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Full text of "jh1krc A Moon Bounce Experiment With A 32m KDDI
Cassegrain Antenna
"
See other formats
A Moon Bounce Experiment With A 32m KDDI Cassegrain Antenna
And A Special Station 8S8NIEME
Mike Watanabe, JH1KRC
Project BIG-DISH 2007
< The First Approach >
One day in June, 2006, a local newspaper of
Ibaraki Prefecture revealed an unexpected plan that
KDDI satellite center would close their operation by
the end of March 2007. This scoop was spread
immediately by a local moon-bounce operator, Kony
Nemoto, JM1GSH, through the JA-EME network.
A proposal was initiated in a few weeks; how
about amateur radio moon-bounce experiment using
a huge dish antenna of KDDI? Next month a group
of Japanese amateur radio enthusiasts met for their
special planning at KDDI-Ibaraki Satellite
Communication Center in the Grid Locator QM06,
Takahagi City, Ibaraki, Japan.
al
Some twenty amateurs had the first EME meeting
at KDDI Ibaraki, July, 2006. IBA-5 in the back.
This Center was built as a communication node
for Intelsat and Inmarsat services, and has several
immense parabolic dish antennas and associated
infrastructure buildings for administrative, research,
construction and maintenance purposes.
KDDI offered IBA-4 §82-meter cassegrain
reflecting dish was oftered for radio amateurs’
moon-bounce.
Yuki Uchiyama, JH1INBN, a well-known DXer
and an active DXpeditioner, and also a good friend of
Mike for years, was one of the first persons to contact
with. Yuki presently works for KDDI and had a
carrier at the Center years before.
By that time, not all of KDDI antennas were in
active service; some already being in stand-by
mode. This situation made Japanese radio
amateurs possible to plan a historical moon-bounce
activity. Along with an approval, a favorable offer
from KDDI was given for the creation of radio
amateurs’ “Big Dish” project to communicate on the
usual amateur frequencies via the moon, using
IBA-4 32-meter cassegrain reflector dish antenna,
one of the KDDI’s main antennas.
A special taskforce consisting of Japanese radio
amateur moon-bounce enthusiasts was formed to
solve technical and logistic problems associated with
this project. Later, engineers from Czech Technical
University in Prague were invited into the team for
consulting and designing of the primary antenna
feeds for amateur frequencies.
Yuki and Mike had talks with KDDI stuffs and
engineers from Mitsubishi Electronics Co. who are
responsible to maintain this antenna. Mike felt
that the first approach was well-done and close to the
success. Later, a president secretary of KDDI told
us that one of the vice-president of KDDI strongly
supported our activity. She was so clever to have
had submitted our document of the EME plan to the
vise-president, which must be the first key to open
the door of success. TNX!
Some twenty JA-EME amateurs conformed this
project, naming it “the Project BIG-DISH”. They began
to discuss how to proceed the experiment through an
email network, as well as a web-site of the Project,
constructed by Bunshiro Tamura, JA5FNX, who also
maintains JA-EME web-site for many years. Those
enabled the Project BIG-DISH to work on solving the
many problems associated with launching its station on
the air before this KDDI Center totally closed their
operation within a half year.
We thought there had to be some specific reasons in
this case to approve for the special EME license. The
purposes to use this antenna for the moon-bounce aimed
the following:
@ A precise, large-scale antenna is used for amateur’s
advanced EME. (A professional antenna was
formally used for the first time in Japanese history
of radio amateurs, not only for the EME, but also
simply for radio amateur transmission!)
@ EME contacts to small stations are intended.
@ EME exhibition to radio amateurs.
@ Scientific exposure to young generations such as
school children and technical school students.
KDDI and the Project members are willing to invite
audiences to come and see our EME communications, as
well as to attend the lectures on space communications
and history of this Center which is thought to be a
milestone of Japanese international telecommunications.
We named this activity as a Moon-Bounce Class
Room under the BIG-DISH.
No one of the EME project members doubted this
activity would become a milestone of Japanese radio
amateurs, too.
In the middle of December, 2006, the Board
Directors of Japan Amateur Radio League offered the
Project for the support to obtain the special license.
JARL, KDDI Corporation and the Project BIG-DISH
formally signed for an experimental cooperation using
KDDI's 32-meter Cassegrain dish antenna.
The special EME licenses were approved to the
Japanese governmental Bureau of Telecommunications
for the maximum high power output of the legal-limit.
The experimental EME operation was planned on the
usual EME frequencies, such as 144, 482, 1296 and 5760
MHz bands, in CW, SSB, and JT65B modes. On each
band we requested 500 watts of output power to achieve
huge hundreds of kilo-watts, or mega-watts, EIRP.
Such an extraordinary high power was intended to make
our signals easy to hear by small antenna stations off
the moon. This license was issued in a few months
after several serious exchanges of opinions with
Telecomm officials. But 5.7GHz license had to be
approved separately; because our 1296MHz dish feed
totally covers an opening of the original feed horn used
for 5.7 GHz operation.
In the Japanese traditional telecommunication
administrations, even for radio amateurs, you cannot
preliminarily apply for, or cannot obtain an operation
license for the bands and/or modes which you cannot
actually transmit when the license is issued. Someone
from the Bureau of Telecommunications would come and
see what should be going on in your radio station every
time before the license being issued. If your
transmitter of a certain band is still under construction,
you have to apply for the license another time for this
transmitter and for the band, again. How silly, but it’s
areal system! Ifyou move your QTH, or you increase
the output power from 50 watts, for example, to 100
watts, you have to do the same as above. For what?
After negotiation with JARL and the Telecom, we
were fortunate to obtain a special callsign 8N1EME for
this event, representing the EME activities by a special
licensed amateur station. In Japanese radio amateurs’
history, this became the first time to operate from the
commercial site using the professional antenna.
< About IBA-4 Antenna >
The IBA-4 (pronounced like iba-yon) meaning the 4th
antenna of the KDDI Ibaraki Satellite Communications
Center, is one of the main cassegrain antennas. It was
originally designed for the satellite communications in
C-band, between 4 and 7 GHz satellite band. This
antenna has the weight of 380-tons without wind load,
the height of the elevation hinge at 25 meters above the
ground, is fully rotatable about 370 degrees in azimuth,
and can be elevated up to 110 degrees. These
specifications are undoubtedly suitable for amateur’s
moon-bounce communications. Automatically
programmed moon tracking is also available by the
original minicomputer, using punched-out tapes. The
nominal mechanical accuracy is within 0.02 degrees
each. You would input the moon data of every 30
minutes, so that the minicomputer would calculate and
almost smoothly compensate the moon path of every
second. FIEHN’s program was used to obtain the
data of the moon orbits.
No one doubted that we were sure to use this original
antenna system for 5760MHz successfully; since IBA-4
had both right and left circular polarization wave-guide
feed lines, and good pass-band characteristics for our
band as well. There were a couple of 83kW TWT
amplifiers in the antenna pedestal room where our
shack is located, but we were not allowed to touch them.
< Antenna Modification >
The largest problem we met was that the cassegrain
sub-reflector, 2.9 meters in diameter, about 9.6 meters
in front of the main reflector was not able to be removed.
The primary focus of the main reflector is far beyond the
sub-reflector vertex. According to the agreement with
KDDI it was strongly prohibited to remove even a single
bolt or nut from the present antenna. Therefore we had
to drive this sub-reflector in some way to illuminate the
main reflector for the EME operation. The actual size
of the sub-reflector, 2.9m, seemed to be too small as a
cassegrain reflector for 70cm band, but large enough to
decrease the antenna gain by the mal-positioning of the
feed point for the primary focus feed to be used.
Yoshiro JA4BLC and Yoshiyuki JA6XKQ were so
helpful to advise how to think about the dish feed
position, but had no enough time to solve all the
problems in the antenna modification.
Rastislava (Rasto) Galuscak, OM6AA, and Mike
began to talk about the antenna feed design. They
continued to exchange over 250 email correspondences
discussing the proper and possible feed designs. There
was no time to exchange one feed model to another for
comparison. The electrical and mechanical
modifications were once designed and built, we had to
use them till the end of the operation. This means
there was only one chance for the success.
Problems we encountered and the solutions
concerning to the design of primary feeds were later
described in the DUBUS magazine, No.4, 2007. The
Japanese translation of this article was published in the
Japanese CQ ham radio magazine, November and
December issues, 2007.
With a great help from Rasto our feed design for the
IBA-4 modification reached to the conclusion. It shows
the antenna gain of 28.5dBi on 144MHz, 34.3dBi on
432MHz, and 48.5dBi on 1296MHz. The original
IBA-4 antenna would make it 64.8dBi on 5760MHz
without changing the feed. The beam-widths of
1296MHz and 5760MHz are 0.2 degrees and 0.1 degrees
respectively, narrower than the optic angle of the moon,
ca. 0.5 degrees.
< The Hard Days and Nights >
The mechanical construction for modifying the
antenna feeds for the EME operation was planned in
early February, 2007. The taskforce members who
owed to build up each of the actual antenna feeds and
the associated parts had to make it Aurry. Mike
JH1KRC had to brush up a 2.4m US army surplus dish,
prepared for 1296MHz. Shigeru JH1EFA created the
arms to hold a substantial round septum feed, made by
OMIATT, accurately in the focal position, and
well-designed dish holders to fix this army dish on the
tip of original horn aperture in the center of the 32m
main reflector. (If it would drop off or slip away, we
had to compensate all the possible damages to repair.)
Koichi JJ1NNJ built up a water-proof box of plastic
material in which LNAs and relays for 144/432 MHz
were installed. Noriyuki JHOWJF, who often wins in
the CSVHF noise figure contests, had prepared LNAs of
very low noise characteristic for 482 MHz.
Kony JM1GSH holds 2m/70cm loop feed.
A unique two-band loop feed was designed by Rasto,
and built up by Mike without using any metal material
except for the 10mm copper tubings and thick coax
cables. Mike had to make it after he returned to his
dormitory late in the night. Fortunate enough he had
no claims from the neighbors to the noises of drilling,
hacksaw, and hummer Mike made nearly in the
mid-night.
Farfield
enabled (kR ¥ouel
farfield (f
Abs
Directivity
144
6.9885
@.9869
8.336 dBi
indeterminable
144MHz mete —TO Ba HE
Radiation pattern of 2m loop feed reflected
from the original sub-reflector of IBA-4 used as
a ground plane, a trade-off for the 2-band feed.
Along with antenna feed construction, Kony, Mike
and Shuko 7M2PDT had to be involved in the
documentation work and spent for hundreds of hours to
obtain the EME operation licenses.
Early in the New Year 2007, we got ready to submit
a volume of documentations including the transmitter
design and block diagrams, specifications, the methods
and data of spurious suppression, etc. The telecom
officials were so kind to request us, in addition, to
submit the detailed explanations on the calculated
antenna design, and the moon-bounce link budget for
each band. And they also kindly requested us to
show them the radiation characteristics of our modified
IBA-4 antenna, in order to see whether or not our
antenna beam patterns and transmission power would
satisfy the present radiation hazard control and safety
regulations. It was not a surprise; Japanese telecom
uses to request amateurs to submit these
documentations for a common amateur radio licensing
(especially for high power, or for EME). If you can
submit them, they would issue the license, and if not, the
license would be impossible.
Fortunately the KDDI’s communication site already
had, from the beginning of the history, been located in
an ideal place for space communications on an isolated
hill-top without so many neighbors. Later, at least
Kony and Koichi visited two neighbor families who live
next to the site, to inspect if they had any TVI, they
welcomed these unusual guests with great pleasure.
< Antenna Construction >
Not only the local amateurs like JAIBGU, JK1KXH,
JHOXHL, JEIBNZ, etc., our friends from far places,
JAOTJU and his son, JA7AGU and JH7SIA came to help
us. Cable placement through the rotary sections on the
antenna hub and pedestal was a hard job, but finished
very smoothly by these experienced amateurs.
We hired a heavy crane lift of 50-meter, 2-ton, which
was costly, 120k Yen for each day, but it enabled the
antenna construction really prompt, safe and pleasant.
Every heavy or large material was put in to the IBA-4
dish surface by the crane lift.
The 2.4-meter military dish was put in and fixed
onto the horn aperture with 6 pcs. of well-designed
clamps. 2m/70cm loop feed was hang up by the
professional workers. The suspension ropes were
pulled like “marionette”, and tied up so that the loop
feed was fixed in the proper position.
The climate of this Pacific Coast in Eastern Japan in
winter seemed to be very fine, warm enough and clear.
All construction procedures necessary for our operation
ended only in four days without any trouble. So it was
the time for the “marionette theater” open.
After the antenna construction was finished in
the mid-February, S8NI1EME began to _ test
transmission to avoid any interference to the
satellite communication equipments here and
around. Our transmitters were equipped with
harmonic filters and had cleared the harmonic
suppression of -70 dB. When we test-transmitted
432 MHz, an engineer in the KDDI operation room
phoned us that their C-band receiver equipped in the
same room as 8N1EME detected the very strong 9b
harmonic on 3888 MHz. His voice was vibrating,
express full of anger (or fear?). The receiver was
connected to the wave-guides of the same antenna
that we used. (It means they do not use this C-band
system. Why didn’t they turn off the receiver?
Actually, they cannot.) We had never imagined
that we had to suppress the 9» harmonic from Henry
amplifier down to undetectable level to the C-band
high gain receiver on the same antenna, but we tried
it. HP spectrum analyzer was no use; because the
harmonic level was already too low in the display.
1296MHz transmission was more severe in this
situation to suppress the 3"¢ harmonic onto 8888MHz.
Precise coaxial band-pass filter helped a lot, as well
as the HPA unit we had employed, using
8xFLL300IL2 GaAs-FET’s operating in the class AB,
but the 34 harmonic did not totally disappear.
Finally they abandoned it, and the harmonic
problem was totally cleared up. They now
understood that their C-band receiver, with its horn
aperture being wholly covered by our 2.4m dish,
received with its full-gain. So far we were lucky
that we did not burn the KDDI’s expensive receiver!!
In the evening one day before the telecom
inspection, everything went on well until the
moment when Mike was tuning the power hybrid in
the 1.2G HPA output for the final adjustment. A
send-key cable of HPA dropped off and came into the
gate bias power supply. It badly shorted a high
voltage section of the gate bias circuit, and several
hundreds amperes of drain current flew. It was
fortunate this GaAs-FET amplifier did not get any
damage, except for all the IC’s in the bias supply,
and the T/R change-over sequence circuit totally got
short.
At that night, the T/R sequence circuit had to be
built up for replacement with ordinary mechanical
relays and capacitors, and the gate bias supply had
to be changed to another in the bath room of a local
hotel where Mike stayed. The brightest area in
the hotel room was the bath room. Putting the
toilette lid on, Mike sitting on it, the repair was
finished well in time for the telecom inspection to
begin from 10 a.m. the next morning.
MYM
ii
Testing the 1.2GHz GaAs-FET HPA installed
In a water-proof box atter the over-night repair.
JH7SIA smiles in the pedestal room of IBA-4.
February 23, the EME station was inspected by
the people from the governmental telecom for the
operation license to be issued immediately. During
the inspection 8N1EME was asked to have a contact
via the moon. The very first but pleasant EME
contact was made with JA6AHB on 432 MHz CW.
This ceremony was performed by Koichi JJ1NNJ.
Our EME operation began in the afternoon of
February 28, first on 482MHz, and other bands
followed. The operation was very limited in time
because most of the amateur operators live far from
the KDDI Center, and only limited number of KDDI
stuffs could control the IBA-4 antenna. We were
not allowed to come in to the control room, so we had
to choose the operation dates, mostly on the
weekends when the moon conditions were favorable,
and ask KDDI stuffs to work with us during the
moon time for the days/nights. It lasted until the
end of March in 2007.
Shuko 7M2PDT and Koichi JJINNJ were the
main operators for 432MHz. For this band, the
antenna efficiency was calculated to be only 13 %
because of the defocused position of the loop feed.
In order to make IBA-4 a tri-band antenna, this was
a compromise we chose. Still on this band total
antenna gain was 34.3dBi, not too bad. While
Koichi operated CW, Shuko did mostly JT65. It
seems they worked out almost all the stations on the
band, and finally there was no station calling at all.
Defocusing caused certain gain loss on 144
MHz also, but the degradation was not so much as
on 432. The antenna efficiency was 31% and the
total antenna gain was calculated to be 28.5dBi,
which should become one of the largest antenna on
this band. Even an SSB echo was clearly heard.
Kony JM1GSH, Yasu JH2COZ, Hide JH5FOQ, and
Shiro JHOMHE enjoyed mostly operating JT65, also
many QSO’s in CW as well. See the dog pile-ups in
the screen shot. It lasted until the Jast moon set.
07 Feb 25 144MHz Pile up 16:15Z
hho 7 800 S00 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 260
Renee eevee Renee ENEWNAUEHMOUTWS OWENS MUNeN OWnuY SUmnY ONUNS OWENS ORT MUOTEMIATHOIRT ECR RTREM AREER ON EO
(tn
YOSFRJ YOSFRJ
sour Pde RAJHON sVBcs ~15d8 13
DK3WG DL7FF “14dB 1508
-16dB -16dB
COKBBAKA AVP ITPA, LIZOTADAY LE CRU T=
RE SRS Sicha “
{ # rT P\ Tt pt of
SMBSCFS OH8KLY YUICF call? call? fIK7EZN|RUIAA call? YOOFRU
-15dB 20d! “10dB 9908 -25dB | -10dB | -6dB ~29dB RRR
ait YUTAA
A unique triple reflector configulation on
1296MHz worked quite successful. 2.4m Army dish
with a round septum feed, made by OMIATT,
illuminates the sub-reflector to achieve the edge
taper of 11dB for the highest antenna efficiency on
this band. This made the total antenna gain of
48.5dBi on 1296MHz.
There are several 23cm op’s who pushed our
S-meter to the red zone. But in this time, the
strongest echo was that of 8NI1EME, perhaps +10dB
or more.
Directivity_Tot[dB]
This configulation provided a very low noise
temperature characteristic. Rasto wrote; For the
Earth temperature TO=290K, the noise temperature
of this antenna calculated at the elevation angle 5
degrees would be 35K. As the elevation becomes 20
degrees, the noise temperature would be 8K or so,
which is very suitable for EME communications.
But such low noise characteristic sometimes
might give misunderstanding. Once we found the
signals and the noise suddenly came down, and only
very weak echo of 8N1IEME was audible. Our
receiver became very quiet. It used to hear our echo
with S9++, and several dB’s of the moon noise during
our operation. So we thought that our LNA,
NF=0.2dB, made by HB9BBD, had to be badly
damaged. It happened in the culmination hour.
The next morning we checked our whole system,
but found nothing defected, except for the antenna
positioning at the moon in the meridian passage
when the IBA-4 tracking program did not calculate
the moon position exactly, just about 0.5 degrees
away.
Unfortunately in the first few days we had no
microphone, but mostly on 1296MHz, both SSB and
CW sounded very loud and comfortable like 20-m
QSOs.
< Moon-Bounce Class Room>
March 3, 2006, there held an open-house
exhibition and lectures to 150 audiences. The
Project asked to people who would like to join our
event on the web site, first limited for 100 seats.
Only one and a half days was needed to full-fill the
seats. So we had to increase it to 150. But one
more day was enough to stop reservation for the
seats.
There held lectures on satellite communications,
and on the history of this Communication Center by
KDDI stuffs, and on amateur’s EME by JH2OZ, and
about the Project BIG-DISH by JH1KRC.
After the lectures, from 1730 local time when the
full moon was at 5 degrees elevation in the east, the
special Moon-Bounce Class Room under the
BIG-DISH was held on 1296MHz, SSB.
Audiences were surprised to listen to the strong
echoes of 8N1EME, and those of U.S. cooperative
stations like K2ZUYH, K5JL and K9SLQ. School
boys and a girl came to the operation seats, and their
names were announced by Mike. U.S. attendants
came in to say hello to the school children. These
events were broadcasted by NHK _ network
world-wide.
Among the children there came a boy of 11 years
old who told Mike that he has the First Class
amateur operator license. Mike asked him,
“Really?” four times, according to the boy’s father.
Mike immediately changed the operating position to
the boy, Hirotomo Nakamura, JQ2LVT. Hirotomo
contacted with K5JL, which could be an EME
contact by the youngest amateur all over the world.
Our low bands operation ended soon after the
moon set of early morning, March 5. We had to
dismount all the antennas from IBA-4, so that we
would prepare for another licensing for 5760MHz.
If we had missed that day, we could not have got
ready for it. As soon as we finished disassembling
all the antennas before 11 a.m., suddenly a very bad
storm began with strong winds and heavy rain.
We were saved again.
<5760MHz>
How could you expect the signal strength of
1,200,000kW EIRP off the moon? Soon after we
got the license of 5760MHz with this EIRP, possibly
the highest EIRP (63.84dBi, 500 Watts TX output) in
the amateur’s history, we had to wait for the
moon-rise in that night (because we drank so much
for the cerebration, and could not go home). We
transmitted for echo testing for the first time on this
band, only for a minute. A weak echo was heard.
We found our LNA/converter gain seemed too low.
But it was surprising; there came an SWL report
from Charlie, VK3NX, that our signal was very
strong but had remarkable frequency drift. Yes,
we had some incidental frequency drift, and we
moved the transmitting frequency manually to tune
to the HP frequency counter!! Mike took back the
LNA’s and repaired with new FHX-35L@’s.
Our final operation began on 5760MHz in the
morning of March 24. Our echo became very strong
with the LNA’s, one repaired, and another one from
JA6CZD. We were lucky to find W5LUA testing.
8N1EME began to call CQ near Al’s frequency. He
replied soon.
Al wrote, “There was a very strong signal on my
frequency. It was stronger than any other EME
signal on any band that I have ever heard. I was
blown away!!” Al thought it should be his local
station. We exchanged the signal reports of 599’s
each other.
JA4BLC, JR4ZZS, JA6CZD and JA8ERE
followed for their fist EME QSO’s on this band.
In the night, Europe window was very busy for
the DUBUS Contest. Most of signals were really
strong, S9+, S5 to 7, etc. Among them there was a
weak signal calling; GM4ISM with 449. He gave us
559 for the first GM(or Great Britain)/JA contact.
His antenna was 1.8m dish, specially prepared for
this contact.
The next day Al tried to hear us with a horn
antenna of 27cm aperture, and he did hear our
signal partially. The last two QSO’s of 8NIEME
operation were shared by VE4MA and WD5AGO on
this band. 8N1EME sent TNX and 73 by Mike at
0509UT, March 26, 2007, and went QRT from EME.
According to the calculation of link budget we
presumably made, 8N1EME had to have contact to
small stations. We succeeded to work some of such
stations with small antenna and small power on
144MHz and 432MHz, like JF1DMQ with 2-yagis,
45 watts output on 482MHz.
Since hundreds of microwave enthusiasts were
active in Japan, we asked them to listen to our EME
operation on 5760MHz. Several SWL reports
came in; most of successful receiving were done with
small dish antennas, from the size of 45cm to 300cm.
Larger dishes like 2m, or 3m sizes were tried in some
cases but it seems for them to be more difficult to hit
the moon. According to the link budget we
calculated, 8N1EME might have a QSO with 2 watts
output (Japanese legal-limit for ordinary stations)
into a 4m dish on 5760MHz, but no one did it.
There still remains a question that a station with
large scale antenna, whose beam width would be
much narrower than 0.5 degrees, might have certain
degradation in receiving power. Unlike we aimed
at the beginning, this question was not clearly solved
yet.
Project “SMALL-DISH“ by JJINNJ at
8NIEME‘sitre during the 5760MHz operation
Total EME QSOs: 323
144MHz: 154 (CW 11, SSB 1, JT65 142)
432MHz: 57 (CW 34, SSB 2, JT65 31)
1296MHz: 71 (CW 50, SSB 21)
5760MHz: 31 (CW 31, SSB 6, CW/SSB)
Non-EME QSOs: 11,500 on HF/VHF/UHF Satellite
by local amateurs.
Project BIG-DISH Board Members:
JH1KRC, JM1GSH, 7M2PDT, JA1BGU, JA5FNX,
JE1KFX, JF1AKD, JH1EFA, JH6RTO, JJINNd,
and JROXHL
Associate members:
JAOGPT, JAOTJU, JAIBAX, JA5NNS, JA6EET,
JATAGL, JEODKR, JE1BNZ, JE1JKL, JHOMHE,
JH1INOT, JH1TVZ, JH1XUJ, JH2COZ, JH5FOQ,
JH7SIA, JKIKTY, JOILDY, JO7TMJS, JP1INWZ,
JQ2LVT, and JRIPJH
Advisors:
7K8LGC, JA2TY, JA3MKS, JA3SGR, JA4BLC,
JA6AHB, JA6CZD, JA6XKQ, JA7JJN, JA9BOH,
JF3HUC, JS3SIM, JG2BRI, JHOWJF, JH1WLK,
JH3EAO, JH3ERQ, JH5AKH, JJ3JHP, JR3JLL,
CT1DMK, K2UYH, LA8LF, OM6AA, OMIATT,
and P. Hazdra
QSL Manager:
JH6RTO/1: Seiji Fukushima, Bellflower 2506,
1182 Hase, Atsugi, Kanagawa 243-0036, Japan
_ Go to:
Yuki JH1INBN and other stuffs of KDDI
Corporation, the stuffs of Japan Amateur Radio
League, and the dedicated officals of the Bureau of
Telecommunications, and Ministry of Internal
Affairs.
The Project BIG-DISH 2008, 8N1IEME
http://8nleme.jp
Japan Amateur Radio League
http://www.jarl.or.jp/
IBA-4 antenna is now rebuilt to be a
radio-telescope for VLBI research.