Archive for the ‘ham radio’ Category
Five-band HF Linked Dipole [updated January 2025]
An improved build
This antenna was first described in the November-December 2023 Communicator. After a year of using it, I’ve developed some improvements. - Updated January 2025
I appreciate inexpensive but effective antenna design. Sure, you can spend hundreds of dollars to buy a multiband antenna for POTA or GOTA but they are so simple to build, why would you want to? You can enhance your skills and communication capabilities by constructing custom antennas.
One popular and versatile option is the multi-band HF dipole antenna often called a segmented or linked dipole. This antenna design allows for effective communication across multiple HF bands by connecting or disconnecting sections along its length making it an inexpensive asset for ham radio operators, particularly outdoors enthusiasts and those needing a light, packable wire antenna that can be erected almost anywhere, and with good results—better than an end-fed, because each segment of the antenna is pre-tuned during construction, and can be used safely even when no antenna tuner is available.
Ideally it is hung from a pole or tree branch at 20 feet (6m) as an Inverted V, with the center point high and the dipole legs spread at least 110-120 degrees. I have worked the globe with this set-up on sideband and 20 Watts.
| Oly one side of the dipole is shown |
~ John VE7TI
A different kind of Foxhunt
Suitable for the urban fox
From the January-February 2025 SARC Communicator
The last few months, I've been thinking about a different way to do a Foxhunt. My vision was to have a Foxhunt available whenever you want, especially this time of year. Not everyone lives in town, and everyone's busy shopping and might not be able to dedicate an afternoon on a specific day for a group search. But what if the fox kept calling you out for a few minutes here and there, whenever you had a chance? No pressure, just try it out and see what you can find with your gear, experimenting with different antennas to get the best results. Go get that Fox!
Where to start with my build? You guessed it: Google and YouTube. The first step was to make a Fox using things I had in my toolbox. I got a Baofeng radio, Arduino UNO, batteries, a waterproof box, and a Drok buck converter. Simple enough, right?
I first searched using Miss Google and came across this: https://www.hackster.io/nfarrier/auto-keyer-for-radio-fox-hunting-e89b99 "Cool, I can do this," I thought, so I did. After putting it all together, I programmed the Arduino UNO using the Arduino software with the code from that website. I set up the CW message, and everything tested just fine. My vision was starting to come true!
I could hear it from the east and west side of town. All was good darn... a few days later I couldn't hear it anymore until I was right beside it. I took the Fox home and discovered the TX (transmit) wasn't putting out power anymore, even though the battery was still good. My Fox SX5 Mosfet transistor must have failed. It must have been spending too much time in TX mode. So, I replaced the radio and changed the transmit message, reducing the time by almost 50 percent.
There goes the fox hunt, second radio blown. How disappointed you all would be! I talked to a fellow ham about Baofeng radios. He uses them more often than me, and he showed me in the manual that the duty cycle is very small, 03/03/54 minutes (RX/TX/Standby). My fellow ham had a spare radio he wasn't using, so I bought it from him.
I did a few more programming changes to adjust the duty cycle. I also decided to add "MORE POWER!" (à la Tim Allen) So, I added a second Makita battery for a longer stay in the den.
I relocated the fox to be closer to home, just because I know I'll need to replace the batteries in a few days. For those of you in the area, I hope you all get a chance to find the Fox.
Happy Fox Hunting! 73,
~The Silver Fox VE3BQM
Hams meet Marines
A special event station from The Netherlands
This is an HF activity on January 23 from PA25MC, which will be on the air for just one day to introduce Marines to the world of ham radio. They will try to use as many HF-bands as possible on SSB. They remind us to please remember that Amateur procedures are new to them, but will do everything to get them up to speed quickly.
Marines are used to speaking English but naturally keep their communications short. The organizers would really appreciate it if you contribute to a successful event by connecting with them!
PA25MC is organized and supported by PI4VBD, the club station of the Royal Army. Their station will always comply with the user regulations and regulations for radio amateurs and has no military function.
QSL info for PZ5JT
Erroneous Prepper Frequency Lists
Many “emergency frequency lists” showing up on the internet are a hodgepodge of frequencies scraped from various sources and assembled into what looks like a credible list. Some of these frequencies are useful, but too many are misleading and perhaps even dangerous. These lists gloss over training and licensing issues, as described here: The Talisman Radio.
Many of these lists are generated by copying other prepper lists or scanning various sources for “emergency frequencies.” Even this Wikipedia page about international distress frequencies includes some of this misinformation.
Important Disclaimer: People often point out that in many jurisdictions, a citizen without a radio license for a specific frequency can still make a call in case of a true emergency (usually defined as potential loss of life or property). This may be true, but it is generally not a good emergency communications strategy: See The Talisman Radio. Most of these lists do not address the issue of radio licensing at all, which is very misleading.
Here is a recent FCC action to consider: The FCC has ruled that a ham radio operator in Idaho must pay a record $34,000 penalty for interfering with wildfire communications on 151.145 MHz. This is a US Forest Service frequency not authorized for amateur radio licensees. So don’t be transmitting on unauthorized frequencies.
Misleading Frequency Lists
One of the worst frequency lists is shown here by Stryker Radios. This “Ham Radio Emergency Frequencies” list shows 29 frequencies, but only two are in the ham bands. The rest are a collection of airband, marine, FEMA, search and rescue, National Guard, US Air Force, etc. Most of these frequencies are not legal for the general public to use. An FCC amateur radio license permits operation on the two ham radio frequencies listed but nothing else. The 4Patriots has a similar list, leaving out the ham radio frequencies and calling the list “other emergency radio frequencies.” The Save Net Radio website also has a poorly thought-out frequency list. But they compound their errors with this statement:
It’s important to note that these frequencies aren’t just for professional rescuers and emergency workers; they can also be used by ordinary citizens who are equipped with the appropriate radio equipment.
This is incorrect and potentially dangerous.
Some Specific Frequencies
These emergency frequencies have three main uses: situational awareness (listening to learn what is happening in your environment), distress calls (calling out to anyone for help), and coordination with friends (communicating with friends and associates about supplies, health and welfare, transportation, weather, etc.)
We must consider our radio’s capabilities, specifically the frequency range (for transmit and receive, which may differ) and modulation type (AM, FM, SSB, etc.). The typical low-cost VHF/UHF radio that is so common (Baofeng UV-5R or similar) has a frequency range of 136 to 174 MHz (VHF) and 400 to 520 MHz (UHF). Many of these radios are shipped with their transmit frequency limited to the amateur (ham) radio bands: 144 to 148 MHz and 420 to 450 MHz. However, there may be a method to enable (or unlock) the entire frequency range for transmitting. Check the specifications of your radio model. These radios are almost always FM only, so no AM or SSB. Some radios can receive AM in the aircraft band but won’t transmit AM.
Listening to radio activity around you can be very helpful in understanding situational awareness. A good example is listening to your local fire or law enforcement channels. You can hear some of these frequencies using a low-cost VHF/UHF radio but a scanner that receives digital signals will be a lot more useful.
Let’s examine some of the frequencies in the Stryker list. I will skip the frequencies outside the typical VHF and UHF tuning ranges listed above, as your radio most likely won’t be able to tune them.
138.225 MHz: Primary FEMA channel for disaster relief operations.
This frequency is in the federal VHF band, but I could not confirm a specific usage.
To transmit on this frequency, you need federal authorization.
146.52 MHz: Ham radio frequency for non-repeater communications on the two-meter band.
This is the 2m FM calling frequency, which is generally lightly used. You may hear interesting traffic on this frequency but need a ham radio license to transmit on it.
151.625 MHz: Utilized by mobile businesses such as circuses, exhibitions, trade shows, and sports teams. Other channels in use are 154.57 and 154.60 MHz.
This is an itinerant business band frequency known as the Red Dot channel. The other two frequencies listed are MURS Channels 4 and 5. They may be useful to program in.
154.28 MHz: Local fire department emergency communication channel. Additional frequencies include 154.265 and 154.295 MHz.
These are Fire Mutual Aid channels (VFIRE21, VFIRE22, VFIRE23) set aside for when multiple fire districts need to communicate. Typically, each district has their own radio frequencies and only uses these when a large incident occurs with multiple agencies responding. An FCC license for these specific frequencies is required to transmit on them.
155.160 MHz: Local and state agency channel for search and rescue operations.
This is the most common VHF frequency for Search and Rescue. To transmit on it, you need an FCC license for this specific frequency.
155.475 MHz: Local and state police emergency communication channel.
This is a Law Enforcement Mutual Aid channel (VLAW31) set aside for when multiple law enforcement agencies need to communicate. An FCC license for this frequency is required to transmit on it.
156.75 MHz: International maritime weather alerts channel.
This is marine channel 15, receive only, reserved for listening to emergency locator beacons. This is not a normal communication channel and is probably not useful in an emergency.
156.80 MHz: International maritime distress, calling, and safety channel.
This is marine channel 16, the calling and distress channel, which may be useful in coastal areas, lakes, and waterways that have significant marine radio activity. This frequency is for marine / boating use using a certified VHF marine transceiver.
162.40 MHz to 162.55 MHz: Series of channels used for NOAA weather broadcasts and bulletins. Also 163.275 MHz.
These well-known weather broadcast stations cover a large portion of the US and are very useful to have programmed in your radio. Do not transmit on these frequencies.
163.4875 MHz: Nationwide emergency channel for the National Guard.
163.5125 MHz: National disaster preparedness frequency for the armed forces.
164.50 MHz: National communication channel for the Department of Housing and Urban Development.
These are federal frequencies requiring federal authorization to transmit on them.
168.55 MHz: Federal civilian agency channel for emergencies and disasters.
This frequency is assigned exclusively to smoke jumpers working on wildfire suppression.
Do not transmit on this frequency.
409.20 MHz: National communication channel for the Interstate Commerce Commission.
409.625 MHz: National communication channel for the Department of State.
These are federal frequencies requiring federal authorization to transmit on them.
462.675 MHz: General Mobile Radio Service channel for emergency communication and traveler assistance.
This is Channel 20 on GMRS and FRS radios. This frequency is probably useful, but it is subject to the GMRS and FRS rules.
Some of these frequencies may be useful to monitor in an emergency (situational awareness), but very few are available for distress calling or communicating with friends.
RadioMaster Reports Frequency List
This list originated on the Radiomaster Reports website and has spread around the web in various forms (see below). It is one of the better prepper frequency lists, but it still has some issues.
The FRS and GMRS frequencies are useful to have available. The PMR UHF frequency (446.03125 MHz) listed is actually in the 70 cm ham band in the US and is a non-standard frequency, so it should not be used at all in the US. (PMR is a European standard.) The CB frequencies listed are not available on your typical low-cost VHF/UHF handheld but are useful if you have a CB radio. The so-called CB Freeband frequencies are never legal for use and your standard CB won’t tune them.
The low-band VHF frequency of 33.4 MHz will also not work with your typical handheld radio. The FCC license database shows many businesses are licensed to operate on this frequency, including many fast food restaurants. I suppose if you want to order a hamburger in an emergency, it might work.
If you have the appropriate amateur radio license, the Ham VHF and HF frequencies listed are usable in the US. On the 2-meter band, 146.52 MHz is indeed the nationwide calling frequency and was discussed earlier. However, the frequencies of 146.42 and 146.55 MHz do not always conform to local band plans, depending on the area of the country you are in. So you may or may not find activity there. The Search and Rescue frequency (155.16 MHz) was discussed earlier. The two marine frequencies listed do not require a license but should only be used for boating and similar communications.
Summary
We could continue to examine the specifics of all these frequencies and discuss their equipment requirements, licensing requirements, and proper usage. However, the main message is that these frequency lists are just a collection of random stuff compiled and propagated around the web. None of them are well-considered and most will likely not do you much good in an emergency. And they might lead uninformed citizens into using a frequency that can get them into a heap of trouble.
I have been looking for a list to recommend but have not found one. Let me know if you come across one that is truly useful.
That’s what I found. Let me know what you think.
73 Bob K0NR
References
National Field Operations Guide (NFOG)
https://www.cisa.gov/safecom/field-operations-guides
NTIA Redbook
https://www.ntia.doc.gov/publications/redbook-manual
RadioMaster Reports Frequency List
https://radiofreeq.wordpress.com/wp-content/uploads/2013/06/shtf_survivalist_radio_frequency_list.pdf
The post Erroneous Prepper Frequency Lists appeared first on The KØNR Radio Site.
The SARC Communicator – January-February 2025
New desktop publishing software opens up even more possibilities for the SARC Communicator, the digital periodical of Surrey Amateur Radio Communications. This issue is now available for viewing or download. Another new feature is a smaller version, best suited for mobile devices, available here for viewing or download. The advantage of the larger version being higher resolution graphics and photos.
The best new feature, in my opinion, is the ability to provide you with a compete Table of Contents [below]. This should enable better accessibility from search engines.
You will find some great articles in this issue, along with our regular columnists.
Now read in over 165 countries, we bring you 120+ pages of Amateur Radio content from the Southwest corner of Canada and elsewhere. With less fluff and ads than other Amateur Radio publications, you will find Amateur Radio related articles, projects, profiles, news, tips and how-to's for all levels of the hobby.
Download the January - February Communicator in
LARGE or SMALL format, or read it on-line like a magazine
Previous Communicator issues:
Search for past Communicator issues
and a full searchable index is HERE.
As always, thank you to our contributors, and your feedback is always welcome.
The deadline for the next edition is February 15th.
If you have news or events from your club or photos, stories, projects or other items of interest from BC or elsewhere, please contact us at [email protected]
73,
John VE7TI
'The Communicator' Editor
The Table of Contents for the January-February 2025 Communicator issue:
- The Rest of the Story: Charles Wheatstone 4
- News You Can’t Lose: Field Day results are in 12
- Page13—News You Can Lose 13
- Radio Ramblings: Reflections 15
- Does the Ghost of Salvador Dali Haunt ChatGPT? 26
- Tech: A transceiver on your Android phone 27
- Xiegu G90 Review 28
- Another Tape Measure Antenna 31
- POTA is Calling - Will you answer? 32
- A Different Kind of Foxhunt 34
- USA Radio Orienteering Championship 35
- Mastering iCOM HF: A deep dive into filtering capabilities 37
- Schooling ChatGPT on Antenna Misconceptions 42
- LIDS: The Less Involved Data Society 43
- Experimental Maritime Mobile on 630m 44
- From the ATV Journal 48
- B.C. QSO Party 50
- A Light Dipole 52
- An Easy Field Strength Meter 53
- AMSAT - OSCAR 7 55
- Dutch Amateur Radio Operators Detect Signals From Voyager 1 56
- Update on the Local High Altitude Balloon Project 57
- They Don’t Make ‘em Like They Used To… 58
- LingoSat ISS Deployment 59
- Canadian Amateur Radio Hall of Fame Appointments 2024 60
- The Santa Barbara 1925 Earthquake 62
- Ham Radio Outside the Box: Antenna height matters 65
- What Did Beethoven Do For Ham Radio? 68
- VE9KK - The World of CW: I am at peace with the RFI gods 69
- K0NR - 2 Meters: Handie-Talkie or Walkie-Talkie? 71
- Which Modes Have You Operated? 73
- KB6NU’s Ham Radio: Hurricane Helene 74
- Pico-based SDR runs stand-alone 75
- Foundations of Amateur Radio: The venerable QSL bureau 76
- No-ham Recipe: Oatmeal brown bread 79
- Back to Basics: Codes & encryption 80
- Profiles of SARC Members: Jeanne Wilson VA7QD 88
- CQ WW DX Contest [CW] 92
- ARRL 10m Contest 94
- RAC Winter Contest 96
- SARC News… 97
- SEPAR Report 103
- Ham Leftovers... 107
- QRT: Blog vs PDF? 108
Top Five K0NR Blog Posts for 2024
Closing out 2024, here are the top five blog posts at k0nr.com during the year. Some people may see this as a lazy way of creating one more blog post for the year without much effort, and they would be right. These posts are the top five viewed during the year but may have been written earlier.
Top Five Blog Posts
Leading the list is this blog post…a perennial favorite that seems to make the top five each year. This particular article is tuned for Colorado but also provides a link to an article covering the topic for the USA.
In second place, this is another popular article that introduces 2-meter SSB operating.
New to the list this year is an article I wrote in the latter half of 2023. It talks about the station I’ve been using for both SOTA and POTA activations, built around the Icom IC-705.
This post, which comes in fourth place on the list, explains how the FCC rules prevent having one radio that does everything.
In fifth place is this article describing the RH770 antenna for use with dual-band 2m/70cm handheld radios. This is a high-performing yet inexpensive antenna that should be in your toolkit.
Editors Choice
Just for good measure, I am including one more post that I think is notable. I started wondering when the name “Handie-Talkie” was first used to describe a handheld radio. This led me down a path that taught me about radios used in World War II. Interesting stuff.
Merry Christmas and Happy New Year!
73 Bob K0NR
The post Top Five K0NR Blog Posts for 2024 appeared first on The KØNR Radio Site.
HamCon Colorado 2025
Mark your calendars…
Flyer in PDF format
HamCon Colorado website
The post HamCon Colorado 2025 appeared first on The KØNR Radio Site.
















