ARRL 10GHz And Up - Part 1 as seen by Herbert AF4JF

The SLAMS group has once again attended the "ARRL 10GHz And Up" Contest during the weekend of August 21 and 22. We have split the activities between the two days of the contest - first day was just moving around our area, second started with a 90 miles road trip to Hannibal, MO.

The first day was mostly to test our modified equipment. Harry WA0CNS started at High Ridge EM48rl while Herbert was at Community College EM48qs. Fast QSO over 33km.

AF4JF at Community College aiming South

Ron KO0Z joined Herbert (and brought a breakfast) at the CC park while Harry was driving to our next stop, which was the Lakeside 370 park in EM48rt. Harry and Herbert made a QSO on 10GHz, 24GHz and 122GHz from there.

Lakeside 370 Park

Next stop was the Iffrig Road in EM48qt. Harry and Herbert worked Zack W9SZ from EN50ue over 250km over Rain Scatter from that location. Also tried to work Gedas W8BYA, but no success this time. Sorry, I forgot to take some pictures.

The day was very hot, so we gave up at this time and went home to get ready for "tomorrow".

On Sunday, the day after, we got out of beds quite early and met at the commuter parking lot in St. Peters at 5:00am. The topic of the day was a road trip to Hannibal, MO (yes, that's the Mark Twain town with caves and the Tom/Huckleberry/Becky kids). We have arrived there in the "Lover's Leap Park" at 7:00am, just in time for first QSO with Jon W0ZQ and Gary WB0LJC in EM42bn, about 322km away!

Harry WA0CNS in EM49hq Hannibal MO

Herbert AF4JF set up for 10GHz in EM49hq

View across Mississippi River in Hannibal, MO

Herbert and Harry also made a 122GHz QSO across 5 km from the hill to a parking lot in downtown near the river in EM49hr where Harry set up before we left Hannibal and went to Louisiana, MO.

We arrived in Louisiana in EM49lk just on time to catch Zack W9SZ and John K9JK at Ohlman Cemetery in EM59ji about 152km away. We have made some QSOs and continued our journey by returning to the Community College in EM49qs while Zack and John moved closer to Saint Louis.

Harry WA0CNS in EM49lk

Herbert's dog Darcey in EM49lk

We have returned to EM49qs from there. Zack went to Dow, EM49ua and John to Gillespie EM58ax to make another QSO with us. John joined Zack in EM49ua again to make another QSO with us. These were 62 and 40km.

Both teams were quite tired after all this, but we have decided on one more move - John and Zack went to Eagles Roost in Pere Marquette State Park, EM48rx. They both made a final QSO with Herbert over the path of 24km and we have called a day. The Saint Louis team was home in several minutes, but John and Zack spent most of the evening driving back home. Thanks guys for coming here and playing with us!

122 GHz again

Harry WA0CNS and Herbert AF4JF succeeded in extending the distance covered by QSO on 122GHz to 7.671 km (4.76 mile) today. Harry was at new SLAMS location on Iffrig Road in St Peters, MO (EM48qt74cu) while Herbert went across Mississippi River to the Winneberg Road on a hill near Brussels, IL (EM48qv90rv). Two-way CW QSO on 122GHz was completed at 10:59am today (December 14, 2020). This is not only our longest QSO on 122GHz so far, but it also seems to be the very first QSO between Missouri and Illinois on 122GHz ever.

Herbert and Harry met at the Iffrig Road first. Harry started setting up while Herbert went to Golden Eagle Ferry about 3 miles away. That ferry operates every day and has quite short waiting time. At least usually. Mr. Murphy has not overslept today, so Herbert's crossing on the ferry was delayed by a huge commercial barge crossing the path. It took over 15 minutes until that huge thing disappeared.

There is a hill just across the river. It is not that high (590 feet a.s.l.), but still high enough to block the line of sight to everything on the Illinois side. Harry and Herbert actually tried much longer distance (over 25km) on December 4, but this hill protruded into the Fresnel zones between our intended locations. Luckily Harry WA0CNS, Herbert AF4JF and Ron KO0Z have done their homework this time and identified the location on Winneberg Road prior to this test today. Looks like we will use these two locations for future tests.

The atmospheric conditions were not all that great today. Sure, it stopped raining and fog went away this morning, but the relative humidity was still too high:

• temperature 3.6 deg. C

• dew point -5.2 deg. C

• pressure 1005.2 mBar

• humidity 51.1 %

• wind speed 2.4 m/s

Signal from Harry was S9 with QSB to S5. Herbert's signal was much weaker on Harry's side (Herbert uses a 21 dB horn antenna while Harry has a dish):

Herbert's AF4JF view towards Harry

Harry's WA0CNS view towards Herbert

Waiting for the ferry to return back to Missouri

Goal for today was met. However, we are still at the begin, many more miles to cross on 122GHz. Looks like this was probably close to the limit for a station with small horn antenna. We will try the same path with dishes on both sides next. Some other day.

Success on 122 GHz

Harry WA0CNS and Herbert AF4JF met together for another round of testing our new 122GHz units from VK. Ron KO0Z has been in some activity with his grand children and supported us on the phone.

We have decided to repeat the test from October 25 (2020) when Harry went to SSM facility in EM48rq and Herbert found a nice parking lot on Katy Trail in EM48rr. We didn't make that QSO on October 20. There is a direct line of sight between both locations, so we tried again using rifle scopes to aim our antennas today. Following pictures show Herbert's side of the path on Greens Bottom Road in EM48rr:

Thanks to using powerful binoculars, Harry spotted Herbert's car arriving at the parking lot and knew exactly where to aim the antenna. We have made our CW QSO at 08:43 am with signal strength S5-9 on both sides. The distance, according to Google Earth, was 3.26 mile (5.25 km):

Weather info taken in EM48rr at 08:30 am CST:

• temperature 22.8 deg. C
• dew point 9.3 deg. C
• pressure 1010.2 mBar
• humidity 43.1 %
• no wind

This was first part of our plans for the day. The second part was moving to the town of Defiance, MO to our "backup location" along the Katy Trail. Harry stopped close to Defiance in EM48op and Herbert went a little further to Matson in EM48oo. The distance between these points is, according to Google Earth, 1.74 mile (2.80 km):

Weather info taken in EM48oo at 10:39 am CST:

• temperature 26.8 deg. C
• dew point 12.2 deg. C
• pressure 1008.7 mBar
• humidity 38.9 %
• wind 2.2 km/h ( 2 feet / sec)

This location, despite the shorter distance, turned out to be more difficult due to a problem with direct line of sight - rifle scope on Herbert's side revealed that he was pointing at wrong location and had to move a little to see the correct one. After moving the station, QSO was made at 10:49 am CST wit the same strength as the first QSO (S5-9 QSB). However, thanks to the blowing wind, the frequency was a little unstable. We definitely need to pay more attention to thermal insulation of the 122GHz board to prevent wind from changing frequency through making temperature changes. Both stations were using GPS reference 1 pps, which seems to be too slow. We need to modify our stations for 10MHz reference signal disciplined by GPS.

Picture shows the "Judgement Tree" memorial park in Matson, EM48oo where Herbert was located:

Herbert is only using a 19dBi conical horn for antenna. Harry's station has a 13 inch dish antenna:

This was our last attempt for QSO for the day. Next topic on our plan was the SLAMS/BARS planning meeting at the Chandler Hill winery. We usually do not eat inside any facility these days, but this winery is offering outdoor seating and online ordering of food and drinks. Here is how the seating looked like (and Yes, this facility allows dogs even inside):

Everything considered, a very successful day! We have pushed our 122GHz record up to 5.25 km. Our next attempt, hopefully this year, will be to get it over 10 km. Watch for new posting soon!

122GHz challenge

When Harry WA0CNS and Herbert AF4JF made their first 122GHz QSO on September 20, 2020 during second leg of the ARRL microwave contest, everybody was surprised how easy it was. Our second 122GHz QSO during the SPRINT Contest on October 12 made it look even easier. We were planning on extending the distance spanned by our QSOs over 10 miles. First step was supposed to be a QSO from EM48rq (Chesterfield, MO) to EM48rr (Harvester, MO) across the Missouri river over a distance of 3.65 km with direct line of sight. We have found suitable locations, checked them ahead of time ... everything seemed to be "granted":

This picture shows Herbert's location and open view towards Harry (on a hill on the horizon):

However, neither of us heard a beep, just a noise. We have tried to turn our antennas, tune the radios up- and down, move around the parking lot ... nothing. Herbert even went across the river to Harry's location to make sure that Harry really points his antenna in correct direction. Everything was OK, just no signal. 

Weather situation (recorded on Herbert's side of the river) was:

• temperature 4.1 deg. C
• dew point 1.3 deg. C
• pressure 1011.9 mBar
• humidity 43.2 %

The day was actually very windy, we were both "frozen to the bone", so we gave up for the day and decided to continue on the next day, make sure our stations still work and decide how to continue.

Next day was a little warmer. It was also the day of a SLAMS meeting. The SLAMS just started having meetings in the local park instead of eating breakfast together at Denny's. Harry WA0CNS and Herbert AF4JF got together in the Creve Coeur park. (EM48sr). Armand KD0PXF joined us for a short talk later. Harry started a small fire to keep our fingers movable:

Weather situation was:

• temperature 16.3 deg. C
• dew point 3.9 deg. C
• pressure 1000.5 mBar
• humidity 40.2 %

We have set up our stations approximately 100 ft. apart first, then about 1000 ft. In both cases, we have heard each other immediately. Signals were very strong and stable, exactly on the frequency (IF on 144.4 MHz CW) where expected:

WA0CNS

AF4JF

View from AF4JF towards WA0CNS

Well, our stations appear to be in good shape. Signals were very strong and aiming was not too critical (at least not for Herbert who uses a conical horn). We are not sure why our contact across the distance of 3.65 km didn't work. Looks like QSOs on the 122GHz band will be a challenge and come with surprises...

Herbert and Harry already decided on next try, two weeks ahead from now. We hope to have more good news to report after that next test.

73 Herbert

AF4JF

New 122GHz Station

Do you want to become QRV on 122GHz? You can buy a kit that uses a chip that does most of the work (click here).

It seems to be doable and not too expensive!

73 Herbert

AF4JF