Very first two-way 3.4 GHz troposcatter QSO between Estonia and Finland:
- OM Viljo, ES5PC had heard from SM0DFP about our SM-OH 3400 MHz QSO some time earlier and contacted me about a sked
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We agreed a sked for the same evening, Friday, August 20th - I would be QRV from Sappee, KP21GJ
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I had hardly unpacked my equipment from the previous QSO with OM Per, SM0DFP and I swapped the 90 cm dish for my usual 120 cm dish
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getting to the site just before sunset allowed me to calibrate my dish pointing using the setting sun
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alignment by the feed shadow is reasonably accurate, but using the actual solar thermal noise would be more accurate
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unfortunately the sun was already too low on the horizon (actually 0.53 degrees at 2100 local time)
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and as luck would have it, around 2100 local time the moon is exactly in line with ES5PC in KO38HJ, serving as a second calibration ;-)
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the QRB between KP21GJ, Sappee and KO38HJ, ES5PC works out at 353 km, 160 degrees from Sappee
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this beats the current tropo distance record from 29.08.2000 when I used the same equipment to work OH3TR from OH2Z at 251 km QRB
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my calculations are based on Roger Hedin's GCM software, calculating from Maidenhead grid square center to center
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OH2DG has worked ES5PC previously this summer on Earth Moon Earth (EME) - their troposcatter QRB would have been 228 km
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here is a nice view of the full setup, waiting for the establishment of contact between Estonia and Finland
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and yet another photo of the French Coffee can feeding my dishes on 3.4 GHz :-)
- here you may find a video clip of ES5PC (5 Mb) on SSB at the beginning of the QSO - signals improved slightly later on into the 353 km QSO
- signals from ES5PC actually improved quite a bit about an hour later as you can hear in this video (3 Mb) of Viljo's CW
- fortunately also Per, SM0DFP was at home that evening, so we had a nice SSB QSO (5.6 Mb) with him too (344 km between JP90JC and KP21GJ)
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equipment at ES5PC: 4.5 m dish, 80 W, 0.8 dB noise figure, obstructions
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equipment at OH2AUE/P: 1.2 m dish, 7 W, cold sky/ground noise 2.45 dB, few pinetree tops at 100 m distance
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here is a compressed WAV file (660k) I extracted from OM Viljo's SDR-IQ recording of my signal (the drift is the personality of my transverter)
Created 25.08.2010 and latest update 14.01.2019/OH2AUE
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