Saturday, September 06, 2008

One Missed Contest; Another Upcoming

I did not actually miss the Ohio QSO Party (OQP). I had put it on my calendar at least a month out, and the reminders popped up on my computer screen at the appropriate times. I just decided to sit it out this year. I'm in an apartment and currently my antenna is indoors. I normally try to keep my RF power set at lower levels, which have been fine so far for PSK31 and other digital modes. I was actually quite surprised when I ran my numbers through the RF Safety Calculator on the University of Texas website. The highest power setting that I think that I have ever used for PSK31 is 40 watts. However, PSK31 is a 100% duty cycle mode (there are always tones being emitted), so 40 watts is also the average power. The calculator asks for average power, so I use 40 watts. It also asks for the frequency of operation. I used 7, 10.1 and 14 MHz, and it asks for the gain of the antenna, and suggests 2.2 dB for a dipole. I have a Buddipole, which is a form of dipole, so I use 2.2 dB. On the 40 meter digital segment, a person in the uncontrolled environment has to be 2.04 feet from my antenna. On 30 meters, that number increases to 2.92 feet, and on 20 meter digital, one has to be 4.03 feet from my antenna. Keep in mind that the calculator asks for average power at the antenna. So I could have subtracted off losses in the coax: I'm using a combination of RG-58 and RG-213. I think that it is also implied that antenna inefficiencies could be weighed in, too. Obviously, antennas that are not resonant, or use things such as loading coils, will take some of the RF and convert it to heat in the coax or the antenna itself. That RF won't be radiating and potentially exposing someone. The point is that my neighbors are easily at a safe distance away. Things look even better when you talk about SSB, which is what I would have used in the OQP. In the OQP, I probably would have gradually worked the RF setting up to the full 100 watts that the TS-2000X is capable of, but SSB is not a 100% duty cycle mode. The characteristics of speech are such that the average power of SSB is about 20% of the peak power. Therefore, on the RF Safety Calculator, I would have put in 20 watts for average power, even though my radio is set at 100 watts. The 20% number assumes that a speech processor is turned off and you aren't using heavy equalization.

To make a long story short, I sat out the OQP because I wanted to be able to set up my antenna outdoors (not because of RF safety, which appears to be under control, but because 100 watts will create havoc in the shack), and I hadn't made arrangements to do that yet.

I will have my big chance to enter a contest in a matter of weeks. For a 48-hour period starting on October 25 (UTC) and running through October 26, the CQ Worldwide DX SSB Contest will be going on. Last year, I made six DX contacts during the contest, but I never officially entered. In other words, I did not submit a log. This year I will probably enter in the Single Operator Low Power category. I did notice the other day, that the logs from 2007 are available for viewing on the web. I checked the six logs for the stations that I worked: VP5T, ZY7C, ZF2AH, 6F75A, VP9I, and V26B. I appeared in four of the six logs. For whatever reason, I was not in the ZY7C log nor the 6F75A log. The operators probably misread my call. 6F75A is Mexico (yes, last year's CQWW DX SSB contest was my first real exposure to unusual callsigns). I've got Mexico (XE3RR on PSK31) confirmed on Logbook of the World. ZY7C is Brazil. It would've been nice to ask for a confirmation for that, but there is no point, since I'm not in their log. Assuming 15 meters opens up again this year like last year, Brazil and other DX should not be too hard to obtain, but 20 meters should work, too.

73

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