First commercial sat RX found which supports RB-TV <1MS

Ideas, technical topics, help and discussion for ATV enthusiasts
Forum rules
This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.

Thank you
Post Reply
gw8bvi
Posts: 3
Joined: Tue May 02, 2017 4:59 pm

First commercial sat RX found which supports RB-TV <1MS

Post by gw8bvi » Wed Jul 25, 2018 3:25 pm

Severnside ATV Group has found what we believe to be the first commercially available satellite receiver box which supports symbol rates below 1MS/s

It works down to 250 kS/s DVB-S, and down to 400 kS/s DVB-S2 QPSK (250 kS/s 16APSK).
It supports the de-facto RB-TV symbol rate of 333 kS/s, 7/8 FEC.

Up until now you were restricted to using Minitiouner for receiving low symbol rates below 1MS/s.
The unit is the ZGemma H9S Enigma 2 Linux smart box. Other satellite receivers are available, and we will continue testing others hoping to discover more that support low symbol rate RB-TV.

The unit needs to be used with an RX upconverter such as the SUP2400 (BATC shop) for 70cm, because unlike Minitiouner v2 (BATC shop) the H9S tuner only covers the standard 950 to 2150 MHz satellite IF band.
For the new NoV 2m allocation at 146.5 MHz you will need a 2m to 70cm upconverter + SUP2400, or a 2m to 23cm direct upconverter (the SUP2400 doesn't work below 250 MHz input).

The H9S supports Mpeg2, H.264 and H.265
I tried it with 333 kS/s H.265 DVB-S from my DATV Express exciter, and the results were excellent.
The setup menu is very non-intuitive, so I intend to write up a guide for CQTV.
The H9S tunes 23cm DVB-S directly. I had it decoding GB3ZZ's 4MS/s digital output, which is a two channel multiplex - no problem once manually tuned in.

Phil GW8BVI, Caldicot S.Wales

G8XZD-TV
Posts: 109
Joined: Fri Feb 22, 2013 6:41 pm

Re: First commercial sat RX found which supports RB-TV <1MS

Post by G8XZD-TV » Thu Aug 02, 2018 4:28 pm

Very interesting find, thanks Phil.
Have you tested how does it performs over the air - say compared to say Minitioune and a SUP2400?
I know some of the "do everything" receivers take an age to lock up
So in your opinion would it be a good one for repeater service or too fiddly?

73. Ian, G8XZD.

M0DTS
Posts: 656
Joined: Sun Feb 24, 2008 9:03 pm

Re: First commercial sat RX found which supports RB-TV <1MS

Post by M0DTS » Sun Aug 05, 2018 5:12 pm

as above, i would be interested in it's performance compared to minitioune at 333 ks for example inc decode delays.

Rob

gw8bvi
Posts: 3
Joined: Tue May 02, 2017 4:59 pm

Re: First commercial sat RX found which supports RB-TV <1MS

Post by gw8bvi » Tue Sep 11, 2018 12:08 pm

Hi All, I still have the unit on loan but haven't had any time to go on air and test the zGemma at 333kS/s RBTV to see how it compares with Minitiouner for lock time etc. It would be interesting to see how stable it is for use at a repeater site, and what it does after power loss / restore. 73, Phil GW8BVI

Post Reply

Return to “General ATV Discussion”