists, listening in on these transmissions can be fascinating and insightful for many reasons,

    While it may be tempting to use a simple off-the-shelf walkie-talkie style receiver or scanner to listen in on air traffic communications, doing so in or near an airport can be problematic. More importantly, airport security and aviation authorities generally view the use of such devices with suspicion. In some cases, they may even be prohibited in certain areas of an airport due to concerns about security and interference with official communications. even if your intentions are pure and have the proper equipment, trying to explain that to a concerned security officer can turn to be a headache.

    enter the All Band Receiver.

    (more…)

  • ham radio logbook fit for the 21st century

    It all started with a simple whatsapp messages on a whatsapp group

    hmmmm…. that’s a nice callsign…. have I’ve worked him before?

    of course I had all the information available at my fingertips, if I was near my computer. but I had to get of the couch for this. if only I had my logbook as an iphone app, I thought

    Since I wrote my own logging program, it shouldn’t be too hard to port it into a mobile app, or so I thought.

    (more…)

  • midi based controller for sdr-console

    This is a quick project that i wanted to build for some time, and since I had the needed parts from another project, i was able to complete in a short time.

    Using SDR software has a lot of advantages, you get waterfall views, multitude of operation modes, and it’s all for free. but for the hardcored ham you get to miss the feeling of actual knobs and dials.

    fortunately there is a simple way to connect a physical device to control some of the software functions.

    (more…)

  • הלווין הקאטרי QO-100

    כמו חובבי רדיו רבים גם אני סובל מתנאי התקשורת הירודים ששוררים בשנים האחרונות. ומכיוון שאין לי סבלנות לחכות שנים עד שמזג האויר בשמש ישתנה, התחלתי לחשוב על אלטרנטיבות, כמו לנסות לקלוט לוויני תקשורת. קניתי אנטנה טובה והתחלתי לנסות לקלוט. די מהר הבנתי שזה לא בשבילי. הלווינים עוברים בשמיים במועדים בודדים, ולנסות לכוון אליהם את האנטנה באופן ידני זה על סף בילתי אפשרי, לפחות ליכולות המוגבלות שלי. אבל אז שמעתי על שיגור הלווין הקטארי, הלוא הוא אוסקר-100

    ההבדל בינו לבין הלווינים הקודמים הוא שהוא גאו-סטאציונארי. כלומר מהירות הסיבוב שלו סביב כדור הארץ זהה לזו של כדור הארץ עצמו, ולכן הוא נראה לנו במיקום קבוע בשמים מעלינו. כך עובדים לוויני תקשורת רבים, לדוגמא שידורי הטלוויזיה של yes.

    אחרי כמה ימים של הפעלה אני ממש מרוצה. התקשורת נעימה וטובה, האנשים דברנים ולא רק שם כדי להוסיף ווי למאגר התעודות שלהם. בפחות משבוע עשיתי יותר מ20 קשרים עם אנשים מהודו ועד ברזיל, נפוצים כמו אירופה ונדירים כמו סודן.

    (more…)

  • פאנאדפטר לkx3

    אחת התוצרים של מעבר יצרני מקמשים לטכנולוגית sdr היא תוספת של תצוגת ״מפל מים״ waterfall נוחה שמראה באופן ויזואלי את הנעשה בתדרים הסמוכים. גם בעבר היו יחידות כאלו, אך מחירם היה גבוהה.

    אני משתמש ותיק בkx3 שלצערי, משיקולי מחיר אני מניח, יחידת תצוגה כזו באה כמכשיר חיצוני (px3) בעלות גבוהה. לשמחתי ראיתי שניתן לבנות תצוגה כזו בשבריר מהמחיר המקורי

    (more…)

  • installing direwolf on macOS

    I’ve been using APRS quite alot recently and wanted to install my favorite igate program “direwolf” on my macbook pro. unfortunatly, while direwolf is able to run on OSX, it does not come with updated support and documentation. so here’s what I’ve done.

    (more…)

  • why i decided to write yet another ham radio logbook software

    TL;DR It’s all about the User eXperience, design and making software fit you, and not the other way around.

    I’m an amateur radio operator. as all hams, we are required to save a log of our contacts with other people. besides the legalities, it’s nice to have a record of places & people I’ve talked with. when I’ve started my hobby, some 30 years back, I received a paper logbook which I’ve been using untill recently, and I’ve been very happy with it.

    I’ve been thinking of using a computerized logbook software, but to be honest, I really had no incentive. pen and paper were good enough for me. plus, the ones I’ve tried to use (out of the thousands out there) left me with a horrible experience. i consider my self as a savvy computer user, but most of the programs I’ve tried had a “designed by an engineer” look and feel, which in this day and age is simply a crime.

    (more…)

  • DIY HF Antenna Analyzer

    some time ago i got a nice deal on a buddipole antenna. I already had an alexloop which i was very happy with, but I could not resist the temptation of a “real” dipole that could take the full 100W from my rig. so i went online and ordered one.

    after i got the package  i went on and setup the rig and antenna, and it worked ok. but i wasn’t happy and wished for more… it took a lot of time to assemble and result were on par of the alexloop.

    At the last hamvention i had a chance to talk to the buddipole engineers at their booth. the first question they had was “did you checked it with an antenna analyzer” ? “no”, i’ve replied. “so you should” they said. and it sounded like a solid advice. now i had a plan…

    (more…)

  • Hamvention 2017

    I had an opportunity to visit the Hamvention in Dayton OH this year, so I jumped at the opportunity. to be honest I didn’t know what to expect. I had my fair share of professional trade shows in the US, and at a first glance, I fitted the description: booths with manufacturer displaying the latest and greatest, classes with top notch lectures and all those kind of things.

    (more…)