23cm EME Equipment - Block Diagram

 

 

Above is a block diagram of my 23cm EME station.  Click on it to see a larger image.  Note that the Leo Bodnar GPSDO injection board is actually installed inside the Icom IC-9700.  (See this Post - Leo Bodnar Installation)

 

All my 23cm EME Equipment "lives" on a 3-shelf rolling cart which stays in the garage along with my folding dish antenna.  When I plan to operate on EME, I simply roll out the cart, install the 2.4m folding dish, and connect the cables.  There are 3 cables from the Sub-Lunar SL-1 Az-El rotors to the WinTrak controller - the SEI controller Bus plus the Azimuth and Elevation power cables.

Then there are the two RF coaxes (Tx and Rx) which connect from the dish to the AG6EE power amp.  The Rx cable connects to the AG6EE preamp and the Tx cable to the OK1DFC Septum feed.  The TX cable connects thru the sensor of the WaveNode RF Power Meter and to the output of the AG6EE power amp.  The Rx cable connects to the AG6EE power amp which has sequenced DC voltage to feed the preamplifier through the coaxial cable.  The preamp also contains a built-in relay and dummy load and it connects directly to a septum or patch feed without the need for an adapter or coax jumper.

Once everything is connected, it is time to calibrate the dish's pointing location.  If the sun is not available, I can use the Theodolite app on the iPhone to get the Az and El of the moon and enter that into WinTrak.  If I have the sun, it is simpler to point the dish at the sun so that the square shadow of the Septum Feed appears on the exact center of the dish.  Then I press the calibrate button on the WinTrak software of the WinTrak controller and it will keep the dish pointed at the moon all the time.

You can see a 45-second video of me setting up the entire station on another Blog post "Setting Up the 23cm EME Station." There is a link in that Post to the video.  Clicking on that post will open in a new window. The setup of all the equipment actually took 19 minutes but the video was compressed to just show the basic operations.

Below is an image showing how the sun's shadow appears on the center of the dish for calibrating the antenna.

Setting Up the 23cm EME Station

My 23cm EME station is not "permanent."  It is essentially a "portable" station.  All the equipment is located in my garage.  The 2.4m folding dish lays on the floor along with two AC extension cords plus the M&P TX and RX coax cables, and the rest of the equipment is on a 3-layer rolling Service Utility Cart. 

To set up the station, I roll out the utility cart containing the equipment plus an office chair, roll out and connect the AC cords, and power on the laptop, the PowerWerx 13.8VDC supply, and the WinTrak controller.  Next I install the SubLunar SL-1 Az-El antenna controllers on the tripod which is tied down to the edge of the driveway and secured with a spiral Earth Anchor.  Next I mount the folding dish to the SL-1 mounting bracket and connect the SEI bus and Az-El power cables from the SL-1 to the WinTrack Antenna Controller. Next I start the WinTrak app on the laptop. Now I unfurl the dish (a step ladder and yard stick is helpful to make sure the perimeter wire on the dish is not caught on anything.)   Once the perimeter wire is clear, I expand the dish to stress it into a parabolic shape and lock it into place.  Next I tell the WinTrak controller to bring the dish down to where I can connect the TX and RX cables to the OK1DFC Septum Feed and to the AG6EE power amplifier.

At this point, the equipment is connected and ready to use.  I shot a video of this process and then compressed it to a total running time of 45 seconds.  The actual setup of the dish and equipment took 19 minutes.  You can view the video here: Antenna Erection Video.  This video will open in a new window.