[vdr] Re: VDSB solved, need fix...

[Klaus Schmidinger <Klaus.Schmidinger@cadsoft.de>]

Vladimir Shved wrote:
> > -----Original Message-----
> > From: vdr-bounce@linuxtv.org [mailto:vdr-bounce@linuxtv.org] On Behalf Of
> > Klaus Schmidinger
> ...
>
> > > Does it make sense? V2.0 commands actually allow communicating with
> > diseqc
> >
> > > switch.
> > VDR only sends DiSEqC commands through the card it wants to tune.
> > If such commands reach a switch that isn't even connected to that
> > card, I would assume something with your cabling or with the two
> > switches you are using is wrong.
> >
> > I also wonder how you can connect one LNB to two switches?
> > You should rather use a so called "multiswitch", where you can
> > connect the four lines of an LNB to the inputs, and 4, 6 or 8
> > (depending on the kind of multiswitch) receivers (i.e. DVB cards)
> > to the outputs.
> >
> > I don't believe DiSEqC 2 would make any difference here.
> >
> > Klaus
>
>
> Dual output LNBs - lnb with two outputs, from there you can hookup 2x4/3x4
> or 2x8/3x8 switch and get 4 or 8 outputs from lnb and then each of those
> outputs can be hooked up to the 4x1 diseqc switch. Much cheaper than buying
> multi-switch, in US they don't even make diseqc multi-switches, at least I
> did not see one. I did not have chance to play with diseqc multi-switch but
> I think it should suffer from same problem.
I'm using a DiSEqC multiswitch with 8 inputs (2 LNBs with 4 lines each)
and 8 outputs and have no such problems.

> I did rule out wiring problems, I used high quality cable and connectors in
> my setup. Diseqc command signal goes through LNB, I'm sure. Also according
> to this document:
> http://www.satlex.de/en/diseqc_technicians-page_13.html
> you can cascade diseqc switches, which means it will pass diseqc commands
> through itself to LNB #1 input and LNBs are not smart enough to block it on
> 2nd input. Obviously 2x4/3x4 and 2x8/3x8 switches are not any smarter. So
> when you send diseqc signal from one card, it reaches LNB and from LNB it
> goes to second diseqc switch and possibly to second card. I wish I knew how
> to test this correctly. Is there any way to receive diseqc commands with DVB
> card? Need some sort of diseqc sniffer tool? Sorry I'm very new at this and
> know nothing about it.
I find it very strange that a DiSEqC switch would react to control signals
that come in through its LNB inputs. I'd certainly call this "broken".

> Diseqc v2.0 allows bi-directional communications, while diseqc 1.2 only one
> way. This should allow controlling individual diseqc switches, either in
> parallel or in cascaded operations. I believe everyone in US is using
> parallel operation in multi-card setup.
With the proper DiSEqC sequences it should be no problem to address
individual switches, even with DiSEqc 1.

Klaus