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Helge SM/LA6NCA Activates Colorburst Liberation Army in Sweden!
KE5HPY Builds a QRP Transmitter
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Thought you would appreciate a recent project inspired by the fabulous EMRFD.Β This started as a test bed W7ZOI universal tx to evaluate my stock of RF BJTs and employ some FT-243s in the shack.Β That was interesting by itself but the 16-32 dBm output (choice of device really matters!) did not reach the intended targets using my 40m dipole.Β So, add a W7EL RF PA and a nifty, clean 7W emerges after damping output from Q2.Β The final is pleasantly efficient and needs only a modest heatsink to survive key down for 60 seconds.Β KFS then reported S7-9.Β Success.Β Time to box it up and go XTO, add a meter output at 30dB down and an RF driven LED indicator.Β Left room to add an ATtiny85 CQ keyer but ran out of time.Β Had to move house and knock down my 40-6m antennas.Β That was the most painful part of moving.Β So this rig sits while I find a new place to hang antennas.Β Eventually, the TX will get a RX mate when it is possible to box up a 40m DC RX with Si5751 and OLED display. Am still trying to solve how to mount an OLED display cleanly in an aluminum box. First, I have to reconstruct my workbench.
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Keep up your good work, and that is no April Foolβs joke.Β
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73,
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Chuck KE5HPY
Deep Space Station 43 -- Canberra, Australia
DSS-43 boasts a pointing accuracy of 0.005 degrees (18 arc seconds)βwhich is important for ensuring that it is pointed directly at the receiver on a distant spacecraft. Voyager 2 broadcasts using a 23-watt radio. But by the time the signals traverse the multibillion-kilometer distance from the heliopause to Earth, their power has faded to a level 20 billion times weaker than what is needed to run a digital watch. Capturing every bit of the incident signals is crucial to gathering useful information from the transmissions.
The antenna has a transmitter capable of 400 kilowatts, with a beam width of 0.0038 degrees. Without the 1987 upgrade, signals sent from DSS-43 to a spacecraft venturing outside the solar system likely never would reach their target.