Starting at 4pm local time Saturday Jan 10 John KK6GUK and my self will be attempting a 24 hour 30 park activation.
We will be starting in Reedsport and working our way south down into Curry County.
We will post parks and frequencies as we move from park to park on the clubs FB messenger group and by email as we have time.
For those of you who do not have hf and want to help us get our activations, especially on Saturday night, we will be calling cq on 146.52 simplex occasionally. We will resort to UHF 446.000 as well if it gets hard to get the required 10 contacts per park.
We will be monitoring the SWORA linked VHF repeater system as well.
The best way to follow us is by using the HamAlert app on your smartphone using my call N6BLU or John’s call KK6GUK as triggers or on the Parks on the Air website.
This will be a fast paced attempt and band conditions may not be ideal due to some solar activity so if you have some time to try and hunt us.
We plan on starting on 20 meters and moving to 40 meters in the evening but will try other bands like 15 or 17 meters if 20 meters isn’t cooperating. If 10 meters is open on Sunday we’ll try that too at some point.
Hope to hear you on the air.
Gary N6BLU
Interested in Amateur Radio? Concerned about Emergency Communications in general?Would you like to learn about specific aspects of Ham Radio such as licensing? Winter Field Day is a great way to connect with the Coos County Radio Club.
Everyone Welcome!
The Winter Field Day Association (https://winterfieldday.org) promotes portable emergency communications in winter environments because freezing temperatures, snow, ice, and other hazards make operating ham radio gear difficult.
Coos County Radio Club, in conjunction with the Coos County Amateur Radio Emergency Service (ARES) will gather for WFD operations at the the Powers High School, a designated Red Cross shelter.
WFD activities help participants improve emergency preparedness by enhancing radio operational abilities in adverse conditions. Contacts between amateurs are made on the HF, VHF, or UHF bands by voice (SSB), CW, and digital modes.
See Coos Radio Club WFD 2026 Flier for local details.
If you or anyone you know is interested in attending an Amateur Extra Class licensing course, please pass along the following information, and feel free to publicize it with your radio club or any group you feel would benefit.
A free, weekly, live, Amateur Radio Extra Class Licensing course on Zoom will begin on Thursday, January 15, 2026, and will run through Thursday, March 26. There will be 11 sessions. The three-hour sessions will start at 6:30 PM Eastern Time and will also be recorded. These are the classes that we have been holding for years sponsored by the Amateur Radio Club of the National Electronics Museum.
Note: Attendees should hold (or be studying for) the General Class Amateur Radio License.
Please publicize this with anyone that you think would be interested. Those wishing to sign up should email roland.anders.
We have overlapping mailing lists, so if you received a duplicate of this message, thanx for your understanding.
Speculation on the effect of cascading space junk collisions on Amateur Radio.
“The Kessler Syndrome is a scenario proposed by NASA scientists Donald J. Kessler and Burton G. Cour-Palais in 1978. It describes a situation in which the density of objects in low Earth orbit (LEO) becomes so high due to space pollution that collisions between these objects cascade, exponentially increasing the amount of space debris over time.”
What if satellite communications were suddenly squeezed off. Internet, TV and Cellular telephone backbones choked or disconnected. Could it portend a fall-back to HF radio? How handy would Amateur radios become?
SpaceX recently had a satellite go silent then quickly drop several miles. It’s on an uncontrolled trajectory estimated to de-orbit (demise) in weeks. Analysis indicates it exploded.
On December 17, Starlink experienced an anomaly on satellite 35956, resulting in loss of communications with the vehicle at 418 km. The anomaly led to venting of the propulsion tank, a rapid decay in semi-major axis by about 4 km, and the release of a small number of trackable…
LeoLabs is a commercial group that tracks as many things in orbit as it can see with private space radar. They first estimated the debris at tens of shards. The guess has increased to some thousands.
Zoom in/out, turn the globe. Click on objects in the tool. It lists what they are.
Other experts offered the event didn’t seem like a spontaneous onboard failure, but almost certainly an impact. Perhaps an impact that ignited a fuel explosion propelling the apparatus into a decaying orbit. The speculation centers on the high degree of SpaceX orbiter reliability.
The visualization also shows debris regions. Precursors to an as yet narrowly avoided, Kessler Syndrome?
Question: How long after a Kessler Syndrome event would it be too dangerous for people to fly into space?
Answer*:
If a full Kessler event (a runaway chain reaction of collisions) occurred today, the answer depends entirely on how high the debris orbits earth. Space isn’t a single “room”; it’s a series of shells, and each shell has a different “cleaning cycle.”
Because there is no “janitor” in space, we rely on the Earth’s atmosphere to drag debris down. The higher the altitude, the thinner the air, and the longer the debris stays.
1. Low Earth Orbit (LEO) – Under 500 km
Safety Timeline:1 to 10 years.
Context: This is where the International Space Station (ISS) and Starlink satellites live. Because there is still a tiny bit of atmosphere here, “drag” acts like a slow brake.
Result: In a Kessler event, this region would become a “death zone” almost instantly. However, within a decade, most of that specific debris would spiral down and burn up in the atmosphere, making it potentially safe for humans to fly through or inhabit again.
2. Mid-LEO – 600 km to 1,000 km
Safety Timeline:Decades to Centuries.
Context: This is the most dangerous “sweet spot” for Kessler Syndrome. It’s crowded with old weather satellites and rocket bodies, but the atmosphere is too thin to provide quick cleaning.
Result: Debris at 800 km can stay in orbit for over 100 years. If a full cascade happened here, this shell of space would be effectively closed to human life for multiple generations.
3. High Orbit – Above 1,000 km
Safety Timeline:Millennia (1,000+ years).
Context: At these heights, atmospheric drag is non-existent.
Result: Any debris created here is essentially permanent on a human timescale. A Kessler event at this altitude would create a “shell” around Earth that could remain lethal for thousands of years, potentially trapping humanity on the planet until we developed the technology to actively “harpoon” or laser-sweep millions of tiny fragments.
The “Hollywood” vs. Reality Factor
Contrary to the movie Gravity, a Kessler event doesn’t happen in 90 minutes. Experts describe it more like a “slow-motion train wreck.”
The First Days: You might lose 10% of satellites.
The Following Decades: The debris from those 10% hits others, creating more fragments. The “syndrome” is the period where the amount of junk is growing faster than the atmosphere can remove it.
Could we still leave Earth?
Even in a “full” Kessler scenario, humans could likely still launch through the debris to go to the Moon or Mars. A rocket only spends a few minutes passing through the danger zone. It’s like running across a busy highway—it’s incredibly risky and requires perfect timing, but you aren’t “stuck” forever. However, staying in orbit (like on a space station) would be impossible because you are a stationary target in a shooting gallery.
The FCC allocated a new chunk of the 60m band to amateurs in the US.
The action opened 5351.5 – 5366.5 kHz (60 meters) to the amateur service on a secondary basis with a permitted power of 9.15 watts ERP.
The Commission also authorized amateurs to continue using four existing channels outside of the 5351.5 – 5366.5 kHz band centered on 5332, 5348, 5373, and 5405 kHz on a secondary basis with a permitted power of 100 watts ERP.
There are no antenna restrictions but antenna gain must be used to calculate ERP.
General class license holders and above will receive the new privileges 30 days after publication to the National Register.
As club members may be aware, there are no DMR VHF repeaters in the Coos County area. (At least to this editor’s knowledge.) If your HT has DMR mode, that mode is basically useless on the local air unless you have a friend and both radios are programmed correctly to use DMR.
However! DMR is a great way for Technician class operators to make contacts around the world. If you’re curious about DMR, it’s easy to jump in with nothing more than a web browser.
What is DMR? Well, as an amateur radio digital mode, the encoding improves weak signal reception. Also the packets are designed to be sent over IP networks (E.g the internet, VoIP.) On basic VHF/UHF FM radio, communication is “simplex” – one party talks at a time. DMR is duplex – allowing two simultaneous speakers. It’s done with TDM. Time Domain Multiplexing – just like analog telephones or POTs. “Plain old Telephone Service.”
“DMR (Digital Mobile Radio) in ham radio is a digital voice standard, adapted from commercial use, that allows two simultaneous conversations (time slots) on a single frequency, offers clearer audio, extended battery life, text messaging, GPS, and connects repeaters via the internet, providing enhanced features over traditional analog radio, primarily using Tier II for licensed users.” Wikipedia. (More about Tiers follow the link…)
BrandMeister and TGIF DMR are carrier networks (requiring call sign login to chat) are the top DMR services. Users that login with their Call Sign and have registered for a DMR ID at RadioID.net with can converse on the DMR network.
Covering them both is a website where visitors can view the map and listen (only) to talk groups on either system – with out a call sign. See DMRMap.APP
Brandmeister Talk Group 3141 (shown above) links the internet to the West Oregon DMR repeater network. Check out the “Happy Hour” Net at 5PM daily.
DMR is used on the amateur radio VHF and UHF bands, started by DMR-MARC around 2010. The FCC officially approved the use of DMR by amateurs in the US in 2014.
In amateur spaces, Coordinated DMR Identification Numbers are assigned and managed by RadioID Inc. Their coordinated database can be uploaded to DMR radios in order to display the name, call sign, and location of other operators.
Internet-linked systems allow users to communicate with other users around the world via connected repeaters, or DMR “hotspots.” Such systems are often based on the Raspberry Pi single-board computer.
There are currently more than 5,500 repeaters and 16,000 “hotspots” linked to the BrandMeister system worldwide.
As always! Let us know what you think. Comments and suggestions welcome. More information is available.
DMR Simplex
Yes, amateur radio DMR can operate transceiver to transceiver in a mode called simplex.
Here’s a breakdown:
Simplex Operation: In DMR simplex, two radios communicate directly with each other on the same frequency without the use of a repeater or an internet-connected hot spot. This is also sometimes referred to as “Direct Mode.”
Repeater/Network Operation: This is the most common way amateur DMR is used. A DMR repeater or personal hotspot links users to a wider network (often via the internet, like BrandMeister or Phoenix), allowing for local, regional, or even worldwide communication using Talk Groups. This is a form of duplex operation where the radio transmits on one frequency and receives on another.
Key Points for DMR Simplex: Settings Required: Unlike simple analog FM simplex, DMR simplex requires both transceivers to have the same frequency, Color Code, and Talk Group ID programmed.
Color Code: A digital equivalent to a CTCSS/PL tone, used for system access.
Talk Group ID: Typically Talk Group 99 is designated for simplex use in amateur radio, though any shared Talk Group ID would technically work if all parties are programmed to it.
Range: As with any simplex mode, the range is limited by terrain, power output, and antenna efficiency—it’s strictly line-of-sight or slightly beyond.
TDMA: Even in simplex, DMR uses its Time-Division Multiple Access (TDMA) structure. On some radios, a transmission in simplex mode may use both time slots, while on others, it might only use one. However, the requirement is that both radios must be programmed to the same time slot (e.g., Slot 1 or Slot 2).
So, while DMR is famous for its wide-area networking through repeaters and hotspots, it absolutely maintains a direct, radio-to-radio simplex capability for local communication.
That is a great question. The DMR radio market is very active, especially for amateur radio operators. The radios available can generally be split into three main categories: Feature-Rich Handhelds (HTs), Budget-Friendly Handhelds, and Mobile Radios.
Here is a list of popular and well-regarded DMR-capable amateur radios across those categories:
📻 Popular Handheld Radios (HTs)
Handhelds are the most common entry point for DMR. They are portable and generally dual-band (VHF/UHF).
Category
Brand/Model
Key Features/Notes
Feature-Rich/Best Value
AnyTone AT-D878UVII Plus
Widely considered the most popular DMR handheld. Offers Dual-Band, Dual-Mode (Analog/DMR), built-in GPS, Bluetooth PTT, and supports a massive contact list (up to 500,000).
Alinco DJ-MD5XTG
Highly capable DMR HT, often sharing similar internal firmware with Anytone. Available with GPS and APRS support.
Budget/Entry-Level
Radioddity GD-88
Dual-Band, GPS/APRS, and is well-regarded for its cross-band repeat feature and large contact list capacity.
Retevis RT3S / TYT MD-UV380/390
Very popular and affordable starting radios. They are often recommended for use with the OpenGD77 third-party firmware, which greatly enhances their features and usability for amateur radio.
Baofeng DM-1701
One of the most budget-friendly DMR radios, also frequently upgraded with the OpenGD77 firmware for better performance.
Commercial Brands
Motorola XPR Series
High-quality commercial radios (e.g., XPR 6550, XPR 7550) that are often available used. Known for superior build quality and audio, but often require commercial programming software (CPS) and may have limitations on channel/contact capacity for ham use.
Hytera PD Series
Commercial-grade, known for ruggedness and reliability.
🚗 Popular Mobile Radios
Mobile radios are typically higher power (20W–50W) and designed for use in vehicles or as base stations.
Brand/Model
Key Features/Notes
AnyTone AT-D578UVIII Plus
Extremely popular Dual-Band/Dual-Mode mobile radio. Features high power (50W), built-in GPS, Bluetooth, and often includes Full Duplex capability (allowing you to talk and listen simultaneously like a phone call on V/U).
Radioddity DB25-D
A compact mini mobile radio, Dual-Band, Dual-Mode, with GPS/APRS support. A good option for smaller vehicles.
Retevis RT90
A full-power (50W) dual-band DMR mobile radio with GPS and dual-mode functionality.
Motorola XPR 5550e
Premium commercial mobile radio, often used in amateur radio for its quality, though it requires specific programming for ham use.
What to Consider When Choosing
Codeplug Complexity: DMR radios require a “Codeplug” (the configuration file) to be programmed with channels, talkgroups, and contacts. Radios like the AnyTone 878UVII Plus are popular because their software is relatively well-documented and widely supported.
GPS/APRS: Many amateur DMR radios now include built-in GPS to support APRS (Automatic Packet Reporting System) over the digital channel, allowing your location to be tracked.
Firmware (OpenGD77): For certain budget radios (like TYT/Retevis), installing the OpenGD77 custom firmware is highly recommended by the ham community to unlock a vastly improved user experience and features.
Analog/DMR (Dual-Mode): All radios listed above support both Analog FM and Digital DMR modes, which is essential for working both legacy FM repeaters and the digital network.
Do you have a specific budget or desired form factor (handheld or mobile) in mind that I could use to narrow down the best recommendation for you?
Coos County Radio Club 