DX for Techs
The following DX article was written by Bob Loving, K9JU, of the Smoky Mountain Amateur Radio Club (SMARC), and ETDXA. It was submitted to ETDXA by Bob for publication on our website.
​
It is intended for the Technician Class.
The World of DX – 2024 May
Hello again fellow SMARC members. Welcome back to the fascinating world of DX.
In the very first World of DX column, I explained some of the facets and terms used in DX. The second column outlined some ways you can get started in this popular facet of the hobby. The third/previous column showed some tips on working DX stations that are not in a contest. The column for this issue of the newsletter will implore the Technician Class Amateur Radio operators (“Techs”) to use your HF privileges on the 10M band.
Firstly, just which overall High Frequency (HF, 3- to 30-MHz) privileges do Techs have? You are limited and it is a good incentive to upgrade to at least the General Class license to expand your HF bands and modes of usage. Here is a breakdown from the ARRL “US Amateur Radio Bands.” You can download the chart from http://www.arrl.org/graphical-frequency-allocations. Here is a sample of the chart:
​
​
​
​
OK, it is very blurry but the PDF image is sharp and you can print a copy to keep nearby your operating position at your home and mobile stations. For your edification, here are summaries of the Technician Class HF privileges; in all cases, the maximum output power at the antenna connector of the transceiver (or an external amplifier) is 200-Watts:
1) On the 80M band, you are limited to Morse Code (“CW“) from 3.525 to 3.600 MHz. Note that you do not have any digital or phone privileges on this band.
2) On the 40M band, you are limited to CW from 7.025 to 7.125 MHz. Again, note that you do not have any digital or phone privileges on this band.
3) On the 15M band, you are limited to CW from 21.025 to 21.200 MHz. Again, note that you do not have any digital or phone privileges on this band.
4) Before I continue to the 10M band, I must emphasize that the above three bands are CW only and Technicians have absolutely no privileges on the 160M, 30M, 20M, 17M and 12M bands.
Now to the meat of the subject, Technician Class operator privileges on the 10M band. We will assume that you are using a modern transceiver with a stable and accurate frequency synthesizer that uses a digital display.
1) The frequency operating range for Techs is 28.000 to 28.500 MHz. The band is quite a bit wider than this segment, extending all the way to 29.700 MHz.
2) As with the 80M, 40M and 15M bands, Techs may transmit CW (Morse Code) in the frequency segment from 28.000 to 28.500 MHz.
3) With regards to data transmissions on HF, Techs may use 28.000 to 28.300 MHz. However, most 10M CW operation by the other classes, as well as Techs, is generally from 28.000 to 28.070 MHz. With this in mind, please do not call CQ or carry on a conversation with your buddy with PSK31, RTTY, FT8, etc, below 28.070 MHz. There are various “watering holes” where one will find the majority of digital mode operations; the watering hole for the very popular WSJT-X mode FT8 is 28.074 MHz.
4) The voice mode for Techs is only SSB (Single Side Band) between 28.300 and 28.500 MHz. The standard sideband to use on the HF bands from 20M to 10M is Upper Side Band (USB). Keep in mind that if you put your “suppressed carrier” at 28.500 MHz, your sidebands will extend to approximately 28.503 MHz, putting your transmission “out of band” for your Tech privileges. The cooperate program between the FCC and the ARRL, Volunteer Monitors, may send a notice to you of such transmissions. Therefore, ensure the digital display of your transceiver does not read higher than 28.497 MHz when operating SSB.
5) FM operation on the 10M band is not allowed for Techs, period.
Now that I’ve lectured you on the HF privileges, albeit limited, afforded to the Tech license, why I am doing so? I wanted to emphasize the 10M band as being the only HF band in which you have data and phone privileges. Again, why? As a parent, the answer could be either “because” or “because I said so”! The real reason is the “Solar Cycle” (“SC”) and in particular the present cycle, number 25. Let me explain.
Solar Cycles have ups and downs of sunspot activity of the sun. A solar cycle is measured by the amount of sunspot activity. The average length from the bottom (few or no sunspots) to the top (many sunspots) and back to the bottom (few or no sunspots) is approximately 11 years. The length of a solar cycle can vary from a low of 9 years to a high of almost 14 years. The previous cycle, SC24, was 11.0 years long and ended in 2019 December when SC25 began.
From the previous paragraph, SC25 started 2019 December; we are just over 4 years into the cycle. Solar cycles tend to rise more quickly than they decay. If predictions are correct then the peak of SC25 is nigh and should occur sometime between now and early 2025. For more information on solar cycles please refer to Wikipedia, https://en.wikipedia.org/wiki/Solar_cycle.
At this point, you may be saying to yourself, “so what!” The “so what” is solar activity has been high for many months in a row and the 10M band is alive with DX activity. Many DXpeditions are on the air and others will come on the air in the near future.
It should be relatively easy for you to work sufficient numbers of stateside stations to earn the Worked All Sates (“WAS”) award. With DX conditions ranging from good to fantastic, the coveted DX Century Club (“DXCC”) award is well within reach. Activity galore from all over the world should allow you to
work and confirm contact with 100 countries/entities necessary for the entry level of the DXCC program. Both the WAS and DXCC programs are administered by the ARRL, Newington, CT.
From experience, the 10M band will open soon after sunrise and propagation is predominantly eastward toward Europe. As the day progresses, propagation swings westward with Asian stations tending to appear mid to late afternoon. Towards evening, look for stations out of the southPacific Ocean like Australia, New Zealand and the numerous Polynesian islands.
If you become disappointed you can’t contact someone on the first call, here is a note of encouragement. By the way, it happens to all of us regardless of the years of chasing DX (or stateside contacts). If there are a number of stations calling that station, their signals are probably stronger than your signal at the DX location; it’s kind of a “no duh. Your antenna may not be “up to snuff” to efficiently transmit a loud signal. With high solar activity, you could hear signals on 10M with a paperclip stuck in the antenna connector of your radio but it won’t radiate very well. You get the idea.
Speaking of antennas, one of the members of SMARC has said on many occasions, “nothing beats a simple, centerfed half wavelength dipole.” The 10M band is a good example of bands to experiment with various antennas because a half wavelength dipole is roughly 16’ long. Hung between two supports about 16’ above ground and the antenna will operate quite well in the directions perpendicular to the wire. The feedline should be low loss such as RG-213/U. Although the antenna, constructed and installed as described, will be close to 75 Ohms at the feed point, that represents a 1.5:1 SWR and is easiily handled by modern transceivers.
Another possibility for a rather cheap feedline is RG-6 that was used used by cable companies. It has a 75 Ohm characteristic impedance to match the antenna and the loss isn’t too far from RG-213/U. Plus the RG-6 is lighter and, most likely, much cheaper. There is always the chance you might find a good length for virtually no cost.
Until next time, “73 ES GUD DX.”
Bob K9JU
Please email any comments or suggestions to "k9ju@arrl.net".
Disclaimer: I have no pecuniary interest in Heil Sound, Ltd.
