We had the usual great time at Manyane this past weekend where we hooked up with our friends Tony and Pat. They have a great camping trailer and we enjoyed a number of excellent meals and a good social time there. The weather is still quite decent and mild so no problem staying warm.
From a field radio perspective, this was also a good fun learning experience. The sun spot number was reportedly over 200 which I believe is for the first time this cycle (I am not certain about that). The conditions were thus a bit different on 40meters.
I took along my prototype T-200-2 coupler (see pics below) and was able to preform extensive tests with ZS4SF, my friend Monk in Welkom. Path distance would be an estimated 400-500Kms? On Saturday morning I deployed both the 31 ft quarterwave counterpoise along the ground and a .05 wavelength 6ft 6 inch counterpoise. My EFHW was higher than usual. The horizontal part was about 45ft long and at a height of about 20ft. The last 20ft sloped down to my operating position. The band was a bit unstable and thus QSB did play a part. The 31ft was receiving very slightly better reports than the 6ft 6inch counterpoise but the results really were very similar. The only difference was the same as I had seen at home and in my previous park deployment and that was a significant difference in bandwidth.
I was very pleased to note that I had no problems loading up the efhw and achieving 1:1 SWR with both counterpoises. No problem at all.
On the Saturday AWA net I received lower signal reports than usual. Mostly 579 and using 5 watts. I don't know why this was? It could be that the antenna was a bit too high for NVIS work? Or the high sunspot number was affecting propagation? A station from CapeTown om Adrian did call into the net and I copied 549. However he was unable to copy me. He was able to copy the Joburg stations but down in the noise.
On Saturday afternoon I erected a 10m dipole at 25ft and was able to copy quite a few DX stations. The band was mainly open to the west and this was the direction that my dipole was deployed. I managed to work one station in India on SSB. I was running about 8 watts. He gave me a satisfying 57 report.
This was also the first time I got to try out my new efhw with the launch cord connected directly. I smoothed over the joint with plastic steel. This makes it easy for the system to slide through the branches. I need to get one more length of the smooth light cord since this slides over the branches so much easier than the thicker cord. The only negative is that if a knot is pulled tight it is much more difficult to undo the knot with the thin cord. I am not sure how to improve this factor.
I also tried out my new modular dipole system. I took only a single center connector/hub. Then I was able to change the dipole lengths accordingly by screwing the different quarterwave lengths into the chocolate strip using my leatherman knife. I found this time consuming and a pain. Give me a doublet any day!
Observations and future actions.
- The efhw fixed component doubler definitely works in the field without having to tweek it. Next adjust the smaller T-50-2 coupler using fixed components.
- The quarterwave counterpoise results in greater bandwidth than the 0.05 wavelength counterpoise, however the performance on the air is the same.
- An efhw deployed higher does not appear to really improve local (NVIS) communications when compared to a 10-15ft high configuration.
- The new fishing weight launcher is pure pleasure to use and I cannot think of any way to further optimize it. This launcher can be easily tied to any cord using a reef knot at about 3 ft length.
- The modular dipole system using a single hub to reduce weight is time consuming to erect. Consider using a single wire that is marked for resonance on each band and that is simply rolled onto two shuttles at each end. This system I remember was used in the old days by the Rhodesian Army Signal corp with good success although it is heavy.
- A coil of wire at the end of a counterpoise does not materially affect the length of the counterpoise. Uncoiling a wire to different lengths and leaving the remainder as a coil at the end makes sense.
My Field gear for this trip.
Click on pic to enlarge.
Top Left:
- ~ Quarterwave counterpoise for 40m. 31ft in length.
- ~ 0.06 wavelength counterpoise for 40m. Approx 6ft 6inches.
- Four lengths of 20meter slippery cord including the fishing weight antenna launcher.
- Leatherman.
- Microphone for the K2.
- Cable for connecting to the CW Paddles.
- CW paddles folded away. Palm Mini paddles from Morse Express.
- Altoids tin variable QRP coupler for EFHW antennas
- RG58 coax. About 20meters.
- Short coax connector for coupler connection.
- Earplugs.
- Diploe center hub with 40m dipole connected.
- Quarterwave wires for 20m, 15m and 10m. Can be attached to the diplole center hub using choc strips.
- 12V battery cable for backup connection to car battery. (never been needed yet).
- A bag of different BNC and PL259 type connectors
Bottom Left:
- Pen.
- Small notebook.
- Box with prototype T-200-2 coupler
- Elecraft K2 full featured Kit Transceiver.
- K2 custom built carrying case.
- Small backpack for all the gear in this pic (except the K2)
Only in South Africa will you see cooking camp ware like this :) |
Tony doing his thing. This is a serious breakfast buddy! |
Prototype high power efhw coupler using a T-200-2 Toroid and 115 pf coax capacitor. |
Berry, Pat and Tony alongside the camping trailer. Superb! |
Pilanesberg National park. Click to enlarge. |
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