OTHER Help with SES-3 103W Ku

[Rod V]

We rebroadcast DW-TV (we have a license agreement) for our college cable channel, and they are switching from C to Ku soon and I can’t find the channel. I’m using a $29 special from Amazon, KOQIT FTA HD DVB S2 Digital Satellite TV Receiver.
With the C-band connected I get all FTA channels including DW-TV. When I do a scan with Ku, it lists several scrambled channels, a few SRV channels that I can view, NHK, CGTN, and few others, but no DW or other FTA channels, and it doesn’t show any channel names. And what is SRV? Please help this confused person, thanks.

 

[cyberham]

The DW channel scans in as "DW English HD" on 12080 H 29970. Its signal is weaker than NHK.

 

[Jim S.]

Are you not getting the NBC network feeds? If so, either your aim isn't good enough or your receiver or LNB is junk.

 

[Rod V]

The DW channel scans in as "DW English HD" on 12080 H 29970. Its signal is weaker than NHK.

Thanks for checking. I forgot to mention that the signal strength is 70, and the quality is 49. I know that's low, but I received the other channels so I thought it was okay. Do you think low signal is the problem?

 

[clucas]

You know that C-Band DW and Ku NHK, etc. are vertical. Maybe you need to change the polarity to horizontal for DW. It could be that simple.

 

[cyberham]

If you are receiving DW with Signal Quality of 49%, you may not see a picture. I am monitoring it now and it is fine. You may need to orient your dish better or get a larger dish. How strong is NHK/CGTN?

 

[Rod V]

You know that C-Band DW and Ku NHK, etc. are vertical. Maybe you need to change the polarity to horizontal for DW. It could be that simple.

Yes, I know. But I could swear that some of the channels I watched were horizontal.

 

[Rod V]

If you are receiving DW with Signal Quality of 49%, you may not see a picture. I am monitoring it now and it is fine. You may need to orient your dish better or get a larger dish. How strong is NHK/CGTN?

I'll check that in the morning. Also, these are large antennas . See attached

 

[cyberham]

They may be large C-band dishes, but that doesn't mean they are tuned to receive Ku well. On my 1.2m Ku dish, I am receiving DW with SQ 70% and NHK with 91%.

 

[Rod V]

Are you not getting the NBC network feeds? If so, either your aim isn't good enough or your receiver or LNB is junk.

No NBC, or Cozy. The only channels are the SRV things. I know the receivers are cheap, but that's all I can afford until next budget year. The LNB is probably 10 years? I used to run Scientific Atlanta receivers when we received SD channels. When the providers switched to HD, the cost of new receivers was a little too much for current budget.

 

[Rod V]

They may be large C-band dishes, but that doesn't mean they are tuned to receive Ku well. On my 1.2m Ku dish, I am receiving DW with SQ 70% and NHK with 91%.

I didn't know there was such a difference between C-band and Ku. I just looked at the coverage map from DW, the C-band has a much larger footprint than the Ku. I'm going to do some tuning on the dish soo,

 

[Brct203]

well, we can't compare quality ratings between receivers... the same signal might display 80% on one box and 40% on another. So it's hard to tell if the problem is weak signal or polarization. There are 2 factors at play here. We know from experience that on SES3 Ku, the H channels are usually weaker than the V channels, so if the dish is not well aligned, that might be enough to make a difference and limit the reception to the V channels. But the other factor, as pointed out by clucas above, is that it could simply be that your Ku setup is working only for Vertical and not for Horizontal. Looks like you're using a corotor feedhorn (or equivalent). But what do you use to control the servo on the corotor? Modern receivers no longer have the ability to drive that stuff... So could it be that you're only receiving what your feed is set to, which would be Vertical (based on what you described, like NHK and DW in C-Band)

 

[Rod V]

well, we can't compare quality ratings between receivers... the same signal might display 80% on one box and 40% on another. So it's hard to tell if the problem is weak signal or polarization. There are 2 factors at play here. We know from experience that on SES3 Ku, the H channels are usually weaker than the V channels, so if the dish is not well aligned, that might be enough to make a difference and limit the reception to the V channels. But the other factor, as pointed out by clucas above, is that it could simply be that your Ku setup is working only for Vertical and not for Horizontal. Looks like you're using a corotor feedhorn (or equivalent). But what do you use to control the servo on the corotor? Modern receivers no longer have the ability to drive that stuff... So could it be that you're only receiving what your feed is set to, which would be Vertical (based on what you described, like NHK and DW in C-Band)

I'm almost certain the problem is polarization. Our current setup is just the receiver-we set the channel and forget it. This is the first time in more than 8 years that I have had to change polarity. The channels have moved, but they were always vertical. In the past, I used an Antenna Concepts positioner with the polarity selector to change between H/V.

So Today, I connected the old Antenna Concepts positioner to the polarotor and pressed the button... and nothing. I checked the voltage from the controller and I have a constant 5 volts. Should there be constant voltage or only when the button is pressed? Can I check the polar rotor with an ohm meter?

Can you or someone recommend an inexpensive controller for antenna position and H/V polarization?
Thanks.

 

[Brct203]

there's a real possibility that the servo (the rectangular blue box) on that feed no longer works, or the probe is stuck. Unfortunately it does not look like it's easy to reach. Also the risk is that if it's stuck, it might have broken when trying to turn. You might need to get a ladder and a screwdriver and check it. Star by removing the feed cover, to expose the probe, and look at it while someone changes the polarity on the controller, and see if it turns (a small mirror makes this a bit easier)

As far as electrical signal, there should be 3 wires: 0V(ground), 5V permanent, and pulse (I think that's the white wire). The way the servo works is that it reacts to the pulses, and its position is proportional to the width of the pulse (i think it's also called duty cycle?). This can be easily checked if you have an oscilloscope. The 5V and the pulses should be there permanently.

As far as controlling this servo, you can either build a small circuit with a timer like a 555, and control it manually. Or you can get more sophisticated and build a circuit that will detect the voltage that your receiver sends to the LNB and use it to control the previous circuit, which would make it automatic. Rick Satellite sells something like that, but it's out of stock. Last but not least, you can try to find an old receiver/positionner (usually from the analog days) and use that to control the dish position and the servo. Of course that also means it's not automatic. Of course the ideal solution would be an ASC-1 from Titanium, but it got discontinued recently and it would have dented your limited budget a bit. So for now maybe stick with your antenna concept controller as least until you figure out what's wrong.

Another option is to completely replace that old feedhorn with an LNBF. But that's something I would recommend only for C-Band. I would not recommend a C/Ku combo LNBF.

 

[clucas]

Are you only looking for DW on 103? If so, loosen the feedhorn from the scaler and give it a 1/4 of a turn and tighten again. You should have a signal.
If you are using 103 for other feeds then you can work on the servo as mentioned above.
Final options are to use one of the other dishes and buy a Ku LNBF, they are not that expensive, and attach it to the side of the scaler. This involves some handywork and patience trying to get it positioned correctly. The easier solution is to take that new Ku LNBF and attach it to a stand alone Ku dish. Check craigslist to see if there are any used free or cheap dishes in your area ideally about 1 meter although a smaller might work- but not a Dish or Direct. They are too small.

 

[FTA4PA]

I'm almost certain the problem is polarization. Our current setup is just the receiver-we set the channel and forget it. This is the first time in more than 8 years that I have had to change polarity. The channels have moved, but they were always vertical. In the past, I used an Antenna Concepts positioner with the polarity selector to change between H/V.

So Today, I connected the old Antenna Concepts positioner to the polarotor and pressed the button... and nothing. I checked the voltage from the controller and I have a constant 5 volts. Should there be constant voltage or only when the button is pressed? Can I check the polar rotor with an ohm meter?

Can you or someone recommend an inexpensive controller for antenna position and H/V polarization?
Thanks.

If you can get to the servo and it is bad you can get a replacement here.

https://hypermegasat.com/all-products/ols/products/universal-servo-motor-polarizer-for-bud-lnb-skew-control

 

[Comptech]

I have plenty of corotors and a couple brand new servo motors. Let me know if either of them are the problem and just pay shipping and they are yours.

 

[Rod V]

If you can get to the servo and it is bad you can get a replacement here.

https://hypermegasat.com/all-products/ols/products/universal-servo-motor-polarizer-for-bud-lnb-skew-control

Thanks for the link. I'll order a couple just in case...

Here's the latest. I did what Clucas suggested, rotated the feedhorn 1/4 turn.
I left the focal length at 40 - the other antennas like they are closer to 30 or 20.
I checked the signal level and it jumped from the low 70's to 84, and signal quality is 74, up from 49. I rescanned the channels and now I have Ch 11 NBC Mountain, Ch 12 NBC West, Ch 15 Occasional, and Cozi TV, but no DW! I rescanned the channels a couple of times hoping it would "magically appear" but nothing.

Do you think I'm close and need to do a little fine tuning?
thanks.

 

[Rod V]

I have plenty of corotors and a couple brand new servo motors. Let me know if either of them are the problem and just pay shipping and they are yours.

Wow! thanks for the offer, I'll be in touch.

 

[FTA4PA]

Thanks for the link. I'll order a couple just in case...

Here's the latest. I did what Clucas suggested, rotated the feedhorn 1/4 turn.
I left the focal length at 40 - the other antennas like they are closer to 30 or 20.
I checked the signal level and it jumped from the low 70's to 84, and signal quality is 74, up from 49. I rescanned the channels and now I have Ch 11 NBC Mountain, Ch 12 NBC West, Ch 15 Occasional, and Cozi TV, but no DW! I rescanned the channels a couple of times hoping it would "magically appear" but nothing.

Do you think I'm close and need to do a little fine tuning?
thanks.

Definitely making progress! Worth it to try a little more fine tuning - you can always go back to where you were if there is no improvement. Just mark everything before so you can return there.