"Set Top Boxes" for DATV

[G0CFD]

Hi All,

As a toe-in-the-water for DATV, I'm looking for info on the suitability of standard off-the-shelf DVB-S/S2 or possibly DVB-T and/or combined receivers. I think some Comag boxes for example will receive some DATV transmissions, but which models will work and at which symbol-rates and FEC settings? Also, I want eventually to view Es'Hail which I understand requires S2 RX capabilities for the beacon and RB down to 125KS/S, so again which ones work?
I know I could build the MiniTounier or Ryde RX, but that's for the future.

I've looked through the forum and there's snippets of info in various threads, but they get too deep for the likes of me who's just looking to start DATV.
There's loads of surplus boxes around on fleabay and lurking in peoples cupboard that I'm sure can do the job very cheaply, so which should I look for and which should I ignore? I'm aware that generally Sky boxes in their various guises aren't suitable, but is that the case for all of them? Also, many models are clones with different fronts and labels, but the same chipsets etc. so again what's good or bad?

It crossed my mind that I could add a spreadsheet to this thread where people could add info for the benefit of the like-minded starters or a reference point.

Thanks,

Frank.

[G3GJA]

Hi Frank

There are some 'HD' FreeSat satellite set top boxes that will do MPEG2 and H264 compression. The big problem is that most set top boxes will not work on the low symbol rates that are now in common use on 70cm and 23cm.

The Comag SL30 / SL65 only do MPEG2 down to 2000kS/s. There are several HD STBs on Amazon that do H264 down to 1000kS/s as well as MPEG2 down to 2000kS/s. These will probably be Ok to view a strong local repeater. Don't forget to disable the LNB powering via the coax.

I've tried a few STBs when I was looking for a receiver for our local repeater GB3EY, but they all had niggles, such as sometimes working down to 1000kS/s with MPEG2 but not reliably. Some days it would just not work.

Your best route is the Ryde set top box project or just add a Minitioune receiver to a Porstdown 4. Then you will be able to receive symbol rates down to 125kS/s or lower.

Clive G3GJA

[AdrianH]

Unfortunately Frank, as most people and sites, push towards, higher compression with H265 and narrower bandwidths say 500KHz and less, does leave potential interested users with little choice other than buying a purpose designed receiver.

When I first started to play with satellite reception I used one of the handheld boxes at around £40 from Ebay to see if I could decode the beacon from QO100, at the time it was 2 MS bandwidth. the box would decode down to 1 MS and do H265, but 500 KHz or lower it would not decode.

The terrestrial repeaters are also going the same way requiring H265. For example, the local transmitter is set to 1315MHz DVBS-2 H265, symbol rate 500k and FEC 2/3 so makes it difficult for someone who may have an interest in ATV, to see if they can receive a signal at low cost with a domestic set top box. Some repeaters also broadcast signals during periods of inactivity, some do not. So having a constant signal to pickup is not always the case.

So Minitiouners of various types or the latest Ryde/Winterhill or other dedicated receiver purchases may be the only way to go.

On saying that there is an alternative if you are OK with software under Linux. There is a software package the uses the RTL-SDR sticks, the type you can pickup for around £20 again from Ebay or you may have one already. It uses a package called Lean-DVB sending the output as a TS stream to VLC.

See the following link: - http://www.pabr.org/radio/leandvb/leandvb.en.html

It could well require a decent PC to operate, I did use it to decode signals again when first starting using an i3 laptop, but it soon ran out of processing power, so a better one was required. The RT-LSDR sticks can go to 1.7GHz so can cover the satellite IF signals from LNB's or the local repeaters on 23cms.

Sorry for the long post.

Adrian

[g8gtz]

Frank,

The bottom line is there is no reliable and easy to use solution for DATV and that's why we developed the Ryde receiver - take a look at the Ryde requirement spec opening statement: https://wiki.batc.org.uk/Ryde_Requirement_Specification

73

Noel - G8GTZ

[DG8KD]

Hi,

before purchasing a off-the-shelf STB, may have a look here:
https://www.wimo.com/en/pf-rxsat

MiniTiouner ready to use.

73
Rainer

[g0mjw]

Beware that model! Take care 12V is not wired directly to the connectors.

The Minitiouner is easy to build but there are ready made versions available from REF. Trying with a STB, Even the Octagon 8008 is likely to result in frustration and discouragement.

Mike

[G8GKQ]

The Elad "E-Tiouner DATV Receiver 250-2450 MHz" makes some very misleading claims on their website: https://int.wimo.com/en/pf-rxsat

The PF-RXSAT uses a FTS-4334L tuner, which is typically used in DVB-T set-top boxes (satellite receivers). The universal interface via I2C bus control makes this tuner easy to use in amateur radio projects. The reception range is from 250 to approx. 2450 MHz, covering the three amateur radio bands 70cm, 23cm and 13cm without the need for additional down-converters. Of course, commercial DVB-T or DVB-S signals can also be received.

The FTS-4334L tuner has no capability to receive DVB-T and it is not used in DVB-T set-top boxes. A worrying lack of accuracy.

Dave, G8GKQ

[df3ei]

Hi,

I would add that indeed for any serious satellite sleuthing of the QO-100 or terrestrial TV-DX the MiniTiouner or Ryde would be the way to go. There you have not just a receiver but a tool that can tell you an awful lot about the signal, e.g. why a strong enough signal would not decode or similar debugging information.

I am using a couple of Octagon SF8008 in a repeater setup, sitting on a single channel with fixed parameters (down to 250kS/s reliably). But they are not good for anything else and not cheaper than the above mentioned alternatives, either.

Good luck and stay healthy,

Jörg

[G0CFD]

Hello all,

Many thanks to everyone for your quick replies and the info.

I think you've all really discounted the idea of using the commercial STB's as being of variable and uncertain suitability, so to avoid being disappointed and wasting my time and money I'm going to build a Ryde. Before I take the plunge though and yes, I've read the spec, I've got some questions I am sure you knowledgeable peeps can answer please:

Does the MiniTiouner/Ryde support all the current modes in use in the UK/Europe and on QO-100 including the beacon and will it support all reasonably expected future digital modes ?

I note there is mention of a new integrated board for the Ryde which I presume puts the tuner, breakout points etc all on one board which will connect directly to the Pi headers, avoiding the need for the USB interface module currently used on the MiniTiouner. Any ideas when that PCB will be ready please because I don't want to buy/build something today that will be "out of date" next week? I know it's a continually moving target, but any heads-up would be good please. I'm not desperate to start the build but will hold off for now if it's not far away.

Anything else I should know?

Many thanks,

Frank.

[G8KWR]

As someone new to DATV last summer I bought a Comag HD set top box on eBay and am using it to pick up my local repeater GB3UD. Works fine for that repeater. Then went on to put together a Portsdown 4. Really enjoying it. Good luck.