"> and Ukrainian stations also logged. (Remember, this was in July!)"
Hi George !
UY5VA and US4EX - tven in winter and summer they listen only on the
Internet !
They do not have receiving antennas.
QSO with Ukraine are not real.
73 !UY0ZG
andUkrainian stations also logged. (Remember, this was in July!)
GEORGE WALLNER писал 2018-07-13 05:19:
Dear Top Banders,
Here is a brief descriptionof the recent Baker Island (KH1/HK7Z)
160-meter operation.
Among the numerouslimitations the USFWS placed on us, being only
allowed on the island in June was the most onerous. A long way from
ideal from a low-band point of view, but we were determined to make
itwork. The result was over 1500 QSO-s on Top Band.
Transmit Antenna and Gear:
The location of the 160 m TXantenna was close to the north-west corner
of the island, but not as far north and clear of the land as we would
have liked it. Also, we were not able to place our TX antenna fully
inthe water, due to the pounding surf. (Which did destroy our 80 m
antennathe first night.) Instead, the 160 m TX antenna stood just at
the high tidewater-line, with the metal base buried in wet sand. At
low tide the antennabase was 30 feet from the water’s edge, but
fortunately the sand below theantenna was always saturated with
salt-water. Luckily, the tide was mostly uparound the times we were
working NA on TB. We were only allowed a maximum antennaheight of 43
feet. To meet this requirement, we designed a “fat” 160 mvertical,
which had three vertical wires, two of them on spreaders to make
theapparent diameter of the vertical conductor larger. The antenna
also had two12.5 m top-loading wires, which sloped down at 45-degrees.
The antenna had 8 radialsof various lengths, with three of them going
directly into the salt-water. Takeoff to the west and north-west was
clear over open water, but to thenorth-east (towards NA) it was over
land, with a 20’ high sand berm directly inthe way. The antenna was
fed via a remote-controlled coupler. I want to pointout that even this
simple, and far less than ideal, arrangement took atremendous effort
to build, as we had to haul the all the gear for the CW tentabout ¼
mile from the boat landing, working in 100 degree heat under
theEquatorial sun. Transmitter power was around 800 W (but
occasionally reduced400 W to leave more generator power for the other
bands). The radio was a K3S.
Receive Antenna: After thesecond night of operation we built a 60 foot
long DHDL facing north-east. Theantenna had a high-performance
filter/pre-amplifier. After the fourth night weadded a second DHDL
that faced towards Europe.
We were expecting easyconditions for JA (who were closer) and
difficult for NA. We got the opposite.The band would open to NA soon
after our sun-set (around 18:00 local time) withvery little noise. NA
callers were initially weak but easy copy. Noise wouldstart rising
about two hours after sun-set. Fortunately, that was about thetime the
gray-line was reaching the East Coast, which brought up the
signalswell above the noise. Some East Coast signals were quite loud.
As the eveningprogressed, noise continued rising as more of the
equatorial thunderstorms toour west came under darkness. By the time
the JA-s would show up (about 5 hoursafter our sun-set) noise was way
up, and receiving conditions were becomingdifficult. Still, some West
Coast stations kept coming in strong, well over thenoise, and quite
able to work among the numerous JA callers. Occasionally, wehad to
listen up for NA above 1825.00 to avoid the JA QRM, but on the long
runthat proved to be unnecessary. Overall, working NA was a pleasure,
whileworking JA (and SE Asia) was a pain due to the noise. By midnight
local timethe lightning crashes on the TX antenna were becoming
painful. Later, the DHDLRX antennas would help, but even then, many
signals were a better copy on theTX antenna. Almost every call was
different, some would be strong and clear onthe TX antenna, while
others could only be copied on the RX antenna. There wasalso a large
variation in RX conditions from night to night. On our secondnight the
noise was much higher than on the first night. Also, as we wereworking
progressively weaker stations, things were getting harder.
Although we knew that thechances for working western EU were basically
nil, we made a big effort to workas far west possible. On most
mornings the noise was just too much to copyanything below S7. A few
nights, however, conditions were favorable, and we gotas far as
European Russia. Conditions were the best on our last night, whenjust
at sunrise we got as far west as Serbia, with numerous Russian
andUkrainian stations also logged. (Remember, this was in July!)
After operating 7 straightnights on 160, my ears were ready for a
break. We switched to FT8 for about 5hours, using the regular QSO mode
(not hound-and-fox). With N1DG operating, wemade about 120 NA QSO-s in
about 5 hours! Just before midnight, we switched backto CW for the
JA-s, who are not allowed to operate FT8 in the lower part of theband.
The FT8 operation revealed three things: There is serious demand for
FT8on TB, the mode gets through the noise very well and gives modest
stations achance to work serious DX on TB, but it is easily dominated
by the strongsignals.
An interesting lesson fromwhat happened to our 80 meter antenna.
Initially, it stood on a sturdy metalbase in the water. During the
first night we had a storm and the surf broke upthe base (snapping ¼”
bolts like they were matchsticks). The surf knocked theantenna down
and soaked the tuner with salt-water. The next morning, we rebuiltthe
antenna further up the beach, but without the metal base which
originally connected it to the salt-water ground. Although we added a
good number ofradials, performance was poor, especially when compared
to the 160 m antenna,whose metal base was in contact with the
salt-water below.
The key lessons learned:
1. 160 m DX is morethan possible in June and July.
2. For good results, you mustbe on the band every night, otherwise you
may miss that special night when theconditions line up just perfectly.
3. A salt-water ground helps,and where possible, vertical antennas
should stand in the water. Being up thebeach is not the same.
4. RX antennas are needed towork the weaker stations.
5. DXpeditions should have astation dedicated to 160 m (at night) with
operators who want to work 160.
6. FT8 is now part of AmateurRadio, even on TB.
Happy DX-ing and 73,
George,
KH1/KH7Z (AA7JV)
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