Ham Radio Eme Antenna Moon Reflection
.432 MHz EME low noise amplifier. Circuit, components and image by Christoph Petermann DF9CY.Argo is a freeware windows viewer for MTHELL, Slow CW, like QRSS and DFCW.
Antenna Party: A ham radio tradition in which hams gather to assist in the erection of antennas or towers. Earth-Moon-Earth communication, in which signals are reflected off the moon back to earth; “Moon bounce”. Radio signal propagation by reflection from short-lived ionization trails of meteors in the atmosphere. Earth-Moon-Earth, EME or Moonbounce propagation is a really challenging, but interesting form of radio propagation for radio amateurs to use. Moonbounce propagation presents a number of significant technical and operating challenges, but in this is provides a real sense of achievement and enjoyment when a contact has been successfully achieved. HAM radios use the antennas to send signals called Earth Moon Earth (EME). The EME signal, or moon bounce, is a communications technique that sends radio waves from an Earth-based transmitter.
DK3QN - Hints for EME DK3QN's Ham Radio MenuAntennasSome hints for Newcomers to Earth-Moon-Earth communication on 144 MHzIntroduction:We've been QRV now on 2m EME since almost one year (started end of May 2009).The following summarizes some basic findings from that one year of EME activityon the 2m Ham Radio band.This all is related to a minimum 2m EME set-up which we consider to be requiredin order to perform 2m EME QSOs on a regular base.Findings:Mode:The by far most used and most reliable mode of operation is JT65B, due to the readabilityof signals with respect to noise. The decoding is done with the 'help' of a software programrunning on a PC ('WSJT' developed by K1JT). 'WSJT' is Freeware and can be downloadedfrom the Internet.I'd dare to say that 95% of all EME QSO's on 2m are performed in JT65B mode (not takinginto account EME contest situations etc.).From our experience, JT65B still decodes signals which are some 25 to 28 db belowthe noise. This is about 10 db better compared to what the human ear may be able to copyas a signal (CW signal, i.e.), when filtered appropriately (narrow bandwidth).In order to participate in 2m EME communication, you absolutely need to enable yourequipment to run JT65B flawlessly (no audio 'hum', appropraiate sequencing onRX/TX change-over, etc.).Transceiver hints:Saying that, you need to double-check that your transceiver (i.e. TX (and RX) part of it)sends-out the various JT65B tones at about equal output levels.
Ham Radio Eme Antenna Moon Reflection Schedule
Ham Radio Eme Antenna Moon Reflection Chart
We've seen one transceiverwhere the sent-out tones varied in RF output power a lot, most likely due to the rippleof the incorporated SSB filter, causing problems at the receiver side ('bad reads' or'no decodes' even if our signal was 'good enough' off the moon).So, watch out for this. The output power should not change for much more than 10 percentrelated to the various JT65B tones sent out.Antenna(s), etc.:In order to perform 2m EME QSOs on a regular base and given the fact that you aremost likely.not. a 'rare bird (call sign)', who is being called anyway by strong stationsany time and any frequency, you need to provide a minimum of 15 dbd of antenna gainon 2m.This amount of gain can be achieved e.g. By two horizontally stacked yagis withabout 4 to 5 meters of boom length. A single Yagi would require a boom length of about10m in order to achieve about 15 dbd of gain.VE7BQH provides a table in the Internet where performance data of various 2m antennascan be looked up as a reference. Based on this data we selected the I0JXX 8-elementYagi as it has a pretty good price-performance ratio for a 4.1m long antenna (12.1 dbd ofgain for a single Yagi). There are many other choices, though.