Corotor II, LNBF and Azbox Ultra

[Lone Gunman]

Got two dishes. One 10ft Winegard with Corotor II and Norsat C and Ku LNBs. Got a SAMI 7.5ft with a DMX741 LNBF. I also just recently got an AZBox Ultra and have been switching it between the two dishes systems to see how each perform. I've noticed that on the Corotor setup when I set polarity on H and do a scan, I also get the same TP numbers as V?? Got an old Pansat 3500 that I scan with on that Corotor and NEVER had this problem?? When I use the new AZ Ultra on the LNBF SAMI dish setup I don't seem to get the H and V w/same TP numbers but the small dish does drop out some of the Ku stuff I've tried to scan.

So does anyone else have this problem when scanning with an AZ and a Corotor?

 

[LocutusOfBorg]

Got two dishes. One 10ft Winegard with Corotor II and Norsat C and Ku LNBs. Got a SAMI 7.5ft with a DMX741 LNBF. I also just recently got an AZBox Ultra and have been switching it between the two dishes systems to see how each perform. I've noticed that on the Corotor setup when I set polarity on H and do a scan, I also get the same TP numbers as V?? Got an old Pansat 3500 that I scan with on that Corotor and NEVER had this problem?? When I use the new AZ Ultra on the LNBF SAMI dish setup I don't seem to get the H and V w/same TP numbers but the small dish does drop out some of the Ku stuff I've tried to scan.

So does anyone else have this problem when scanning with an AZ and a Corotor?

If I understand your configuration, you have to change the polarity of the corotor with the 4DTV and select H or V polarity in the Ultra blind scan. With the LNBF, the Ultra automatically switches the polarity. I don't know what the deal is with the Pansat but it should've performed the same way in the same system setup.

Anyway, my 4DTV controls the LNBF polarity so I have to do one polarity at a time (my Ultra is "slaved" to the 4DTV). In other words, when the 4DTV is set to a vertical transponder, I have to set the Ultra blind scan to do vertical only, then use the 4DTV to change to the horizontal transponder and then set the Ultra to blind scan horizontal only. Otherwise, the Ultra scans both polarizations automatically (but doesn't actually change the LNBF polarization) and logs the same freqs on both H and V. If the Ultra was controlling the polarization this wouldn't be necessary.

 

[Lone Gunman]

johnny you're doing the same thing I am. When I scan on the Corotor, I select H polarity on my 4DTV receiver to do my first scan but after that scan is finished I cnn look at TPs scanned in my AZ and I get both H and V for the exact same TPs??? Don't have this problem with the LNBF on the SAMI but it doesn't see as many TPs either??

 

[LocutusOfBorg]

johnny you're doing the same thing I am. When I scan on the Corotor, I select H polarity on my 4DTV receiver to do my first scan but after that scan is finished I cnn look at TPs scanned in my AZ and I get both H and V for the exact same TPs??? Don't have this problem with the LNBF on the SAMI but it doesn't see as many TPs either??

Don't know what to tell you. I'm not having the problem that you're describing.

 

[Lone Gunman]

I guess I'm just going to have to switch out that Corotor with another DMX741 to see if that fixes this since it doesn't do it on the SAMI dish. That LNBF has spoiled me anyway as now scanning with the Corotor is a PITA compared to it and I only have to make one blind scan pass rather than two which shortens scan time by 50%. That will be a project for warmer weather though.

 

[Lak7]

You need to change the Corotor's Polarity from H to V, since the AZBox can not control the Corotor's Polarity.

 

[jsattv]

I agree with Lak7's comments and when I Blindscan with my Premium + I do a Separate V and H Blindscan. But what works for me is to set the Corotor's Polarity on my Uniden 9900 to V for the AZbox's Horizontal Blindscan and then set the Uniden 9900 to H Polarity for the Vertical Azbox Blindscan. This has virtually eliminated any duplicate Blindscanned Satellite Channels.

 

[Lak7]

...Uniden 9900 to V for the AZbox's Horizontal Blindscan and then set the Uniden 9900 to H Polarity for the Vertical Azbox Blindscan.

Similar issue with a 4DTV and LNBF, the 4DTV receiver needed "Rotate 90" selected in the LNB Setup Menu.

 

[Lone Gunman]

I realize that I have to change channels to scan the opposite polarity but that doesn't explain why the AZBox Ultra will show me identical TP numbers, one with H and the other with V and the 4DTV receiver is still on the H channel? The Pansat 3500 I have never did this and I did two scans on it also, ie, one H and one V!

 

[Lak7]

....that doesn't explain why the AZBox Ultra will show me identical TP numbers, one with H and the other with V and the 4DTV receiver is still on the H channel?

Because you are not changing polarities with the 4DTV. With a TP locked on the AZBox, flip channels on the 4DTV, does the AZBox lose the Lock?

 

[Cham]

I often have that problem on AMC-1 at 103w. I actually have two satellites saved on my analog receiver at 103, one with normal polarity for C-band and one with "off-skew" polarity for some Ku TPs. If I use the wrong satellite (especially on C-band) I will get dupes of the horizontal transponders when scanning vertical. Could be you need to adjust the skew a bit or your skew motor isn't switching properly, maybe cold weather related?. Mine is working now and it's -27 here tonight... but I installed a new one last summer after it got enlightninged.

Agreed changing to the LNBF sure simplifies the skew issue!
-C.

 

[Lone Gunman]

Thanks -C. I'll check into that when I get time. It was on a Ku bird I think. Will have to look to make sure though.

 

[LocutusOfBorg]

I realize that I have to change channels to scan the opposite polarity but that doesn't explain why the AZBox Ultra will show me identical TP numbers, one with H and the other with V and the 4DTV receiver is still on the H channel? The Pansat 3500 I have never did this and I did two scans on it also, ie, one H and one V!

That will happen if you set the Azbox to blind scan both polarities instead of just one polarity at a time.

 

[LocutusOfBorg]

Because you are not changing polarities with the 4DTV. With a TP locked on the AZBox, flip channels on the 4DTV, does the AZBox lose the Lock?

He has to set the Azbox blind scan to scan only one polarity also. If it's set to scan both polarities the Azbox will log identical transponder freqs with both H and V. Doesn't that make sense to everybody?