Results from the RAC 2021 Survey
In this brief article, I focus on how much transmit power is typically used on the HF and microwave bands. Survey respondents were asked about what they consider “typical” usage although these settings can certainly be different at any given operation. The results do give the reader a picture of how amplifiers are used on these two broad segments of band allocations by Canadian ham operators.
In Figure 1 (click for larger image), the maximum power used to transmit on 160-6 meters is displayed in a pie chart. Although many may not agree that 10 watts is QRP power, we are using that convention here. About three-fourths of the survey respondents say they use between 10 and 150 watts in a typical transmission. This is a wide gap in RF power. However, it is a range that places operators between QRP and what many of today’s HF transceivers will output. Some 17 percent use over 150 watts, perhaps up to their license limit. Only 7 percent report that they use QRP levels at less than 10 watts. These responses are not contingent on the mode of transmission.
Turning to the VHF and UHF bands, Figure 2 summarizes the typical power used in Canada. A similar pattern occurs as in HF and six-meter operation. Just under three-fourths (71%) use between 10-150 watts on a regular basis. A small slice, some 2 percent, report over 150 watts. About one-fourth (27%) say that less than 10 watts is what they typically use in these bands.
In both HF and the VHF/UHF frequency bands, only a small proportion say they use amplifiers to reach over the 150-watt RF power mark. There is a small but notable share using what we’ve termed QRP levels in HF (7%). A decidedly larger share use above QRP levels in VHF or UHF bands (27%). For many hams, this is very understandable, given the most popular band of 2 Meters (92%). But operations on HF using a 10-watt definition of QRP are much smaller.
The power utilized in the microwave bands reflects a very different picture. Figure 3 displays two box plots to illustrate. As shown in previous articles on this blog, microwave band usage is a niche activity within Canadian ham radio. Fewer than 10 percent report any activity but these spent quite a bit of time on these frequencies. Likewise, the boxplot in the left panel of Figure 3 illustrates the small number of microwave aficionados who use high power. (This is power in watts without consideration of antenna gain.)
In the right panel, I’ve reproduced the left-hand panel’s data in watts into a logged form to allow readers to more closely see the lower power portion of the distribution. The log of the power in watts places less emphasis in the smaller frequencies at the extreme power levels. The average power usage is 40 watts with a majority under 100 watts of power. This is not the power level emitted from the antenna with is buoyed by the relative gain of the antenna.
I examined these transmitter power reports by province, age group and license class. There was not much meaningful variation in those data apart from the differences in reported activities on microwave bands. In part, this is the limitation I mentioned of the small number of extreme values in the upper power range. The specialization of using high power in the microwave frequencies is a small number of Canadian hams, at least in this survey. It would take a new sampling design to “over sample” hams who are microwave users to get a more reliable estimate of the higher power ranges in use.
In summary, power output in Canadian amateur radio operations tends to reflect the output of the transceiver on HF bands. There is a wide variation in the category but this is a reasonable conclusion. QRP use is a bit smaller than I expected, given the popularity of portable operations (37%). But this reminds us that not all portable operations use low power. There is innovation in a small group of microwave operators. They use a significant amount of power. A later article will examine reported gain in antennas used in this band. As the microwave bands become more routinized in the hobby, these pioneering leaders will have laid a path for others to follow.