CQ Worldwide DX Contest, RTTY
Call: AC0C
Operator(s): AC0C
Station: AC0C
Class: SOAB HP
QTH: Kansas
Operating Time (hrs): 35:54
Radios: SO2R
Summary:
Band QSOs Pts DX S/P Zones
-----------------------------------------
80: 84 106 8 8 39
40: 313 622 52 14 40
20: 461 718 50 20 51
15: 551 1284 65 21 35
10: 60 164 32 11 5
-----------------------------------------
Total: 1469 2894 207 74 170
Total Score = 1,305,194
Club: Kansas City DX Club
Comments:
Being away from radio for 27 years, today’s contest was the hottest I’ve
seen the bands on a contest weekend since I was a kid.
77 DX is almost a DXCC in a weekend (something I’ve always wanted to do but
have not hit it yet!).
It was really great to see Sunday’s SFI/A/K numbers so ideal. Thanks to
everyone for the Q’s. See you on the next big one!
With these band conditions, Q-rates are going to be nice. Ed will probably
have hit 10K Q’s with So3r going. hi hi. My Q-rate reflected first-time
So2r jitters, macro adjustments on the fly, rig and hardware tweaks. Tough
parts were lack of sleep as the push to finish the So2r setup took longer than
expected and with some frustration for having planned on a 15/20m day-20/40m
night contest - that turned out to be a 10/15 day and 40m night challenge
instead.
That’s one of the things I enjoy about contesting â€" a chance to see if the
work you did on the shack pays of on game day...
=================================================================================
Equipment:
FT-2000 with NS roofing filter, FT-dx5000MP
SB-200 with Gi7b, Alpha 76pa
Attic-based So2r 80m dipole, 40m 2 element phased, 20m 3-ele reversible, 15m
3-element bi-directional + 10m fixed east
N1MM, 5B4AGN BPF, Microham
The FT-2000 with the NS filter was an outstanding performer with about 1/2 the
Q-count logged on that box. The FT-5000 worked great and has a lower noise
floor than the 2K but I had really not noticed it much until the unique high
SFI and low K/A condx we enjoyed this weekend.
Ran some So2v with the 5K. The 2K with some sub mods is a better So2v box but
I have not setup the sub rx AF loop yet. I much prefer So2v on the 2K because
the interface is much easier. The width control on the 5K requires pushing a
button to change between DSP width ranges which is very tedious (the 2K
firmware is more logical from that standpoint). Hope Yaesu will fix that in a
future update...
After some trouble with the SB-200 amp (tracked to a loose wire on the bias pass
transistor) earlier in the week, the gi7b-based amp was a real workhorse giving
900W all weekend with no complaints. I had been meaning to swap the tank in
that amp but never had completed it and the amp’s been sitting for the last
year since I picked up the Alpha. The Alpha was solid as well but it’s not
nearly as filled with mods as the SB-200 is... Since the last contest,
internal RFI improvements and variable fan speed algorithms have been updated.
And following a small drop in HV, the PS caps replaced last month. It hummed
along without complaint as usual.
So2r and Antennas:
The So2r facilities are new for this contest having been completed just a
couple of days earlier. Having spent a couple of years building an attic system
that decoupled all wires not in the current band, the requirement of So2r (with
2 active antennas) was a lot more complicated than is normally the case. To
simplify the task, the FT-2000 is setup to work only on 20/40 as I had not
expected 10m to be a factor.
Now I have a lot more respect for the high-band magic the old-timers talk about
but that I’d never experienced. And this contest was dominated by 10 and 15m
yet my prior prep had focused on 20/40m. Clearly some revision of that design
decision is in order! Some of the 10m Q-counts on the early 3830 posts are
just unbelievable.
The 40/20 beams were unchanged for this contest beyond being wired as
enabled full time to support the So2r. I had planned to align the 15 and
10m antenna elements with the W8WWV RVM system - the west-pointing direction
has never worked properly but I ran out of time. And instead, the west facing
element was trimmed as a director with a MFJ-259 a couple hours before contest
kick-off with the hope of giving the beam a figure-8 bidirectional pattern.
Nothing was done on 10m â€" in fact that aspect of the array is essentially
untested. It was great to see the west side contact count on 15m with a lot of
JA and west US in the total. 80m was tough but a lesson from a prior contest was
that 10/80m need to be worked because early on, almost all the Q’s are mults
as well...
So2r specific hardware added included a pair of 5B4AGN W3NQN-type BPF filter
modules, KK1L 2x6 antenna switch and some switching interface retrofits to the
attic control box. Guys interested in more details - please visit the ac0c.com
web site - click on the So2r tab. There are a lot of gremlins remaining to be
dealt with before the ARRL RU. Unlike a single TX effort, the big challenge of
doing an attic-based So2r is tracking down all the items acting as harmonic
generators. Prior to this, guys would laugh about a lose drain spout or rusty
nail providing diode action - but when your antenna is in the attic, the
potential number of potential problems is just unbelievable. In the two days
running up to the contest, devices that were re-radiating with some amount of
harmonic energy included a down phone line, some inadequate common mode
filtering on the 40m phased array, a couple of switching mode power supplies in
the house - and even a neighbor’s digital to analog tuner.
Big list of to-do’s compiled and as Don says, “Always Be Improving.” If
I can get Don to come and do some attic work, that would be great as well. Let
the rusty-nail-hunt begin! Oh, and time for a serious effort on the 15/10m
antennas. Going to be a busy few months. The great thing about attic antenna
farming - fowl weather from the fall/winter onset is nothing a warmer shirt
can’t address.
73, Jeff ACØC
www.ac0c.com
