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

[Vladimir Shved <vshved@logistic-systems.com>]

> -----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 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.

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.

	--Vlad