delara news Delaware Amateur Radio Association, Delaware OH   VOL 36 NUMBER 8

Dr. Bob

Bob Dixon, W8ERD

MESH at the Ironman

AT HEADQUARTERS Things started out badly.  Craig W8CR was to pick me up at 5:45 am.  I set the alarm clock in my cell phone for 5 am.  Amazingly I woke up at 5:36 and realized the alarm had failed to go off.  So in 9 minutes (with my wife’s help) I was able to dash around and get ready to go just in time for Craig’s arrival. But no breakfast, forgot wallet and name tag.   Fortunately I had packed all the equipment up the night before, so Craig was able to load it quickly. My mental acuity was not all it could be. We arrived at Meek Aquatic Center and with help from our folks already there, everything was carried in. During the setup the day before, we located the best (darkest) place for the projection screen to be located, in the big  main room at Meek.  We discovered that the Powers That Be decided to move the screen so they could see it more easily from their table locations.  Unfortunately that placed it so the sun shined directly on the screen, and the room is very bright with big windows all around, and also second floor windows shining down.  So the screen  was all washed out and it was difficult to see the remote mesh video we were showing on it. (see picture) We had also discovered the previous day that the projector provided to us by the Meek staff was not very bright, and it had low resolution.  Fortunately I brought my own better projector “just in case”, and we used that.  It was mounted ingeniously on 3 styrofoam cups to get the best angle (see picture). The crew installed the mesh access point on the roof, and Craig was forever memorialized by the picture shown in the Delaware Gazette, holding the antenna mast very heroically.   The link to the EOC tower worked perfectly.  Another crew installed the 2 meter antenna out on the lawn. Both cables were run thru the door, held open with a chair. The 2M signals were great, as we could hear the Marion repeater.  So we made a test transmission with the radio Donn K8AOK brought, only to learn that our audio was 100% hum.  Hmmmm. Fortunately again I had brought my own 2M radio and power supply “just in case”, so we swapped power supples and it worked perfectly. The big meeting room is very live acoustically, so it was very noisy and we could hardly hear our  radio. Many people were talking loudly, and there were other radios in operation.  If we turned our radio up louder, they told us to turn it down.  So Donn made a custom audio director from a Styrofoam cup that directed our audio towards  us and it worked much better (see picture). NOTE - Next year we must have a headset for the operator, but it cannot also turn off the room audio.  Somebody please make that happen. AT THE BEACH Paul KD8UUA, Larry AC8YE and Ben W8AXE erected their camera station with a big dish pointed across the lake towards our relay station.    Tim K8TAT and Grant KD8UNQ erected the relay station on the levee. We have had trouble with this link before. In the middle of the previous night, I realized that we could improve things by having Tim use the other big dish pointing towards the beach (instead of the omni as planned), and then using the smaller dish loaned by Ken W8RUT to point towards the Delaware 911 tower.  That would also provide greater separation between the two antennas to reduce mutual interference.  But Tim did not have another mast, so Craig took off in his car to bring him a mast and to help with the installation.  He reports that driving on the levee is very treacherous, as it is narrow, and one false move could land you either in the lake or on busy Route 23. They got it all set up and that NAILED the link across the lake. So that worked well.   But the link south to the Delaware tower was still marginal with about 20dB SNR.  Higher antennas would help, but they are already as high as it is safe with portable antenna masts. Meek is 5 relay hops away from the beach, much more than we have ever done before, and it just did not work well. Stan N8BHL at Red Cross was able to get a marginal picture, as he is fewer hops away.  Craig and Tim are talking about using a balloon next year to get the mesh node several hundred feet in the air, which would very likely fix this problem.  I can make a lightweight antenna and cable. IN THE TOWN We planned to have 3 stations along William street at various locations, as requested by the Delaware Police Department.  Mike KD8YED set his station up at Henry St, and it worked perfectly all day. I did a trace route, and found that he was connecting directly to Meek, not going thru the EOC 911 tower as we had planned, which probably helped by eliminating an extra relay point.  Very strangely, while watching his video, on 3 occasions I saw a shadow cross the street in the crosswalk, without any accompanying person.  Wish that had been recorded. Unfortunately our other two stations got stuck in traffic trying to get out of the beach to get to these new locations, so they were late in arriving.  NOTE - We have to plan that  better next year.   Larry AC8YE got his station set up, but the signal was marginal and all we got was a still picture  at Meek. This is odd, since that worked fine last year.  I figured out why.  Last year we used a big dish at the downtown locations, whereas this year we used the more portable omni antennas.  This was my mistake. NOTE - Use big dishes and masts downtown next year, even if it seems like overkill. I also tried lowering the resolution and frame rate of the cameras, but it made no difference. AC8YE PC battery died, so he could not make adjustments at his end. KD8UUA was never able to get his station working at the 3rd location, for reasons unknown. I am sure there is more info and pictures to be had from others who were in the field.
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