The preparations started in April when the 4L20m monobander has been dismantled in order to create space for the second KT36XA. I bought it used from HA0NAR Laci, purchased an upgrade kit from M2 and spent approximately the entire summer to clean/refurbish the old parts and make the upgrade.


Being confident of experience gathered during the previous antenna assembly; I simply moved the semifinished parts to the distant QTH without performance trial.. This decision costed eight full days (and nights) on the hill in wind and rain in a period of three months. Planned to participate in the SSB part, but the antenna was not ready by that time.


This part is for people planning to upgrade their KT34XA to a KT36XA:

The old KT34XA has several dimensional differencies compared to the M2..36XA. Before transporting to the hill the individual elements were sub-assembled in the garage and carefully marked. During the onsite installation though, the resonance frequency were off by 4-500kHz on 15/20m, but was almost perfect on the entire 10m. I would not detail each different adjustment step made during the three months; including the complete disassembly and rebuilding the antenna to its original specified dimensions; I was even comparing its physical lengths to the earlier installed antenna which works flawlessly from day one. (they were identical within 1-2mm in length, but still..) As consistent modifications of the individual elements did not lead to an acceptable compromise among all three bands; finally all have been reset back to drawing callout. At the end rootcause been identified was the length of phasing lines between the two driven elements. Infact, the assembly is straight forward in case all components are newly supplied by M2. However, when vintage KT34XA components are to be used; some of them are different in length, diameter and needs to be resized (cut) as per the new specs. (Even if M2 says it does not have any effect.. it really does have.) Neither the old nor the new phasing lines tuned the antenna to the published curves, but their implication made me suspect that is where I need to investigate. Without changing the distance between the two driven elements I started experimenting with extended length flexible phasing lines (insulated stranded wire). After a few hours of wire-chopping I was able to find the optimal resonance for all three bands.


Besides the "antenna bug" there were a few more Murphy's this year. But, at least I did not tear my biceps off this time. The night before the CW round the main amplifier has blown fuses twice and made me think I should use the spare for the contest after cca. four hours of repair and trials. A complete board needed to replace later.

Earlier the year I have taken lessons online to learn ten-finger typing. On a Hungarian keyboard the position of the Z and Y are reverse to the English one, so I needed to replace my "old ham keyboard" to a new where the letters are at the "right" position.. The old one had PS2 plug the new has USB... and it does not like RFI... One hour before the contest a few turns of keyboard cable thru a snap-on ferrite did not seem strong enough to stop a repeated CQ... Once I started to transmit the keyboard lost its connection with the PC.. Fortunately, this happened only on 20m where I was mentally set for a year to participate. The gear was sharpen for single band assisted high power category with inband so2r; all pieces tested in advance, but the keyboard..

I gave the thing one last chance 30 minutes before the start; checked the setup for 15m, found no RFI there, downloaded quickly a propagation prediction and drafted the first 24 hour operating strategy. I should say I was lucky with this option since I gained a few extra hours before the band opening. Otherwise I could have started immediately a 48 hour session on 20m with zero sleep. These last couple of hours though, made me think a few times it had been better to pack and go home.

At 00UTC I went to bed finally having in mind "I owe somebody with this" feeling and had a very good sleep.. while others started the contest.

15m had decent conditions during the entire weekend; except the Sunday closing that came earlier than expected. The recently installed satellite internet worked flawlessly throughout the contest providing enormous amount of RBN data for S&P enabling me to collect 154 countries and 39 zones. Multiplier hunting was much different with the inband SO2R than anytime before with the 2nd VFO. Shack ergonomics have also been improved since the last event, made me less exhausted by the end. The QSO count became 2,010 adding up to a total score of 872,030 claimed. It looks to be enough for a world 10. / Eu 5.


CU soon in ARRL DX CW.




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