Newcomer to ATV

[M0RFU]

Good Evening All

I have had a passing interest in ATV & the Microwave Bands since I was first licenced back in 2011, however time and space have not been kind, however the upcoming commissioning of the geo-stationary sat gave me a push in the right direction.

This combined with the desire to get a SDR to complement some of my other kit led me to ordering a Pluto SDR, i had decided that this was the ideal kit for me and was very pleased to see that there was pretty good support for it in DATV Express and GNU Radio. GNU Radio on Linux would be my first choice but as it arrived today whilst at work I through DATV onto my work Windows Laptop and once I was home I dug out a Comag reciever that I had rescued from the tip a few years ago. Once the kids where in bed and the Mrs was out, I started playing and am happy to say my current 23cm DX is about 2 meters Ill get setup in the shack tomorrow when there real work will begin.

Anyway onward and upwards, the plan is to invest in both setting up the 23cm datv and following from the great guide on here a 5.6ghz analogue system, mostly for portable use.

As a member of RAYNET here in Manchester I am hoping I can convince a few others to give it a try.

73 for now and I will hopefully update on my adventures soon.

[g8ayc]

Welcome aboard, pleased to see another join this rather specialised hobby. Looking forward to hearing about your progress.

73 Nigel G8AYC.

[M0RFU]

Thanks Nigel

I also joined the BATC on friday so I am a fully fledged member now.

I have managed to get a bit more time on the laptop and have been emerging myself in GNU Radio, so far I have built from scratch a NBFM TRX, its a bit rough and ready but works. I also have an example DVB-S example that I found working with the PLUTOSDR, so all in all good progress, just working out what steps are required for the DVB-S transmitter so I can import my own live video and test cards.

On the receiver side I have dug out another Sat receiver, this one is a SKYBOX F3S (Nothing to do with SKY) i picked it up at a carboot after sky had blocked the card sharing services so it was a couple of quid. I never really liked the interface, which it why it was in a box, but it is very configurable, with Symbol rates down to 1000ksps working just fine. The main advantage is it has HDMI which means I can connect it to one of the main tvs in the house allowing for testing when I cannot get out to the shack (its down the garden) and then the Comag can go out to the shack for use there.

M0KPW's website has really given me a interest in what he is doing and I think I will be looking to have something up and running on that band for the summer.

Hopefully I can find someone nice and close by who I can run tests with, I know there used to be a few but not heard them on the talk back for quite a few years. My first ever QSO was with M0ATV on 2M SSB, he explained to me about ATV, but I have not heard him on for a long time.

Jon

[g8ayc]

Hi Jon,

Sounds like you're making good progress. I'm a beginner myself in DATV. Many years ago I used to be on the air on 70cms with analogue AM modulated transmissions on 405 lines - that dates me!

If you are within range of an ATV repeater, it's likely to have BATC streamer access which means you can monitor locals and is also useful for doing TX tests.

73 Nigel.

[M0RFU]

Well according to the COVERAGE MAP on the ETCC site I should be in range of GB3UD, however I do not have enough knowledge of how 23(24)cm works to know if it is a path that is workable.

Line of sight ignoring the curve of the earth would say yes, but the curve makes it more questionable.

I might throw together a biquad and stick it on a dish to see if I can pic up anything from it at all.

[g8ayc]

I saw you comment on getting a dish. Any ideas? I was looking at http://www.systemsat.co.uk/solid-satell ... tings.html or maybe the 1m one.

73 Nigel.

[M0RFU]

There is a shop not too far from me that has 1.1m dishes for £30 which if I can get away with will be ideal. But I am interest in finding out what is the smallest I could get away with as if I plan to transmit I will probably end up with two dishes.

Been thinking about mounting options, I am lucky that I have a shack at the end of the (small) garden, which really helps on HF but causes issues with anything VHF and up as I have no height.

That being said I have a decent line of eight to Oscar100 so pretty lucky.

[g8ayc]

I heard someone on SSB who was running just 3W to a 1.1m dish. Obviously TV will need something more! I think someone said that they were copying the video from the satellite with a 60cm dish.

If I have a dish near the ground (so I can experiment) it will have to be at the end of the garden so I'll have a 25m cable run into the shack.

[M0RFU]

I suppose it depends on what your recieving on, for the narrow band reception it wouldn't be too bad to mount something like a raspberrypi and RTLSDR on the dish to minimise the run. For the TV however that might be trickier, but not Impossible, depending on what your planning to receive on.

Lots of options really. I'm trying to get as much reading done on these higher bands.l before I spend too much money, so I know what the direction I want to head in. Could also do with finding a local to do experiments with.

I might go and align my small dish this evening and see if I can get anything on the RTLSDR.

Where abouts in the UK are you?

[g8ayc]

I've just got hold of a Minitiouner Express for DATV reception. It's quite versatile as it goes down to 144 MHz and up to LNB output frequencies. Thus it will receive the 741 - 749 MHz output from an unmodified LNB. I'm hoping the LNB will have sufficient output to overcome the attenuation of the long coax.

I'm in Newbury, Berkshire.