All my limited understanding of HF propagation went on toss :). how much should be SFI for great openings on 10m?. SFI was 109 over the weekend and N0NBH solar widget showing 10m band as poor with A =10 K=4 etc and I did over 600 Qs just on 10m for the weekend!. I am really confused but even more amazed with what we didn't know happened at bottom of HF comms pyramid!. Is that Nature's miracle to keep Man amused and grounded.
Background:
Last 10 years in contests, I have not experienced a condition where Qs poured this heavy. Really.. there was no time to pee, even gulping water seemed difficult in midst of that high rate hours HI HI! and this is story for me of more philosophical revelation and may be a start of new era in Radio contesting years. A story of learning, struggling over years for location, evolution in antenna designs to suit locations, right frame of mind and finally saying - "this is all I had, now what?". - take it easy !
Last month, myself and VU3SPD - OM Vatsa did low power Multi Two SSB contest from this hotel in the northern outskirts of Bangalore. Location was quiet, radio friendly. Though it was not at high elevation, HFTA showed good signal probability at hotel's 30 to 45feet high terrace. I was suffering from heavy cold and throat infection for the voice contest. Some heavy tripping of W6PQL amp due to SWR issue lead to HP Blade ESP120 DC power supply problems. We made decent scoring of ~650 Qs. For last few years, I have traveled 350km to beach location near my native for CQWW, but this time due to MQTH, decided to operate from this known location nearby.
My amp was not giving out more than 150W with another standby power supply due to efficiency. W6PQL suggested to reduce amp VDD to 40V which can increase BLF188XR LDMOS output to 400W (for better efficiency at lower input power). I could not adjust the power supply below 46.5V due to limitations in that SMPS design. So amp was kept aside for CW contest. I started preparing my mind saying my highest till date was in 2015 that too with 50W power and now this 100W from rig is 3dB higher. So scoring goal can also be higher than that of 2015 to start with.
This also allowed me to relax, as when I travel with high power gear there is always some anxiety around local electric power issues, extra weight, SWR etc. I had done a presentation during Hamfest India 2022 where I mentioned about "Pyramid of HF Comms" with 5 layers. At the bottom is Ionosphere. My point was - to make comms successful, Operator at top is at the mercy of Ionosphere at the bottom and all other layers are instruments in between. With our limited understanding of Nature, we have to be in submission mode to be humble and accept what comes. - a hard learning over years. So we have to put efforts, learn and advance, but always have to be cognizant of the fact that we are tiny particles in larger context of Nature and what we don't understand (call it miracles?)
Setup
This contest seemed like summary of what I presented in text book style. My plan was to keep it simple, using homebrewed triband hexbeam with fishing pole and dipole for 40m.
Soon after hotel checking-in on Friday @7AM, I got to their terrace to unpack all antenna wires and coaxes. First was to set hexbeam. Clock work starts with my lightweight mast and center post assembly.
Many aspects of this were designed only for temporary setup and knowing that we have to be ready for any issues. One hour was my target and I did manage to complete assembly within that time. But tuning took another hour for SWR match.
Few days before the contest, I had modeled 40m dipole (4nec2) with one leg bent towards floor at 45deg, other in horizontal and checked adding a driver element. It all showed good 2.5 to 3 dB better gain and FB of more than 20dB. So why not carry wires?
There were two levels on terrace. One ~30ft high was adjacent to room and another above the room at 40ft. There were few wall clamps permanently fixed on the south sides which were used last time for spider pole support. This time, it was easy decision to use the same. Used 9 sections of 12mtr spider pole, attached choke at 7mtr point and dropped a thread from 9mtr point for holding director element. First tuned driver element to 6.88Mhz with director decoupled (dropped to ground). Then raised director at 15 feet horizontal distance from driver (distance plays role in FB and SWR which was adjusted to get best). All this took couple of hrs.
By lunch time, I was done with all terrace antenna work. My friend VU2CDP was also at an excellent field location near Pune for the contest. He kept chatting with me on his progress and challenges there.
Afternoon, I went on to setup working station. I also tried amp for power output with standby DC supply and decided that additional 50W is not worth keeping extra hardware on the table and dropped to barefoot 100W with my TS590.
Some more fine tuning of antennas for SWR and test of FB was done in the evening.
Desk looked neat and promising for upcoming contest day.
Contest-
As in my 2015/16 contest, first few hours seemed to determine the outcome and it did so here as well. First session on Saturday morning till breakfast at 2:30 Zulu ended with 59 Qs on 40m. This gave me confidence that I may be able to beat my previous low power scoring. Then started on 10m with Japan. What a discipline in pileups as well!. It was like some traffic cop sending them one after other. Continuous Qs till 3:30Z. Switched to 15m at 3:30Z with JA pileup till EU started popping/taking over around 4:30Z. Pileups on both 10m and 15m alternating when one slows down. Continued till 12:30Z on these and then switched to 20m. 20m was comparatively slow paced till 16:30Z with many NA popping in between. Whole night was spent on 40m with a 4hr sleep breaks. Later VU2CDP informed me that it was prime time for 40mtr. But I could not keep myself straight for both nights during that time. First day closed with 1K Qs in total.
Sunday started with good Caribbean multipliers on 40m such as V26K, PJ4K, ZF1A, PJ2T. Then kept runs toggled between 10m and 15m as per run rates. Maximum I could handle was 120 Q/hr on 26th. In between I thought "oh lord, I asked for good conditions and you are just pouring". Day2 also followed the same pattern of follow the Sun i.e. 40m till 2:30-3Z. 15/10 for JA till 5Z and then continue with EU on these bands till 12Z. Around 12Z, started checking 20m. Interestingly on day 1, 20m was not having big signals till late evening local (i.e 12:30Z). My reversebeacon.net spots showed good signs on all bands. With low noise floor, Except sometime after evening greyline, I could copy much weak signals. Some of those signals didn't even move the S meter needles on TS590. I closed my contest with excellent team at A44A on 40m at 23:57 completing my all band contact with them.
In no time, I was packing and by 2Z was on road back to my home reaching safely back and logging to MQTH remotely!
What are the learnings this time?
What worked very well-
Multiple field ops in last couple of years, helped to refine the go kit for contests
- Filter sets, Amp, Radio, Ant, Tools all in their respective bags
- Antennas are mostly for the location & situation with some enhancements
- Most of the clamps do not require any tool, use plastic butterfly handles for quick fixes.
- Minimal waste of plastic and ties -replacing with rubber tie wraps (inspired by bongo ties).
- Understanding of antenna models and tuning procedures for multi element yagis really helps in adapting to location
- HFTA is a boon before reaching the location, do physical recce for noise floor and friendliness
- Keeping the relaxed mind all the time and sharing fun bits with buddies during ops really boosts morale
- Packing from one contest is preparing for the next one. Keep the kits in shape after each contest - check wires/coax for damage, clean connectors, keep tab on spares (nuts, bolts, solder, guy ropes etc)
- Carry extra chokes with SO239s. it helped me to resolve RFI issue of USB audio connection drops for QSOrder
Out of all 5 layers of pyramid what matters most ?-
While multiple ops optimized instruments over time to some extent (rig, antenna and location choice), Top of pyramid - The Operator (who seems to be understood and under control ?) needs more refinement and higher level of respects to The bottom of pyramid - Ionosphere (The most illusive and not in control !)
Operator - Need to work on optimized schedule for night time shift, multiplier hunting, be smart to apply ideas for the situation
Ionosphere- We can only have general trends of signal path. But what will happen on contest day, no one can predict. Impossible happens within minutes. We are just witness of fine balance between Sun and Earth spheres
Operator is at the top of pyramid but he is really at mercy of bottom of the pyramid - The Ionosphere. But when all things go right CQWW CW 2022 happened to VU2XE setting higher bar for next time!
What about you? Did you experience the magic? Hope you enjoyed the thrill as well..
DE VU2XE Kiran
1 comment:
Excellent run-down on the operations Kiran. Lots to learn from your experiences and experiments with set up and planning. Hope I can join you on one of your activities soon to experience more
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