K1WHS / W4DEX 10 GHz, 5760 MHz, 3456 MHz and 2304 MHz Contacts

25 September 2004

 

This is a summary of weather, propagation and events leading up to and during these contacts and a brief description of the equipment used.

During the few days prior to 25 September 04 there was a slow moving high pressure air mass over the mid west.  The Eastern North America Hepburn Tropo Index maps indicated good conditions in various places west of the Appalachian Mountains.  Also good propagation reports were being posted on the DX World UHF Activity Logger page. 

On Friday the 23rd of September the high pressure ridge had moved to the east of the mountains.  Also hurricane Jeanne was wandering around off the eastern coast of Florida.  VHF and UHF conditions were enhanced from North Carolina to the North East but signals were not near as strong as the September 2001 tropo event.

During the Friday evening hours there were a few stations on but again signals were not extremely strong.  I could not hear any of the W3CCX Beacons.  The Hepburn map for Saturday 1200 Z  indicated a hot spot over Maryland possibly indicating good conditions for Saturday morning. 

About midnight Friday I figured I would get to bed and get up early thinking that on Saturday there would be more operators on.  I had my hand on the station power switch just as I heard Dave,  K1WHS on 144.200.  N4HN in nearby Charlotte was working Dave.  Dave's signal was very good but not as strong as I have heard him many times before.  Dave said he was going to get up early and was about to close down for the night.  I thought he was going to get up early to catch the morning enhancement.  N4HN and Dave moved to 432 MHz.  Dave's signal was  stronger on 432 MHz but still down from many openings prior.  I made my presence known mainly to tell Dave I would be on by sunrise.  But first I asked jokingly if he would like to try 10 GHz.  Dave said he had the gear hot and would give me a signal.   His 10 GHz signal was Q5 and I didn't even have to touch the dial!  We kicked it back and forth several times and I logged the contact at 0415 Z as a very conservative 539.   The signal had some QSB but it never went into the noise and peaked about 559. 

After we regained our composure Dave said we should try 5.7 GHz.  I found his signal about the same strength and we easily completed the contact at 0427 Z.  The 5.7 GHz path probably was stronger but I only have a small homebrew horn antenna which has maybe 20 db gain on this band compared to 30+ db gain on 10 GHz with the 2 foot dish.  Moving on down the bands we completed easily on 3.4 GHz at 0432 Z and on 2.3 GHz at 0438 Z.  Dave's signal on these bands were also in the 559 range. 

While discussing our long awaited success I realized I had not recorded the contacts as I had planed to do.  One half hour after our 10 GHz contact I asked Dave to put his signal back on so I could record a .wav file.  During about the next 15 minutes not a trace of his signal was heard!  We then realized how lucky we were to have caught the opening when we did. 

Another stroke of luck was that I called Dave in the first place.  His signal wasn't very strong on 144 MHz and I figured he would be on Saturday morning.  When he told me he would have something to talk about on his way to a hamfest in the morning I realized how close we came to missing a chance to even try the path at sunrise.

I went to bed around  2 a.m. thinking I would probably sleep through the good  morning conditions just after sunrise.  However at 6 a.m. I was wide awake and ready for more DX.  By 7 a.m. the W3CCX Beacons up through 3456 MHz were coming in very well.  At 8 a.m. the 3456 MHz beacon was the strongest I have ever seen it!  The only problem was that I could not find anyone to run microwave with.  I suspect most everyone had other plans for a beautiful fall Saturday morning.  I did run across K1RZ at 9 a.m. and we tried 10 GHz with no luck.  By this time the W3CCX 3456 MHz beacon's signal was gone.  The 432 MHz beacon was Q5 up until about mid day.


Below is map showing the path between K1WHS and W4DEX.  Note that except for a few miles over the Chesapeake Bay area the path is over land.  My location is about 135 miles from the nearest coastline which is the Myrtle Beach, SC area.  The coast is over 200 miles to due east.  Dave is over 20 miles inland.


Below is the surface weather map for 25 September 2004.  Note the high pressure ridge along the path and the moisture pump, Jeanne, off the coast for Florida.


K1WHS, Dave Olean, Lebanon, Maine - Location, Microwave Gear and QSO Report:
My shack is located about 2200 feet behind my house, on the top of a
rocky ridge in Southwestern Maine. The elevation is about 870 feet at ground
level.  (Lat Lon= N43 degr 24.702', West 70 degr. 57.638') The 10 GHz
antenna is side mounted on a Rohn 55 tower at the 115 ft level. The tower
has star guying, and the 10 GHz mast has been plumbed so that the dish is
pointing at the horizon. The entire system is mounted behind a 36" dish
(DEMI) with my own single band feed. (Directive Systems) So the 10 Ghz
antenna is just below 1000 ft asl.  My shot towards your (W4DEX) direction (225
degrees)  is fairly good. I run into the edge of a 1420 ft hill that is
about 16 miles away. South of 225 degrees, my horizon gets really good with
negative horizon angles from 220 degrees thru  180 and over to about 90
degrees (East) There are no trees in front of the dish here. My immediate
area is pretty clear tree wise. Most are about 30 ft high, so the dish is
way above them. At 225 degrees, the entire path is all over land between our
two QTHs. The only water in that path is Chesapeake Bay near Baltimore.

The 10 GHz rig consists of a DEM transverter with a 21 watt output power
FET amplifier. There is a 1 dB NF preamp in the RX line. I use a Prosistel
small rotor on 10 Ghz.  The 144 MHz IF runs down the tower thru 3/8" heliax.
We use the heliax for added shielding of the IF. This station also doubles
as a multi op station, so we don't want the 144 MHz kilowatt overloading the
10 GHz IF! I have an Elecraft K2 as the two meter IF rig. We added a
Downeast Microwave 144 transverter inside the K2, so it functions as a stand
alone two meter rig and has great filtering for CW reception.  I use three
K2s for all the microwave bands.

The shack is located quite far from any power lines, so I must make my
own electricity up there. I have a shed which houses a 30 KW 3 phase diesel
generator which supplies all the power for a multi op station with all the
kilowatts running at once. Throw in a few air conditioners and electric
baseboard heat for cooler wx, and I am glad to have the reserve power
available. The downside is that the darn thing gulps diesel fuel at 1.7
gallons per hour!

When we worked, I had been running the 10 GHz rig since 8:30PM  and had
yet to run a sked with anyone until you called. I think I ran one sked on
2304, but none higher. Needless to say, I was thrilled when you called in on
432. I was just sitting here waiting to exercise those microwave bands. The
rig was all warmed up and waiting! After all the failed attempts between us
over the last three years, when you called on 432 and said you were hearing
dashes, I went into some crazy state. I honestly felt like it was a dream
and that I was about to wake up. When I signed my calls and sent my grid, I
was fully expecting to hear nothing but noise on receive. When I heard you
calling me and being 2 or 3 S units out of the noise, you could have knocked
me over with a feather. Really you were that loud and  I was sure you would
copy my SSB. I tried it, but I guess it did not come through too well. There
was some QSB I guess. I never missed a dit in your CW transmissions on this
end. When it was all over, I had to pinch myself to make sure I was not
dreaming. Then I got really excited! I still had no idea that it was any
kind of a record. Only when you told me was I aware of that. I was just so
happy to get a chance to work some good DX on 10 GHz. I have been harping
for years that we need more home activity so that we can catch these events.
I was sure that I would be able to work down to Norfolk, VA and maybe the
outer banks on a regular basis maybe once or twice a season. I did work
W3IY/R  in FM26 back in 2001, but the problem is that, with no home
activity, many good nights go by un utilized. Here in New England there are
a few home stations. W1FKF, W1GHZ,  K1GX, K1TEO come to mind. AF1T has a
system that he points out his window, so I guess he is a home station too.
In the NYC area, we have K2TXB, W2KV, K2UYH, and AA2UK. Most summer nights
when things are quiet, with little wind, I can work K2TXB and AA2UK. I could
also work Al, K2UYH, but lately he is having waveguide problems.  More home
stations in the right spots will make this distance record disappear in
rapid order. I do not live in an area that is blessed with great tropo.
Chances are that there are many better paths than this one! I would think
that a good 10 GHz station on Cape Cod, or Long Island, NY,  will have a
good chance to work Florida on 10 GHz.

    Other microwave data for K1WHS:

5760:  20 watts rf at the dish. <1 dB NF preamp and DEM transverter
bolted to the back of the 36" dish at about 110 ft above ground. K2 IF
radio.  The 5760 QSO is also an overland DX record too.

3456:  42 watts rf at the antenna consisting of 4 X 112 element
Blowtorch loop yagis at 137 ft.  The rig is tower mounted just below the
3456 frame. This array is as sharp as a 2 ft dish on 10 GHz!  DEM
transverter,  K2 IF radio.

2304: 100 watts in shack to 130 ft of 1 5/8" Heliax. Preamp is tower
mounted at the antenna. K2 used as the IF with a DEM transverter.  I am
figuring about 70 watts gets to the antenna. Antenna is 4 X 76 el Blowtorch
loop yagis at 128 ft.

1296: 150 watts 2X 7289 air cooled amp with 130 ft 1 5/8" coax, tower
mtd preamp,  4 X 45 el loop yagis at 133 ft. Swedish transverter (old!) and
a K2 IF radio.

903:   200 watts in shack, 130 ft 1 5/8" Heliax, DEM xverter, preamp at
antenna. 4 X 33 el loop yagis at 124 ft.  K2 IF.

73
Dave K1WHS
K1WHS Antennas:

Here is a close up picture of the microwave tower. The loopers are
arranged with 3456 on the top, followed by 1296, 2304, and 903 on the
bottom.  The 10 GHz dish is the top one. The 24 GHz system is missing from
this photo. 5 GHz is the lowest dish.
 

W4DEX, Dexter McIntyre, Stanfield, North Carolina
Location:   My QTH is about 27 miles due east of downtown Charlotte, NC.
The nearest coast line is about 135 miles to the SE which is the Myrtle Beach, 
SC area.  The coast line is over 200 miles to the east.
 

10 GHz:   The antenna is a 24 inch diameter "Kruth Special" fed with a section of WR-90 flex connected to EW90 pressurized elliptical waveguide.  The transverter is made from SSB Electronics boxes which were assembled by W4OJK (sk).   A modified Ku band LNB is used for the LNA.  Power output is courtesy of a Hughes TWT capable of a little over 20 watts.  T/R switching is done with a waveguide relay.

 

5760 MHz:   The antenna at 105 feet is a homebrew 20 db horn made from sheet copper which can be seen in the picture below.  It just above the 2 foot 10 GHz dish.  A short section of Superflex around the rotor connects the antenna to pressurized elliptical waveguide.  The transverter is a collection of surplus items, a DR-6 preamp for the front end and an Aventek 10 watt power amp for the output.

 

3456 MHz:   The antenna is a loop yagi. (just above the 5.7 GHz horn)  Coax is 7/8" Heliax.  The transverter is a combination of surplus items, a TVRO LNA, California Microwave LO and Western Electric power amps.  Output power is 7 watts.

 

2304 MHz:   The antenna here is another 45 element loop Yagi (just below the 1296 MHz antenna) Coax is 7/8" Heliax.  The transverter is based on a Jim Davey, WA8NLC, "no tune transverter" board and uses surplus Farinon amplifier boards.  Power output is 5 watts.

 

W4DEX Antennas:

 

 

The 5760 MHz Horn that made this contact :)  "The Little Horn That Could"

 

 

Of course the real work was done on the other end by Dave's antenna.  This proves you do not have to put up a big microwave antenna to get results. 


 

Path Distance Calculation

 

K1WHS:    43.4117     N    70.9606 W

W4DEX:    35.256166 N    80.3800 W

 

Range and bearing program BD_2004 available at the W1GHZ page, calculates this path to be:

 

754.760 miles / 1214.699 km

 

This was a new North American Continental DX record on 5.7 and 10 GHz for close to 8 years.

 

(New record set by W5LUA EM13qc - KVXM EL98pj,  998.357 miles / 1,606.63 km on 4th of June, 2012)

 

http://www.arrl.org/qst/worldabove/dxrecords.html

http://www.ntms.org/DXRecords.htm

 


 

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