Ku for DSR922

[Geo Desik]

Does anyone use or recommend a Ku LNB that works well with the DSR922? I currently have the Astrotel Precision model PMJ-LNB KU, it’s rated 0.5 dB. It worked with my old analog IRD but I haven’t been able to view anything from Ku satellites on either of my two DSR922s (one Motorola, one General Instruments). The C-Band stuff, both analog and digital, looks great.
Ideally, I would be able to just mount the new LNB on my existing feed horn IF they have a standardized mount (do they? My current feed horn is the Astrotel PM-93 C/Ku corotator). Otherwise, I would just replace the whole feed horn with a new C/Ku LNB or LNBF. Does the BSC621 C/KU Band LNBF work good for anyone with a DSR922?
Thanks,
Geo

[wejones]

Originally Posted by Geo Desik

Does anyone use or recommend a Ku LNB that works well with the DSR922? I currently have the Astrotel Precision model PMJ-LNB KU, it’s rated 0.5 dB. It worked with my old analog IRD but I haven’t been able to view anything from Ku satellites on either of my two DSR922s (one Motorola, one General Instruments). The C-Band stuff, both analog and digital, looks great.
Ideally, I would be able to just mount the new LNB on my existing feed horn IF they have a standardized mount (do they? My current feed horn is the Astrotel PM-93 C/Ku corotator). Otherwise, I would just replace the whole feed horn with a new C/Ku LNB or LNBF. Does the BSC621 C/KU Band LNBF work good for anyone with a DSR922?
Thanks,
Geo

If the lnb worked with the analog ird, it should work with a 4dtv. Does it work on analog transponders? I'd really suspect a problem with your coax, or perhaps you don't have the polarity adjusted right on Ku channels. If you still have the analog IRD, can you verify that the lnb still works with it? You might try switching coax between C and Ku to see if coax is the problem. Any consumer lnb should work and fit. Most people seem to like Norsat. Cal-amp and a few other brands are good too. Only one I've had bad experiences with is Eagle Aspen. Worked fine, but only lasted a couple weeks. But there is no reason why your current lnb shouldn't work with a 4dtv if it worked with a regular ird. When digital (DCII and DVB) receivers first came out, there were a lot of people saying that you needed to go out and buy a new digital ready lnb, because supposedly the older LNBs wouldn't be stable enough for digital, however older lnbs worked just fine 99% of the time.

[rainman]

I agree with Bill if the lnb worked before it should work with the digital the quality might not be as good but should work. I upgrade from a astrotel precision lnb to a norsat for better picture quality on dvb.

[Geo Desik]

Thanks for the info! These are good ideas I will certainly try before buying a new LNB. I'll post the results . . .
Geo

[KINGBICHO]

what is the best lnb out there for someone to upgrade?? is norsat the best?? I have a 8.5 mesh dish with feedhorn and dual c/ku band lnb.....i have a hard time locking in some DVB channels.....

[elgemcdlf]

Originally Posted by KINGBICHO

what is the best lnb out there for someone to upgrade?? is norsat the best?? I have a 8.5 mesh dish with feedhorn and dual c/ku band lnb.....i have a hard time locking in some DVB channels.....

lnb will not (unless bad) keep you from locking signal (within reason). Are you having problems with C or Ku? My guess is Ku. The main culprit is usually alignment. Especially on big dish C Band setups. These setups were usually installed with no regard for digital and especially DVB. So to lock a watchable analog C Band signal alignment was not near as critical. I would start by centering the dish and working with alignment to achieve peak signal using the Ku side and the dvb receiver. Now run out to both ends of your viewable arc and further work with alignment. Once you have the system peaked for Ku on the DVB receiver I think you will be surprised as to how much better your C Band viewing is.

Something to keep in mind when playing with alignment. The larger the dish the larger the side lobes. You can be in a side lobe that is so strong you believe you are correctly aligned on a sat. If you find your self having great difficulty aligning the arc try going back to center and raising the dish until you find signal again. You will leave signal and then it will come back. If it never comes back try going in the opposite direction (below where you had signal). If you never find signal above or below you most likely are in the correct spot. If you do find signal one or the other is correct and the other of the two is a side lobe.

[rainman]

Originally Posted by KINGBICHO

what is the best lnb out there for someone to upgrade?? is norsat the best?? I have a 8.5 mesh dish with feedhorn and dual c/ku band lnb.....i have a hard time locking in some DVB channels.....

if you are wanting to upgrade then yes i believe the norsats are the best it increase my signal by 20 points. but has Steve said above alignment is more important get the best signal you can with the lnb that you have then if you want to upgrade you should get a even better signal.

[Geo Desik]

First, I cut off the old F-connectors at the Ku LNB and receiver and replaced them, making sure to polish up the copper conductor for a good contact. That didn’t help. Then I swapped the C and Ku coax cables at the feed horn and receiver and found that they both worked for analog and digital C-band but did not work for analog or digital Ku band (at least I won’t have to bury a new cable!) I have a spare LNB exactly the same as my existing one (but it has never been used before) so I installed that one – no luck there either. So the result is – everything is still the same – no analog or digital Ku but good analog and digital C-band on my DSR922s.
During all this, I did discovered that I could not tune C-band G-11 or T-6, even though I CAN tune W3, which is east of G-11 and T-6, and I CAN tune T-5, which is west of G-11 and T-6. I guess I’ll recheck my vertical (elevation) alignment and feed horn centering even though I have checked these recently. Something may have slipped.
Thanks to wejones, rainman and elgemcdlf for all the help and advice!
Geo

[elgemcdlf]

Ok reverting to the obvious. Did you tell the receiver you have Ku? I mean physically standing in front of it and saying "we now have Ku". Just kidding but there is in the setup menu an area to let the receiver know what you are running for lnb/lnbf's. Make sure you are setup correctly there.

[wejones]

Originally Posted by Geo Desik

..... Then I swapped the C and Ku coax cables at the feed horn and receiver and found that they both worked for analog and digital C-band but did not work for analog or digital Ku band ....

Did you try running the C-band coax into the Ku input on your receiver, and visa-versa ??? I was just thinking that perhaps there was a problem with the receiver's band switching. Ie if you run the C-band cable into the Ku input while on a channel with a lot of analog channels, you should see reversed video analog (although if the channels are VCII it actually might look normal) video when your receiver thinks it is tuning Ku. If you can find a sat with analog on Ku (AMC15 was one I ran across yesterday, ie an Echostar slate), then the same should happen when the receiver thinks it's tuning C-band. If you have a digital voltmeter, I'd also try checking the coax for voltage where it goes into the two lnbs. If you don't have a voltmeter, one of those little SF95 meters should squeal if there is voltage, although you'll have to turn the knob up.
These 3 tests should tell you what component is at fault.

[KINGBICHO]

I dont have a problem locking in the KU DVB channels.....especially the ones with a high SR number....the problem I have is locking in the low SR number DVB channels like C-Band channels....Especially the SatMex 6 spanish channels in c-band......the KU side of the satellite works good....so is it still alingment or lnb/coax problem??

[Geo Desik]

elgemcdlf : Yes, I set up my DSR922 for "C and Ku band LNBs" ( I have a servo to set the skew on the feed horn ) The 4DTV units only display the satellites that you have selected for on the "move to" or "program" screens: in other words, if I hadn't told the receiver I was looking for Ku, it wouldn't show me that they are there.

wejones : Yes, I switched the C and Ku coax to make sure they both were ok. I did that AFTER I hooked up a new coax to the Ku LNB ( which did not help either ) but I wanted to make sure that coax I was using for the Ku is ok. Both do great on C-band analog and digital but neither lets me tune Ku analog or digital.

KINGBICHO : I now think my problem could be bad alignment on the vertical (elevation) of my dish ( a 7 footer, by the way) or possibly, with the centering of my feed horn. I'm going to diddle with these adjustments next, you know, when I get TIME ;-)

In the mean time, I installed a different (spare) decypher module in my receiver and had my provider rehit me with both the new and correct Unit IDs - no change though - still no Ku or G11 or T6.

[wejones]

Originally Posted by Geo Desik

wejones : Yes, I switched the C and Ku coax to make sure they both were ok. I did that AFTER I hooked up a new coax to the Ku LNB ( which did not help either ) but I wanted to make sure that coax I was using for the Ku is ok. Both do great on C-band analog and digital but neither lets me tune Ku analog or digital.

I understood you to say that you completely switched C and Ku coax, ie I think you switched both at the receiver and at the feedhorn. What I was suggesting was to only change at one end, ie have your C-band lnb connected to the Ku input of the receiver, and visa-versa. Ie this should test the switch in the receiver when in Ku mode, and can also test whether the receiver is putting out lnb voltage in Ku mode.

[Geo Desik]

wejones: What you were telling me finally soaked in - I'll check out available voltages from my receiver and at the feed horn for each band when I start my centering and dish elevation adjustments. Thanks!
Geo

[elgemcdlf]

Originally Posted by Geo Desik

elgemcdlf : Yes, I set up my DSR922 for "C and Ku band LNBs" ( I have a servo to set the skew on the feed horn ) The 4DTV units only display the satellites that you have selected for on the "move to" or "program" screens: in other words, if I hadn't told the receiver I was looking for Ku, it wouldn't show me that they are there.

The 922 will not show any sat that is not programmed in position regardless of what lnb types or sat type (designator). I have also found sometimes it is required you be set to a C Band designator for C Band DVB and Ku for Ku DVB. Not always and there really seems to be no rhyme or reason.

Let's just back out a bit. Are you receiving The questionable sats with the 922 on the band you desire? If I remember correctly T6 has porno channels on 1 and 7. You should get a screen that says you are not subbed (unless you are subbed). If you are not getting these screens you are not properly aligned OR you have your skew set incorrectly.

[wejones]

Originally Posted by elgemcdlf

The 922 will not show any sat that is not programmed in position regardless of what lnb types or sat type (designator). I have also found sometimes it is required you be set to a C Band designator for C Band DVB and Ku for Ku DVB. Not always and there really seems to be no rhyme or reason.
.....

This should never be the case, but I can't figure out a reason why it would seem that way. A slaved DVB receiver doesn't care whether an analog receiver is tuned to C band or Ku band. In fact, I keep my analog receiver on C-band all the time, regardless of whether I'm tuning a C or Ku signal on my DVB receivers. The only thing that the 922 should be doing for you is getting you aimed at the correct satellite, and setting the right polarity. The only satellite I can think of where it might require you to be on the proper band is AMC1, which has offset polarity for Ku, so I need to tune the analog receiver to Ku to get the proper polarity.
Anyway, I'm confused at why you would see this behavior. Are there any specific sats that this seems to happen on??? Also, does the 922 save separate sat positions for Ku sats vs C-band sats (some analog receivers do, and some don't)? Perhaps your dish is actually moving when you go from C to Ku even though on the same sat???