Gabriel,
I do not know if available in EU, but I used an 86cm offset feed dish originally used for Ku-band satellite TV here in the US for receiving AO-40 2.4 GHz telemetry. It used a six turn helical feed and db6nt preamp to Drake downconverter to 123 MHz IF (FT-847).
I use a 60cm offset feed dish, commonly used in the lower-48 states of the US for satellite TV for my 10-GHz station. Feed is W1GHZ linear pol feed with corrugated horn. Most likely you will need a CP feed for Oscar-100. http://www.kl7uw.com/Another_Dish_Tripod.pdf
Many eme'rs are having success on 10-GHz with as small at 60cm though 1m is better (for eme). I suspect Oscar-100 signals are much stronger than eme.
I am not QRV on satellite at present but have plans to restore my AO-40 antenna system this summer using a FT-736R on mode-UV or LU sats. photos of my old system: http://www.kl7uw.com/sat.htm
73, Ed - KL7UW
----------------------- Date: Fri, 15 Feb 2019 08:55:48 +010 From: "Gabriel - EA6VQ" ea6vq@dxmaps.com To: AMSAT-BB@amsat.org Subject: [amsat-bb] dual dish feed for Oscar100?
I am looking for a dual band dish feed for 10GHz/2.4GHZ to use for the Oscar 100 downlink/uplink.
What is your recommendation of either a commercial or a simple to build one?
73. Gabriel - EA6VQ
73, Ed - KL7UW http://www.kl7uw.com Dubus-NA Business mail: dubususa@gmail.com