DVB-S2 card, 9x16 multiswitch - how to switch from Sat 1 to Sat 2?

[riccume]

I'm trying to figure out which DiSEqC commands (or Tone Burst?) my TBS 8921 DVB-S/S2 tuner card should send to switch from Sat 1 to Sat 2. Unfortunately I don't have full access to the details of the multiswitch since I live in an apartment building which has recently been wired for Sky and Hotbird; I contacted Triax for the manual but no luck so far. My previous card (Compro VideoMate S350 - I had to change due to BBC HD moving to DVB-S2) was oblivious of DiSEqC and happily tuned Astra. When I tried to do the same with the TBS 8921, it would only pick up Hotbird.

The lay-out is the following:
- 2 Quattro LNBs, feeding Astra 2 (Sky) to the four Sat 1 inputs, and Hotbird to the four Sat 2 inputs (it could be the other way around, this is what the installer told me when contacted but he wasn't too bothered)
- Triax TMP 9x16 multiswitch, which feeds the flats

I've tried with several viewer programs to send DiSEqC signals (Pos A/Osc A, etc.) to the multiswitch and I get Hotbird in Pos A/Osc B, but no Astra. Finally while playing with TVSource I tried the configuration with no DiSEqC signal for Astra ("None" in the drop-down menu) and "Pos A/Osc B" for Hotbird, and it worked correctly!

Can anybody guess what is going on here? This setting looks strange to me... but it works. Thanks!

 

[rolfw]

That's correct, the Astra signal should be received with no DiSEqC command, as it's on input A, Hotbird needs to be on Input B as you've set.

 

[Robbo]

Normally that arrangement would be wired with 28.2E on position 1 and the other satellite on position 2. That is because Sky and most Freesat receivers can't issue Diseqc 1.0 commands. Not sure what Osc B refers to? The LNB should be set to universal for both satellites. If nothing has been changed since you had your old card, Astra will still be on position 1.


Setting one of the satellites to 'none' in the diseqc menu could be a bad idea, as when the switch was previously on a position, it will stay on it when none is selected.

 

[riccume]

Thanks rolfw and Robbo. What you say makes sense, just I don't understand why if I set Astra on DiSEqC command "Pos A/Opt A" (or LNB1 in Windows Media Center) it doesn't work, no signal. The only way I get Astra is by setting the DiSEqC entry in TVSource to "None" - but then in WMC, if I say that I receive only one satellite (i.e. I don't go to the DiSEqC page), it picks up Hotbird. Something wrong with the card (or card driver), or something I don't understand on the way the switch works? (i.e. maybe it switches by Tone Burst?).