Many thanks to Brian (K3ES) who shares the following guest post:
Field Report: Winter Field Day with a New Antenna
Winter Field Day (WFD) 2022 found me operating indoors, despite my best intentions to get out in the field. I was recovering from a bad cold, and did not want to risk having complications arise from sitting out in the cold and damp. So for WFD 2023, outdoor time with my radio was a must. I wanted to operate a 1-Oscar station, and to do that I had to set up more than 500 feet from my home QTH. So a site next to the pond in our back field, about 800 feet from the house, became my WFD shack.
I started planning and collecting kit for the operation in mid-January, with the long term forecast hinting at near-freezing temperatures with the potential for rain or snow. Let me introduce you to my WFD station.
Shelter
A shelter was needed to keep out rain and snow, and to provide a barrier against the winds whipping across the adjacent field. A few poles lashed together, and steadied by stakes, provided the frame to support the shelter. With a poly tarp secured to this frame, the resulting a-frame shelter, while not completely enclosed, did provide effective weather protection for both operator and equipment. There was about 3 inches of snow on the ground when I set up the shelter, and I was able to pile some of it along the bottom edge of the tarp to keep the wind from getting under it.
Antenna
I know that when setting up a station, the antenna is not generally the first thought, but I had recently finished building a homebrew 9:1 random wire antenna with a 144 ft radiating wire, and I wanted to test it out. There are better ways to put a new antenna on the air, but the opportunity was a good one. Besides, I had backup antennas that could be quickly substituted if the need arose. In the event, things worked well, and the antenna proved agile and capable on all activated bands. I particularly wanted to see if it would tune on the 160m band. More on that later.
Radio
The goal of trying the antenna on 160m left me with only one choice for a radio. I would use the Lab599 TX-500 Discovery, because it is the only transceiver among my field rigs that is capable of operating on the 160m band. Since a tuner is required, I paired it with an LDG Z-11Pro II, a wide-range autotuner. I also included a Monitor Sensors Power and SWR Meter in the feed line to help assure that I was legitimately running less than 5 watts to qualify for the QRP power multiplier.
Power
Expecting it to be more than sufficient, I planned to power the radio, tuner, and power meter with a 12 amp-hour LiFePO4 battery. I brought along a 6 amp-hour LiFePO4 battery as a spare, just in case. I also wanted to protect against battery failure due to cold operating temparatures, so I placed them in a small cooler and dropped in a couple of hand warmer packs for good measure. The battery system met the requirements for the Alternative Power bonus, and was completely independent of commercial power for the duration of the operation.
Shack Equipment
To complete my shack away from home, I brought a few other pieces of equipment for operation, and for creature comforts. I sat in a folding chair to stay off the ground. A piece of scrap plywood provided a luxurious operating desk. A 5-gallon bucket that I had used to transport materials and equipment to the field location did extra duty as a table to support the Z-11Pro II and the Power and SWR Meter. While I normally do field logging strictly on paper, I decided to try electronic logging this time with HAMRS software running on a Samsung tablet. I did have paper and pencil close at hand as a backup, if needed. Completing the station were a BaMaTech TP-III CW paddle, and a set of generic earbuds. To continue operation after sunset, I had a battery operated head lamp provided illumination in the shack and on the walk back to the house. Final creature comforts included an old moving blanket for extra insulation, and a thermos full of hot tea for operator revival, both of which proved quite beneficial.
Equipment List
- Transceiver: Lab599 TX-500 Discovery
- Antenna: Homebrew 9:1 unun with 144 ft (43.9m) radiator and three 17 ft (5.2m) counterpoise wires
- Tuner: LDG Z-11Pro II
- Power Meter: Monitor Sensors Power and SWR Meter
- Feedline and Jumpers: RG316 coax with male BNC end connectors
- Key: BaMaTech TP-III
- Earphones: generic ear buds with 3.5mm mono male to 3.5mm stereo female adapter
- Power: Bioenno 12V LiFePO4 batteries (one each 12 Ah and 6 Ah)
- Battery Protection: Igloo Little Playmate cooler and HotHands air activated warmers
- Arborist Throw Line: 8.8 ounce Petzel throw bag with Marlow Excel 2mm line
- Shelter: 15 ft x 19 ft poly tarp stretched over a lashed frame of poles
- Cordage: 3/16 (5mm) inch polypropylene rope and 550 cord
- Working surface: 18 in (45 cm) x 36 in (90 cm) scrap of 5/32 in (4mm) plywood
- Logging: HAMRS on a Samsung tablet, backed up by a Rite in the Rain No 946 tablet and a Pentel Twist-Erase 0.9 pencil
- Lighting: Battery operated head lamp
- Other: Full size folding camp chair, a 5 gallon plastic bucket, and a plastic utility sled
WFD Operation
I focused my operation on CW mode at QRP power levels. Knowing that my schedule only permitted me to operate on Saturday afternoon and evening, I decided to start on 10m, then to work my way down the bands as time marched toward sunset. I wanted at least one contact on each band, but planned to move successively to lower bands as contacts became difficult to find. I had the option to move to SSB to improve my multiplier, but honestly had so much fun with CW that I stayed with that mode throughout. Most of my contacts came from search and pounce operation, but I did spend some time running a frequency when band conditions left space for success at QRP power levels. One final goal for the day was to make a contact on 160m to prove that capability with the new antenna. More on that later.
WFD Results
Altogether I was able to log 44 WFD contacts on 5 bands in 4-1/2 hours of operating time. Table 1 shows contacts by band, and Figure 12 provides the associated contact map.
| Band | Number of QSOs |
| 10m | 2 |
| 15m | 10 |
| 20m | 14 |
| 40m | 14 |
| 80m | 5 |
Table 1: A summary of QSOs by Band from Winter Field Day operations.
A Contact on 160m
As sunset came and went, I knew that the time was right to try the 160m band. I found what I hoped was an an open frequency on the band, engaged the Tone function on the TX-500, and punched the tune button on the antenna tuner. The Z-11Pro II clicked and whirred with its SWR status LEDs reflecting progress, then it ultimately settled on a match yielding 1.4:1 SWR. Awesome! Then came the problem.
The 160m band was packed wall-to-wall with CW signals, and none that I could find were calling CQ WFD. The CQ 160m CW contest was going full swing, and if there was a WFD station operating, it would be like finding a needle in a haystack. So, with temperatures falling, and hot tea failing to keep the chill off, I settled for the next best thing. I found a strong station calling CQ Test for the 160m contest and sent my call. The VE3 operator came back with “599 ON”, I sent back “TU 599 PA”, and called it good.
My antenna design worked. I was happy with the results of my afternoon and evening on the air. So I packed up my station and headed back toward central heating.
An Unexpected Bonus
I do have to confess that I lost focus on WFD for about 10 minutes in the middle of the afternoon. While tuning across the 20m band, I heard a VK station calling CQ. Knowing that there had to be magnificent propagation, but not really expecting to be heard, I sent back my callsign… I got an immediate response containing part of my callsign. It took a dozen or more repeats before my full call came back to me (it turns out that the single QRP dit signifying the Echo portion of my callsign can easily be lost in the noise, but we managed to work through it). I received a 449 signal report and sent back 559. With thanks and 73 from both ends, I had a completed QSO in my log, though not for WFD. Oh, and while transmitting during the exchange, I happened to glance at the Monitor Sensors Power and SWR Meter. It read 3.67 watts!
After returning to the house, I sent a quick e-mail to VK2GR thanking him for the QSO and expressing my gratitude for his patience. I also gave him details for my station, including the power level. The next morning I received Allan’s very gracious reply. He was running 400 watts to a 4-element Yagi (he definitely was doing the heavy lifting for the QSO). But there was more. He had his antenna directed long-path. With propagation via long-path, 3.67 watts carried my signal more than 15,000 miles. Incredible!
Final Analysis
I had a few lessons worth sharing from my Winter Field Day experience. The tarp shelter was probably my greatest vulnerability. It worked, but higher winds could have caused real problems. There were some concerning wind gusts while I was erecting the shelter, but the winds calmed before WFD started, and the shelter survived. The snow I piled on the ends of the tarp did work to keep the wind from getting under it, which likely kept it from being blown over before WFD even started.
Speaking of snow, having a few inches of it on the ground was a real help. I ran a heavier than normal station (I like to keep my gear in a small pack for POTA activations) including extra gear for antenna tuning and station monitoring, as well as the shelter and furniture. As I was assembling gear for the effort, I found a sled that proved perfect for transporting needed materials across the ½ mile of broken, snowy ground between house and station. Three trips out and two trips back proved sufficient for moving all of the equipment and supplies.
I tried my hand at direct logging to HAMRS on my tablet. I have been reluctant to take this step. My real fear was that error correction during a QSO would be difficult. It was. While I touch-type competently, I make more mistakes and take longer to correct them when using a touch screen. Don’t get me wrong, it worked, and my log is complete, but I’m not ready to give up my pencil and paper for field logging. Just call me a dinosaur.
Finally, I have a winner with the new antenna. I am really pleased that it tuned well on all bands, including 160m. I am blown away to have completed a contact with Allan in Australia. I do need to make structural repair to the feed-point end, but the mechanical damage that occurred had no impact on operation, and the fix should simple. I hope to provide details of the antenna: objectives, design, construction, and testing in a future QRPer Field Report. As a final note, I have officially christened the antenna: I give you the VK160.
Best 73 de Brian – K3ES
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