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So far, I have bought an RPi 4 with 8GB memory, the RPi Pi 7" screen, the RPi PSU, and a nice looking heatsink enclosure which won't mount on the back of the screen. I guess I'll need a longer ribbon cable for that.
My ultimate goal would be to use OBS as the AV source and send it's output to the RPi over ethernet. Will this be possible? If not, can it be connected by USB?
For the RF side of things, I appear to be overwhelmed with choice, but I can't figure out which of the choices are capable of satellite TX and RX and which are not. Do I need separate modules or would one do both? I would also like to be able to control the whole caboodle over eithernet using a web browser.
Although I've constructed many things in the past, I'm now 75 years old, grumpy and impatience, have less physical skills and my eyesight is failing. Off the shelf items, like the Pluto for example, look more attractive, but I should be OK with minor modifications when neccessary.
This is turning into a rant, so I'll get to point...
Please can someone tell me which module or modules I'll need in order to TX & RX via O~SCAR-100? From my EA7 QTH in Málaga, what size dish will I need? Which LNB should I buy and will it need modifying? I assume a POTY or PATCH is easiest, but which one and where from, and can they be bought ready built? Etc, etc, etc.
Sorry for so many questions, but there are no ATV clubs in this part of Spain.
I would make the suggestion that you follow https://batc.org.uk/live/oscar100net on a Thursday night at 20:00 UK time. Generally lasts between 1 and 2 hours. There is a weekly net on the satellite that is streamed on this URL. I have learnt a lot listening to the various participants talk about their installations and projects.
Good luck, Roger G8KWR
I'll answer the Portsdown bits of your question and add some basics for QO-100.
You can use OBS to send a transport stream over Ethernet to the Portsdown. Equally, the the Portsdown can be used with directly connected video sources such as the Raspberry Pi Camera or a C920 WebCam to get you started.
You can either use the LimeSDR Mini or the Pluto with the Portsdown 4 to generate the signal for the satellite. Either of them will get you a few milliwatts at 2400 MHz.
You will then need a power amplifier up to about 40W (linear) at 2400 MHz. This generally needs an amplifier rated for 150W CW or so. Dish size is more or less independent of location. 1.2 metre is a good target size. The Bullseye 10 kHz stability LNBs sold by the RTL-SDR people are a reliable starting point for receive. You can use the LNB for receive only without a POTY, and then modify it for use with a POTY once you get one.
Hope that helps with some of your questions.
I've just got the Portsdown 4 software installed and successfully stream the test card to the BATC site. On the Video Source menu, I don't see a button to select a transport stream. Then how would I address the pi from OBS?
You can find the "IPTS in" button on the "Encoder" menu. The logic is that you are using an external encoder....
But it won't work for streaming - only transmit.
You need to send the IPTS from OBS to the Portsdown's IP Address on port 10000.