There is short description of my 23cm EME setup:

Since October 2020 the EME part of 23cm band as well as 9cm, 6cm and 3cm bands are fully banned or hardly limited ( EME use) for Amateur radio operators, so no more plans to be active on 23cm from Israel…

Shame on IARC (Israel Amateur Radio Club), no HAM spirit in this organization anymore…

In addition in  December 2013 my EME dish was damaged by hard snow load (snow in Israel !!! – I’ve not designed mechanics for this case), so since this time it is not operational for EME and used for Satellite TV.

• First one is initial variant  that uses unmodified  1.8m dish and Azimuth/Elevation mechanic

My first QSO with PI9CAM was done at 8:40 UTC 10-07-2010 using 1.8m dish and 10W output power.

Next step –  I added to the dish above 1.8m dish “extra size”, extended it by mesh up to 2.6m diameter, shape is not exactly parabolic, but gave me gain improvements close to expected

So my present EME Setup is:

Transverter: self maid  1296Mhz/28Mhz + Yaesu FT897D / AFEDRI SDR (on RX)

Antenna: 2.6m dish (1.8m SatTV dish extended by mesh)

Feed: OK1DFC

LNA: G4DDK ~0.3dBNf

There you can download and hear recorded I/Q file of DUBUS CW EME Contest that was done on my system using AFEDRI SDR receiver + 1296MHz/28MHz transverter.

next page has information about my dish’s Azimuth/Elevation control.

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Azimuth / Elevation mechanic and control

Azimuth movements is done by AlfaSpid BigRAK rotator, controlled by its own control box.

Elevation movements is done by 36” linear actuator for Satellite TV, controlled by home maid control box with microprocessor MSP430F149 from Texas Instruments.

To calculate real elevation angle – the elevation controller uses simple algorithm, where number of pulses (from embedded in actuator pulse encoder), actuator and dish mounting geometric dimensions  are used in elementary triangle equations  see image below:

We can see triangle that is formed by dish support two sides “a” and “b” and linear actuator “c”,

where sizes of two sides “a” and “b” is constant and one side “c” – has  changing size that in reality defines elevation angle of the dish. Size is changing, but we can know it with relatively high resolution using actuator’s encoder pulses. relation between sides “a”, “b” and “c” is defined by next equation:

c² = a² + b² – 2*a*b*cos(angle_between_sides_a_and_b);

So we can easy calculate angle_between_sides_a_and_b (in degrees) and from equation below find elevation angle:

elevation_angle = 180 – offset_angle – angle_between_sides_a_and_b;

where: offset_angle – is constant angle, that defined by dish support construction (can be easily measured or calculated).