23cms datv standard freq ?

[m1cdq]

As i am fairly new to DATV and i've been hitting google and the batc wiki.
I know the talkback freq is 144.750Mhz
but the actual datv signal
going by the wiki

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The UK allocation is from 1240 MHz to 1325 MHz and common ATV usage is as follows:

1248 - 1249 MHz = repeater inputs
1255 MHz = simplex
1275 MHz = simplex or alternative repeater input as determined by the CAA (primary user).
1300 - 1325 MHz = repeater outputs

So 1255 seems to be the simplex freq
but as per the rsgb bandplan
In order to prevent interference to Primary Users, caution must be exercised prior to using 1250-1290 MHz in the UK.

I know there are different SR and FEC to use. this give over 30 different combinations not forgetting dvb-s and dvb-s2 & mpeg2,h265,h265

so is there a default tx calling ie 250 fec 3/4 or 333-7/8 dvb-s h264 and a freq
so people can just leave a reciever running in the shack and not have to twiddle
yes the fm is easier just leave it on a freq and wait

and don't get me asking about repeaters. trying to find out what some are on what sr and fec ect. even on the repeaters own webpage you have to hunt for the info

[g8lce]

Have you RXed your nearest DATV repeater? I think it is GB3EY http://www.southgatearc.org/news/2019/a ... dzxltXgq00 ?
Living in that part of the world is probably better for RXing DATV as there seems to be more activity ( I live in Cornwall ). If you are looking at DATV activity then go to Oscar 100. All you need is a 1metre plus dish and a SE view. Then it is just getting the bits together.
The other thing that is coming along is a spectrum scanner for DATV that shows the various modes and frequencies over a 8Mhz band. viewtopic.php?f=105&t=6334
Down here most people would use a Satellite RX so 2000sr would be the norm.

Martin G8LCE g8lce.com

[m1cdq]

cant receive EY from here even on a 23 ele tonna and preamp. I have two 1-meter dishes up for oscar 100


2m+70cm+23cm and 2.4 ghz beams up
have one mini-tioune up and running building another to go with the portsdown Im building

busy 3d printing parts for antennas for portable use, 2,70,23 bands
also uplink for oscar 100

featured_preview_Universal_Screw_LNB_3D_printed_Helix_v1_2000.jpg (21.8 KiB) Viewed 3039 times

featured_preview_20191004_133613.jpg (31.33 KiB) Viewed 3039 times

https://www.thingiverse.com/thing:3903285

and another tonna this one 18 elements

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excuse the mess Im messy when building stuff
my purple power 2/70 beam works very well

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51.200 ??
71.000
146.500 MHz Centre frequency for wideband modes
437.0000 Experimental DATV Centre of Activity
23cm band ???
2301.100 MHz Wideband Data/DATV

seems to be no centre of activity for 23cms

[G3GJA]

I am doing most of the engineering on GB3EY and I'm based just to the west of Hull at Anlaby Common. I’ve just seen your post on the forum.

You should be able to receive EY; the attached archive is the web output from RadioMobile Online showing the path to you QTH. With a 16dBi gain antenna at 6m you should be getting at least 9 microvolts into a preamp. That from our experiments is enough. The repeater has been seen at Royd Moor 79km from EY. I’ve also attached the predicted coverage from the ukrepeater.net site for your area.

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Re your other queries, 1255MHz is not used in this area because it is occupied by the CAA radar at Claxby on 1254.5MHz. Operation below 1250MHz might be possible with a DATV signal but the older analogue ATV input frequency of 1248MHz is unusable because of the wide bandwidth and radar issue. Generally it's best to listen on 144.750MHz and then set up compatible standards for the vision link.

1265MHz has been assigned as an input frequency for EY and 1280MHz for GB3GG. 1265MHz is too close to the Claxby radar to be usable so it's likely that we will have to use 1280MHz as well and that might well be used for local simplex too. All of this is subject to change because of Galileo. In the 1990s 1288MHz was used for analogue FM ATV in this area and it may be good for DATV.

Information about GB3EY can be found in the Repeater section of this forum. It's currently running DVB-S at 2000kS/s, FEC 3/4, MPEG2 on 1308MHz. There are no inputs at present and no audio channel.

Clive G3GJA / G8EQZ