Amateur radio: details of my first time working HF

Okay, now for the more extended story concerning the beginning of my true amateur radio operating “career”.

My goal was to at least listen in on the ARRL’s SSB Sweepstakes Contest on November 20th.  I had built a 10-foot circumference magnetic transmitting loop detailed here. I had already decided that without putting the loop through more rigorous testing, I would turn my Yaesu FT-450D all the way down to 5 watts and work in the QRP category. I’ve read people saying that running QRP and doing a contest are the two of the worst things a beginner can do. Furthermore, the Sweepstakes has a more involved information exchange than most contests. But, I was going into this with eyes open, and especially with ears open.

Unfortunately, after testing the 10-foot loop, I found out that with my high-voltage tuning capacitor, the antenna was resonant from around 9250 to 20850 kHz. A nice range, but would only get me SSB access on 17 and 20 meters, and 17 doesn’t count for this contest. (60, 30, 17, and 12 meters are considered off-limits for contests). I really wanted to have options on two bands with the antenna, so I used this on-line calculator to figure out something optimized for both the 20- and 40-meter bands. This ended up being a 15-foot circumference loop made out of 1/4″ copper coil pipe, which is much easier to bend than the 1/2″ pipe I used for the 10-foot loop.

I didn’t buy the 1/4″ copper coil until Friday after work, and didn’t make much progress that night. Finally, Saturday evening I had a chance to get this all together. Once I put together this loop, I ran it through my miniVNA Pro, getting it to resonate from 6700 to 15000 kHz. That very nicely covers 20 and 40 meters, with not a lot of extra at the high and low end. The problem is that when testing this indoors I was having trouble getting an SWR better than 3:1 using what is supposed to be the nominal coupling loop, 1/5th of the size of the main loop. I went to a loop 1/3rd the size, and that got the SWR below 1.5:1.

However, once I put the antenna up and tested the SWR, I was back to 3:1 again. It was already 2am, and I contemplated quitting at that point. But, I realized that I should go back to the standard 1/5th-size coupling loop and that got the SWR back to 1.05:1 at resonance. With that in place, I decided that since I was up, I should go ahead and see if I could take advantage of the overnight 40-meter propagation.

One problem with the 40-meter band versus the 20-meter band is that the SWR 3:1 bandwidth is way smaller than for the 40-meter band. I.e., one setting only covers a bandwidth of 24 kHz, as compared to the 125 kHz legal range as a General class operator. So, here’s what I did. I set up the miniVNA Pro and laptop so I could see the display through the window from where I had the antenna. Using a ladder and one of those helping hand grabbers, I could rotate the variable capacitor knob (10 feet up), step down and look in the window to see if I had the resonant frequency correct, and repeat the process until I was centered where I wanted. Reception is still good enough off-center, so I could use that to decide if I wanted to shift to another frequency for transmitting.

I started out tuned to 7215 khz, noticing several shortwave stations in that vicinity, but also some contesters. I listened to someone from Michigan calling CQ for a while on 7191 kHz and I finally got up the nerve to respond at 1026UT. He was having some trouble hearing me, but we eventually made the QSO, my first on HF! One thing to keep in mind is that my loop is optimized for 20 meters, and the on-line calculator estimated around 15% efficiency. Thus, I was radiating less than 1 watt! (I’m using some good low-loss coax, which I measured with the miniVNA Pro as having only 0.2dB loss on the 40-meter band, or just 5%.)

I continued hunting around, hearing almost exclusively stations east of the Mississippi and was mostly unsuccessful contacting them. My second QSO was also Michigan at 1130UT, also on 7191 kHz. I worked Kansas a little while later, and while it took a full minute for the QSO, I worked Maryland on 7228.7 kHz at 1238UT! Two thousand miles on SSB on 1 watt!

I tried for another hour to get another QSO, but kept not being heard. So I decided to take a break and came back on 20 meters at 1540UT, well after local sunrise. On 20 meters, the estimated antenna efficiency is over 60%. However, I had a long stretch of not being heard, probably as much to do with the airwaves being much busier during the day.

Finally, I made my first-ever 20 meter QSO at 1730UT to Texas, then had two more contacts before the end of the hour. The second half of the 18UT hour also gave me 3 more QSOs, including Maryland again! At 1908UT, I finally made a QSO with someone that I had just missed earlier, my 11th and final contact. I took an hour-long break, but by then the background noise level had shot up nearly 2 S-meter units up to S7, and there was possibly some weather moving in so I quit.

Lessons learned:

  • I fumbled my exchange information a few times even though I had the non-changing stuff written down in front of me. I just need more practice.
  • I’m really appreciative of the high-power operators that were willing to dig me out of the static for the QSO. That’s actually one advantage to working a contest if you are running low power and are unsure of your equipment; they need every QSO they can get if they want to be competitive.
  • For this reason, it was not effective for me to respond to any CQ call that was reading less than about S9 and even that level wasn’t enough sometimes. I was presumably 3-4 S-units weaker than the person I was hearing, so that seems to be about right.
  • I’m a bit less impressed now by CW operators talking about making long-range contacts running 1 watt.
  • I need to run an antenna switcher in reverse so I can switch between my transceiver and the miniVNA Pro to make tuning easier.
  • I need to motorize the tuning capacitor to make tuning even easier.
  • This is pretty fun!

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