Hauppauge NOVA SE2 - Missing H Channels

[newyankee]

Hello sub,

let's log. I will be happy to install the *.dll and post the logs.
Diseqc C -> LNB 2 is not really a problem, now that I found that out I can simply add a second source using the 'wrong' option, and I don't need more than two (for now...).

The bigger problem really is the missing high band.

I am starting to understand why that may not be an issue for you. I assume that you are using some of the optus sat's. They only have high band transmissions and as such, you may only use single band LNBs, thus you only need to switch positions but not lo/ hi band.

G

[sub]

Try the attached file. It'll add the raw diseqc commands to the -native log file.

[newyankee]

The log is attached. Without having checked the raw diseqc command for correctness, I noticed that the command is only sent once at the beginning of the scan.

This partly confirms my previous hypothesis that if you only need to switch positions, you only need the command once and afterwards, only H/V switching will suffice.

My thoughts are as this: As soon as a transponder to be scanned is above the LNB switching frequency, a corresponding command ("switch to hi band now") needs to be sent again. Same for lo band, if a lo band TP is in the list. I couldn't find a second diseqc command in the log...

Does this sound reasonable?

G

[sub]

My understanding of this is very murky, so I'm not in a good position to speak authoritively on the matter.

Ignoring the diseqc switch part of the question for now, GB-PVR uses the Microsoft BDA driver interface for its tuning, which effectively sets a lot of tuning parameters (frequency, symbol rate, polarity V/H etc) then submits the tuning request to the BDA drivers which takes care of the rest. Behind the scenes the driver will be interacting with the tuner to lock the frequency etc, and most likely telling the LNB the polarity etc, but none of the details of this are visible to me. This default behaviour works fine receiving channels on both horizontal and vertical on single dish/lnb setups.

When you use one of the devices that GB-PVR tries to do diseqc support for (Twinhan, Hauppauge, FireDTV), then it does these exact same steps for submitting the tuning request, but follows this by doing some vendor specific stuff to submit the diseqc command. In the case of the Hauppauge card, this involves sending the raw diseqc command to the switch. It currently sends the diseqc "Write to port Group 0 (commited switches)" command, which reading the documentation sounded like the corretc thing to do.

I dont currently ever ask it to switch to the hi band or anything like this, it all happens behind the scenes in the drivers when I submit the tuning request.

[newyankee]

Happy new year, sub!

My switch works fine with the Hauppauge WinTV soft and four other analog and digital STBs.

The problem may be this:

...submits the tuning request to the BDA drivers which takes care of the rest. (...) This default behaviour works fine receiving channels on both horizontal and vertical on single dish/lnb setups.

This works in default stage, but I am not sure if the BDA driver does switch the 22kHz tone on/off for band selection.

...but follows this by doing some vendor specific stuff to submit the diseqc command. In the case of the Hauppauge card, this involves sending the raw diseqc command to the switch. It currently sends the diseqc "Write to port Group 0 (commited switches)" command, which reading the documentation sounded like the correct thing to do.

I am sure it primarily is the right command. But as soon as a diseqc switch detects a valid diseqc command, it abandons backwards compatibility mode, thus it expects modulation of the 22 KHz tone with a valid diseqc command for all future switching.

I dont currently ever ask it to switch to the hi band or anything like this, it all happens behind the scenes in the drivers when I submit the tuning request.

I have done some further investigation: In diseqc mode, the switch always keeps the last stage (band/position/option). After setting the band (lo/hi) and polarity (V/H) using the hauppauge WinTV soft first (that is set to diseqc 1.0), the switch stays on the high band and H polarity and doesn't fall back until a next diseqc command tells it to select the low band lnb output. I can then tune the high band in GBPVR temporarily. Apparently, anything happening in the drivers will be ignored because diseqc mode has been set earlier.

In essence, I think that the diseqc commands will always override what comes from the tuning request to the BDA driver including H/V switching(which may or may not send analog switching criteria). Therefore, I suggest the diseqc commands need to be sent each time the tuning request involves switching to a different polarity/band/position. Considering the bus spec includes hex commands for each criteria, I can't think of anything else.

G

[sub]

Do you have a link you could recommend that gives a good description of what part the band plays in all this? I've spent the last hour or so having a read on the net but found very little information on this.

When I submit the tuning requests via the BDA interface, band is not one of the parameters it accepts (takes symbol rate, frequency, polarity, FEC etc...not band), so its not something I'm really familiar with. I'm also trying to understand how this relates to diseqc switches, given I never actually specify the band, I'm curious about how the addition of a diseqc invalidates whatever magic happens behind the scenes in the drivers relating to band.

[newyankee]

I haven't found many good descriptions in english. Multiple band and position switching seems to be quite popular in continental Europe and not so much elsewhere.

This is just a start:
Ku-Band allocation

In Europe, because of the massive amount of channels transmitted for direct-to-home systems, Ku DTH satellites use two frequency ranges
10.7 to 11.7 (low) and 11.7 to 12.75 GHz (high). Tuners only have an IF input range of 950 - 2150 MHz. This is only sufficient for one of the two bands listed above. Thus, universal LNBs have been developed. They can receive both bands using two local oscillator frequencies (LOF Low 9.750 GHz, LOF High 10.600 GHz). Using these two frequencies, each band can be individually down-converted and "fitted" into the tuner IF input range of 950 - 2150 MHz. Polarisation is selected using 14/18V, and band using a 22 KHz tone (on/off) to switch bands. These two are so-called analog switching criteria. I have found some additional tech info in english here LNB function.

Universal single LNBs just have one output for a single receiver, so the two switching signals are sufficient. However, for multiple tuner outputs ("multi room") it becomes a little more complicated, and even more for multiple LNB/multiple combinations. For this, we use universal quattro LNBs with four individual outputs (V/lo, H/lo, V/hi, H/hi) and connect one or more of these to a multi-switch which is then fed by the number of STBs or PC-tuners as desired. The manual for a good multiswitch (I have a similar but simpler example) in both german and english (starts on page 12) with many examples can be found here.

I found another quite good description of the diseqc specs here.
An excellent overview of the corresponding diseqc commands are listed in this document.

I hope this answers some of your questions.

Guido

[sub]

Cheers for the info. I think I've made some headway. Can you please try the attached patch?

[newyankee]

Indeed, the patch made quite a difference:

With diseqc off, I have the same behaviour as before: I get the last setting (in this case high band, H polarity only). I have commented into the scan log where it appears that I get V transponders, but in reality they are H.

With diseqc set to "A" I get high band and BOTH polarities (H and V). I can see the corresponding diseqc bytes in the log. Now, the low band is still missing. But if you added F0 for low band/V and F2 for low band/H with tuning requests for frequencies below the LNB switching frequency (11700 in central Europe), everything will work for diseqc "A". Things would be similar for all tuning requests for diseqc "B" (F4 through F7) etc.

I have tried to borrow a DVB-S/diseqc monitor that gives readings of what is really coming of of the tuner card but was unsuccessful. Example1 and 2 and 3. All are around 60€ but the first can apparently only detect 2 positions, the third includes a digital signal meter and a diseqc generator. All show the analog switching criteria as well.

I have attached two sets of logs for you, they should be self explanatory.

Very good work, nearly there - thanks so much!

[sub]

Here is another version to try. Hopefully we'll get there with this one.