EME Operation (Moonbounce)


EME operation, also known as moonbounce, is a technique used by amateur radio operators to communicate with other operators around the world using the moon as a reflector. The process involves transmitting a signal from an antenna on Earth to the moon, where it is reflected back to another antenna on Earth.

This technique requires specialized equipment, including high power transmitters, large antennas, and sensitive receivers. The antennas used for EME operation are typically directional, with high gain, which allows for a stronger signal to be transmitted and received.

EME operation is a challenging form of communication that requires a significant amount of skill and knowledge. The success of an EME contact depends on several factors, including the quality of the equipment, the frequency and power of the signal, and the atmospheric conditions.

Despite the challenges, EME operation is a popular activity among amateur radio operators. It provides a unique opportunity to communicate with other operators around the world using a technique that is both challenging and rewarding.

In conclusion, EME operation, or moonbounce, is a specialized technique used by amateur radio operators to communicate with other operators around the world. It requires specialized equipment and a significant amount of skill and knowledge, but it provides a unique and rewarding experience for those who practice it.

As of today, March 2023, RHR has installed 2M EME capability at the W2/Jefferson station. This station has a moderate sized antenna array that consists of four 16 Element long boom yagi’s computer optimized for extreme weak signals in the 144.100-144.300mhz segment. Feeding this array is a high quality high gain, low noise antenna mounted preamplifier with built in band pass filter. We drive this array with a 1KW SSPA amplifier which is driven by a FlexRadio 6600 series radio.

What is possible with that array?

  • EME - Moon Bounce - Work DXCC on 2m! yes, this is very possible with this array. Under good conditions you should also be able to hear your own echoes!!!
  • FT8 - Using the built in RHR FT8 technology you can work great terrestrial DX on 2m!
  • There is a surprising amount of activity on terrestrial 2M. You can start with the morning around 144.205mhz.
  • Check propagation with the great selections of beacons.
  • Need another new challenge, you can start chasing VUCC on 2m using this array.

What do I need to work EME on RHR?

  • RHR Desktop App (Windows and Mac)
  • SmartSDR (Windows only, not needed on Mac) (Whatever version we are running on RHR at the time)
  • WSJT-X Version 2.5.1 or newer.
  • Patience!

If you are on a Mac, check out this user created article.     Setup a Mac for EME operation on RHR

Let’s start with a few videos I made to show working some contacts on the moon, There is a mixture here. I would recommend watching them, each I touch on different points that are important. This article is a work in progress, so I will continue to update it with more detailed info.

Now that you have seen some EME activity in action you can start getting things wired up and making contacts on the moon. The easiest way to think of of this like this, the setup is EXACTLY the same as running WSJT-X locally on your PC. You are simply changing the mode from FT8 or FT4 to Q65 or JT65 depending on what mode you want to operate with. Thats really it! Yes, there are some new ropes on how EME contacts are made with those modes but you will pick them up quickly.

So if you have not setup WSJT-X locally before then I suggest that you check out this knowledge base article where I go over the steps on setting that up. Then you can apply what you have seen in the above videos for moon operation.

KB Article on setting up WSJT-X with SmartSDR

Useful tools/websites for working EME DX

  • LiveCQ.eu - Great for seeing real-time spots off the moon. (Spots only show up when users skimmer running and posting to the site) You will see a lot of activity during good moon conditions.
  • Moon Conditions - This is important, this site has a nice graph for each month’s moon conditions. MMMonVHF.de Basically, when the yellow and red lines are lowest, these are the best times on the moon.
  • VHF-Chat - This is a Slack group for all things VHF. EME, MS, Trop, grid chasing, etc. You can join using this link.
  • Old school EME chat page - Still in use, don’t know why but old habits die hard.
  • HB9Q Chat - Typically used on 432mhz and above.
  • When in the moon up? This link is great to show where the moon is with real time tracking (click the live button if its not already selected) For the W2/Jefferson station.

Additional notes:

  • 144.100-144.150 Typical JT65B/Q65A EME Window
  • 144.200 2m national calling frequency USB
  • 144.205 Morning SSB activity
  • Sunday morning net 144.250.5 Sunday AM 9AM EST Point to NYC
  • 143.050mhz GRAVES space tracking signal (While France still has moon visibility)
  • 144.174 FT8 2m Freq (Use the built in FT8 RHR Client :-)
  • 144.270-144.300 CW beacons
  • 144.390 FM APRS Packet Traffic
  • TX is blocked about 144.300 (antennas are not resonate outside EME band)
  • Check the station tab at W2/Jefferson for beacon list.

If I am missing something that needs to be added or you would like some clarification on the process please send a ticket to support and I will do my best to make the adjustments.

GL DX and let us know if you have success working your first DX station off the moon! If we hear there is interest in EME operation we can start thinking of expanding opportunities.