CQ 160-Meter Contest, CW - 2020
Call: K1LT
Operator(s): K1LT
Station: K1LT
Class: Single Op Assisted HP
QTH: Ohio EM89ps
Operating Time (hrs): 30
Radios: SO2R
Summary:
Total: QSOs = 1392 State/Prov = 58 Countries = 82 Total Score = 826,700
Club: Mad River Radio Club
Comments:
As I type this my CQ machine is chanting away and contacts trickle in
at 23 per hour although the rate picks up as we enter the final 90
minutes. I elected to operate assisted this year which might have
been advantageous since everyone seems to be CQing and fewer are
tuning. The spotting machines do all the tedious work.
While finishing my new phased array receiver design has been the main
project, there have been a couple of opportunities to try some new
technology. First, in order to build an expansion board to plug in to
the dedicated computer in the array receiver, I had to figure out how
to solder the high density 160-pin connector to the board I designed.
The required connected resembles a ball grid array chip in that the
pins are completely covered by the connector body and the requisite
solder is part of the connector assembly. Soldering this part was an
opportunity to try using a hot-air rework tool.
While attending the K8AZ open house at the beginning of January I was
chatting about this soldering challenge with a couple of people. The
thought occurred MicroCenter might sell a simple hot-air tool and it
turns out that the Cleveland MicroCenter is only about 5 miles from
K8AZ's place. So when the NCCers threw out the MRRCers Bill (now N8LT
- still digesting that new call) and I drove over and bought an Aoyue
(no known pronunciation) INT-968A+ hot-air rework station. This turns
out to be a fairly decent tool.
To practice my hot-air soldering technique I built another receiver
module for my growing phased array box. I even moved the expensive
chips from the first incarnation of the circuit board to the latest
version. But using the hot-air tool on connectors with plastic bodies
causes plastic damage because the hot air is necessarily much hotter
than the solder melting temperature. So hot-air was not the solution
for this particular challenge but the tool proved very useful for
other soldering work.
The next step was to try reflow soldering using a toaster oven. I
previously tried reflow soldering using an electric griddle and the
regular kitchen oven. Both attempts worked but both were fairly slow
at heating the solder and flux mix (called paste) which resulted in
less than ideal results. When the temperature rises too slowly past
the solder melting temperature, the flux tends to boil off before the
solder finishes flowing.
The answer to this problem is a toaster oven. There are a dozen
articles on the Internet about using toaster ovens for home reflow
soldering. The consensus seemed to be that for occasional hobby work
a cheap over and an oven thermometer are sufficient equipment.
The first oven I bought from Walmart took too long to heat up. I
didn't even try soldering with it. The second oven which was even
cheaper had quartz heating elements which spread heat via infra-red
much more readily than the standard elements in the first oven. I
used an oven thermometer to track the temperature but that particular
thermometer had too much thermal mass and lagged the actual
temperature by quite a lot as evidenced by the solder unexpectedly
melting on my first reflow attempt. Nevertheless the thermometer
shows that the oven's thermostat does a reasonable job controlling the
temperature, so long as one aims well below the solder melting point
and waits patiently for the temperature to settle before zapping the
temperature above the melting point.
The first attempt to reflow the expansion board with the high density
connector failed because I made an error in the board layout in which
one of the pilot holes did not permit the connector to sit properly on
the board which in turn prevented proper reflow. The second attempt
with a second connector and second board modified by exacto knife
mostly succeeded. Because I was still learning I didn't follow the
temperature profile well enough and not all of the solder flowed. But
I allowed for this in the board layout by including a via hole under
each pin. The hot-air tool and soldering iron plus an ample amount of
liquid flux seemed to always succeed in soldering a pin to a pad. I
just have to find all of them - only 160 pins.
So far I have made enough pins work so that I could add a 'real time
clock' and a frequency synthesizer (Si570 VFO chip) to the phased
array computer via the expansion board. I plan eventually to make
enough connections work to add some more receiver modules for a total
of 12 receivers serving 12 short verticals.
Second thing: now that I have 'mastered' reflow and hot-air soldering
(optimist speaking), I felt competent enough to try soldering the the
nifty relay controller chip I found to update my Ethernet relay
control board. I use these boards to implement remote antenna
switching and rotor control. The original design used a high-side
relay driver chip that went end-of-life as soon as I determined they
were useful. The new relay driver chip is available only in a
quad-flat-no-lead (QFN) package which has pads on the bottom of the
chip spaced 0.4 millimeter (compare old fashioned DIP at 2.54 mm
spacing) as well as a big ground pad in the middle of the underside.
Reflow soldering indeed!
Over the Christmas break I revised the Ethernet relay board for the
new driver chip and ordered boards. Various delays conspired and the
new board arrived Wednesday. I reflow soldered the chip onto the
board but then discovered that I used the wrong reference for the QFN
package footprint. Thus I need to revise the layout and order another
set of boards. But the hot-air tool unsolders the chip nicely and I
can still use the errant boards for other purposes.
How does reflow soldering relate to a contest summary? I had a blast
playing with the new technology and testing my limits. Adding the VFO
chip to the phased array box meant I could synchronize all of the
receiver local oscillators to get rid of the 1 Hz beat notes when
strong signals appear in more than one receiver output. The contest
proves that building this stuff works. This is amateur radio from one
extreme of building to the other extreme of operating.
Since my new north/south array consumed my spotting verticals, I tried
to hang the transmit signal nulling circuit from magic-Tee splitters
from 2 of the verticals. Apparently, though, the transmit signal
mixes in the array receiver mixers and generates lots of spurious
signals in the spotting receiver. Thus the 'full duplex' spotting
arrangement doesn't work any more. To compensate for the loss of this
capability, I decided to operate 'assisted' which would presumably
reduce the need for my own manual and often ineffective spotting.
I spent the first hour clicking and pouncing instead of running to
amass multipliers quickly so that the truly interesting multipliers
later would be more apparent on the band map. However Europe wasn't
answering calls for the first couple of hours except for MX5A. I
stopped trying after about an hour worried about my overall rate and
switched to CQing for a while. I periodically attempted DX QSOs and
found success with only a scattering of Europeans. Around 0045Z that
pattern changed and I logged a bunch of multipliers taking the total
multiplier count to 100 by 0200Z. After that I could alternate
between CQing and chasing interesting DX without much consternation.
I had the usual receiver configuration with 'northeast' in my left ear
and 'west' or 'northwest' in my right ear. I began the test with the
'south' array at slightly reduced volume 'centered' (both ears) which
works most of the time because that direction seems to be particularly
quiet. This made the Alabama and Florida stations particularly loud
which was nice because I often have to search hard to find them with
previous arrangement of just 2 arrays. On the other hand, maybe they
were loud because of conditions. Somewhat later in the evening, I
turned off the 'south' array because the automatic muting when I
transmit was not timed correctly and the quirky audio was annoying. I
figured I could fix it during the day Saturday.
At 0820Z I logged the last European and noted that I had mostly caught
up with my rate for 2019. Since I wasn't feeling excessively tired I
elected to keep going all night although I put the recliner in front
of the radio just in case. Maybe I dozed off just once.
Around 6am my Mom called me with a personal crisis. Fortunately her
crisis was resolved with a couple of phone calls with my sister and
the elder care contractor. But the distraction cost 27 minutes and I
failed to notice the potential benefit of waiting for 4 more minutes
before getting back to the radio.
At 1259Z I had 891 QSOs and had been operating 15 hours straight so I
elected a nap.
After about 4 hours I got up and tried to be awake. Eventually I was
awake and I fixed the 'south' antenna / receiver self-muting (mumbled
boring details). Everything else was working so I had a relaxing
afternoon worrying about whether or not the kid was properly ready to
go do Pep band at the high school basketball game. Fortunately
another parent gave her a ride.
Since I was thinking of operating another solid 15 hour block, except
for reserving 90 minutes for the very end, I elected to not to return
to the radio until later in the afternoon. But I failed. I resumed
operating at 2128Z. But I would take 30 minutes off when the rate got
too slow. So much for planning ahead.
While the rate might have been too slow, there was always something to
work. GM3POI was the first European at 2233Z, more than an hour
before sunset. After that the DX called regularly and anything on the
band map was easily caught. Around 0100Z UN9L showed up on the band
map. That's a new all-time band country for me! Furthermore, I could
hear him! Working him was not too difficult although W8AV and I
tripped over each other a couple of times in the process. My log
shows a 16 minute gap while I chased the new one.
A few minutes later RT9S was spotted. It took a little searching
around in the QRM to really find him but I could hear him too! Also,
the 'south' array switched to 'north' could hear him better than the
'northeast' array, which is good since that was the design. I missed
working him while messing around comparing antennas but a short time
later I worked RA9Y with my new capability. A little while later I
worked R8TT just because. Conditions or new antennas and equipment?
Hard to say, probably some of both.
Pleased with my new country and new DXing success, I spent the rest of
the evening CQing to try to make up the lost rate as compared to last
year. From 0100Z to 0500Z the 10-point QSOs outnumber the others.
After midnight the European rate began to decline and I logged the
last G station at 0651Z. At 0737Z I stopped for a 2-hour nap.
When I set the alarm clock I stretched the 2 hours to 2.5 hours. When
the alarm woke me up, I spent a few minutes wandering around trying to
really wake up. When I sat in front of the radio, I had a weird
experience. The screen showed me a callsign that I was supposed to
work, but the audio in my headphones didn't match. I could not figure
out why my eyes and ears could not reconcile the difference. Twice I
got up and drank some more water and walked around trying to figure
out what was wrong with me, each time making me more upset. I think
getting upset woke me up sufficiently and eventually I remembered that
I had to tap just one key to switch the audio from the SDR receivers
to the K3 so I could pounce on the spot the screen was displaying.
Now maybe I have a small introduction to dementia, the thought of
which reminded me of my Mom's crisis from the morning before. Getting
old has its charms.
So the extra long nap and the senior moment conspired to make my
2-hour off-time into a 3-hour off-time. I finally made a QSO at 1037Z
and after clearing out the pending spots I set up shop in the JA
window. Shortly after that I was called by NW0A who turned out to be
RW0A in zone 18 who was quite audible without the 'north' array when
the 'northeast' array was turned north (not it's preferred direction).
While CQing in the JA window, the spotting network kept taunting me
with new stations that I had not yet worked. A couple of them were
far enough away from my transmit frequency that I could work them
using the SO2V scheme and one of the Beverages. But most of the spots
were too close to my transmit frequency.
Give up my sacred hole in the JA window to make more QSOs or hope for
a JA call? There were spots for the big-gun JA stations, but all the
spots came from west coast RBN nodes. Would I be able to hear them?
Eventually I gave in and left the JA window at 1200Z. I cleared out
the spot backlog and found a new JA window hole. Now that I was more
awake and aware of the possibility of frequency freedom, I went
hunting for JAs. It turned out that I could hear JA3YBK and even work
him. The steerable stuff was showing him coming in on a slightly
skewed path which I've not noticed before. None of the other JAs nor
JT5DX were audible.
At 1340Z I stopped for another nap with 1:38 operating time remaining.
At 1957Z I couldn't resist the radio any more so I started working
stations again and started typing this extra-long winded dissertation.
The final 98 minutes resulted in 38 more 2-point QSOs. I could hear
EA6SX at 2140z when I stopped but I chose not to call him.
DX worked: 3V, 4O, 4X, 5B (2), 9A (6), C6, CE, CM (2), CT, CT3 (2),
CU, CX, D4, DL (60), E7 (2), EA (7), EA6 (2), EA8 (2), EA9, EI (2),
ES, EU (5), F (5), FM, G (18), GD, GI, GM (6), GU, HA (13), HB, HB0,
HC (2), HH, HI (2), HK, I (12), IG9, IT9 (2), J3, J6, JA, KH6 (2), KL
(2), KP2 (3), KP4 (2), LA (3), LU, LX, LY (12), LZ (4), OE (3), OH
(7), OH0 (2), OK (18), OM (10), ON (5), OZ (5), P4, PA (13), PJ2, PJ4,
PY, S5 (18), SM (7), SP (21), SV (2), TA, TF, TI, UA (21), UA2 (2),
UA9 (3), UN, UR (14), V3, XE (4), YL (4), YO, YU (5), YV (2), and ZF
(2) for a total of 84 entities. There were 950 2-point QSOs, 83
5-point QSOs including 59 VEs and 359 10-point QSOs.
Running yearly comparison:
.. Year QSOs States DX Hour Raw score Ops Asstd Pts/QSO
.. 2020 1392 .. 58 .. 82 . 30 .. 826,700 .. 1 .. y .... 4.24
.. 2019 1408 .. 58 .. 62 . 30 .. 588,720 .. 1 .. n .... 3.48
.. 2018 1275 .. 60 .. 62 . 30 .. 498,004 .. 1 .. n .... 3.20
.. 2017 1308 .. 59 .. 52 . 29 .. 460,095 .. 1 .. n .... 3.17
.. 2016 1210 .. 58 .. 54 . 28 .. 456,848 .. 1 .. n .... 3.37
.. 2015 1274 .. 59 .. 42 . 30 .. 374,609 .. 1 .. n .... 2.91
.. 2014 1199 .. 58 .. 48 . 30 .. 367,820 .. 1 .. n .... 2.89
.. 2013 1329 .. 58 .. 58 . 32 .. 536,140 .. 2 .. y .... 3.48
.. 2012 1297 .. 59 .. 47 . 30 .. 396,016 .. 1 .. n .... 2.88
.. 2011 1471 .. 59 .. 67 . 30 .. 670,320 .. 1 .. n .... 3.62
.. 2010 1559 .. 58 .. 75 . 39 .. 776,587 .. 2 .. y .... 3.75
.. 2009 1416 .. 59 .. 71 . 30 .. 757,510 .. 1 .. n .... 4.12
.. 2008 1350 .. 58 .. 64 . 38 .. 553,758 .. 2 .. y .... 3.36
.. 2007 1063 .. 58 .. 68 . 32 .. 422,100 .. 1 .. n .... 3.15
.. 2006 . 764 .. 58 .. 47 . 26 .. 260,505 .. 1 .. n .... 3.25
Hopefully the periods keep 3830 from messing up the formatting.
The running comparison above is useful to gauge conditions. I added
an 'assisted' column and I added an average 'points per QSO' column
which is the score divided by multipliers and divided by QSOs. This
year is 11 years since the magical year 2009 and is the first year
since then to beat the points per QSO metric. The question is how
much difference to attribute to conditions versus assistance.
One very notable difference between 2020 and 2009 is that I did not
have to struggle to copy callsigns. Nearly everyone who called from
Europe was readily copyable and the uncopyable ones gave up quickly
(maybe too quickly). This pattern has been noticeable all season.
Equipment: K3S/100, P3, K3/100, P3, Alpha 8410, 2x3 BS-EF phased
array, 2x4 BS-EF phased array, 2x2 BS-EF phased array, 60-foot "Tee"
over about 75 radials. Several Beverages of which only 3 were used.
Posted using 3830 Score Submittal Forms at: http://www.3830scores.com/
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