C band reception woes

[rrob311]

So I have been fooling around with my portable 12 foot dish for the last few weeks. It is nice that it is mounted on a flatbed trailer. I bought 2 new lnbs for it and centered the feedhorn the best I could. It needs new support cables but I have it rigged for now with rope. I am able to catch the ION feeds on 103w and I also caught the Lesea feeds on 99w. They come in so so at best. I cannot scan in any of the other channels on the satellites. I have been using my handheld analog meter and catch a signal with about 5 satellites in the sky mostly around 100w. I think I caught 72w but caught nothing ITC. I was thinking that with a 12 foot dish that I would catch everything on the lists. Instead it seems that I am only catching the strongest transponders. I am also only catching channels on the horizontal lnb. I have no idea how to adjust the skew with the motor on this. Does anyone on here have any insight on feedhorns with multiple lnbs and how to set them up? I would like to maximize reception with this so I can park it. I am getting discouraged with this dish and want to move on setting up my six footer but I like to take care of one thing at a time. Is there a better receiver for strictly C-band? I have been blind scanning with the Openbox which is the only one that has caught anything. I don't understand how/if the receiver and multiswitch setup switches voltages. Nothing is picking up on the Vertical LNB. I received a polarization control box but I have no instructions and I figured that the dual lnb feedhorn would not need to be switched but then again I am lost with this.

 

[Asket]

There are so many things that could be out of adjustment. Is the trailer stable? Is the dish a potato chip? Are the feed horns centered properly and the focal length set
within good limits. Is the arc tracking accurate?

That is just a few.

 

[rrob311]

There are so many things that could be out of adjustment. Is the trailer stable? Is the dish a potato chip? Are the feed horns centered properly and the focal length set
within good limits. Is the arc tracking accurate?

That is just a few.

The trailer is extremely stable and has jackstands supporting each end. The dish folds apart bolts together so I am pretty sure it is not warped but I should probably check that. I centered the feedhorn the best I could to achieve maximum signal. I am not sure how to set the focal length on this one. I don't see an adjustment. What would the calculation be for a 12 foot dish?

 

[Auric]

The trailer is extremely stable and has jackstands supporting each end. The dish folds apart bolts together so I am pretty sure it is not warped but I should probably check that. I centered the feedhorn the best I could to achieve maximum signal. I am not sure how to set the focal length on this one. I don't see an adjustment. What would the calculation be for a 12 foot dish?

There should be a little set screw, basically you just move the LNB in & out & twist it side to side. There are several adjustments to be made on a C Band dish.
LNB adjustment
Scaler Ring adjustment
Elevation adjustment
Polar adjustment
Azimuth adj
Arc adj
What I do is peak the signal on my southern most sat first. Mine is 93W G25 then I check my Arc by going out to some sats like AMC9 @ 83 to see how RTV is coming in & on the right side of my horizon I'll go to Satmex 6. If everything is working great I got to end of my horizons. If not I go back fix the worst...usually RTV. From that point you need to figure out what needs adjusting...Hopefully just the LNB

 

[FaT Air]

Being it's an unfamiliar dish, I'd start at the top. String it to see if it's warped. Measure it and calculate the focal length. Make sure the feed is centered, and square with the dish face. Focal length and F/D ratio calculations in http://www.satelliteguys.us/c-band-satellite-discussion/222234-bud-manual.html No Vertical, bypass the switches. Wire direct to the lnb. Can't remember, but I think that's on an AZ-EL mount(?)

 

[rrob311]

I found a Wasp/Hornet net in the feedhorn this morning. There is also some debris in there I am going to try and clean out. The dish came with an Avantek AWC-42085 LNB. It has a different connector on it so I am going to try and find an adapter today so I can try this LNB and see if the reception changes. It is made in the USA and it seems like it would probably be more sensitive. I am also going to replace the cables. There doesn't appear to be any adjustment for the depth of the feedhorn.

 

[Auric]

I found a Wasp/Hornet net in the feedhorn this morning. There is also some debris in there I am going to try and clean out. The dish came with an Avantek AWC-42085 LNB. It has a different connector on it so I am going to try and find an adapter today so I can try this LNB and see if the reception changes. It is made in the USA and it seems like it would probably be more sensitive. I am also going to replace the cables. There doesn't appear to be any adjustment for the depth of the feedhorn.

I couldn't find any info on that LNB, but make sure it's not an analog only LNB. There are not many of those channels left

 

[rrob311]

I replaced the suspension cables and cleaned the feedhorn. I now have a slightly better signal. I put my signal meter on the Vertical LNB and when I peak it on 99w I can cover the mouth of the scalar ring and the signal jumps up off the end of the scale. Usually it lowers the signal when I block it with my hand. IDK how to power the motor that controls skew so I am going to try to bypass the motor somehow. Does anyone know how to control these skew motors?

 

[Auric]

I replaced the suspension cables and cleaned the feedhorn. I now have a slightly better signal. I put my signal meter on the Vertical LNB and when I peak it on 99w I can cover the mouth of the scalar ring and the signal jumps up off the end of the scale. Usually it lowers the signal when I block it with my hand. IDK how to power the motor that controls skew so I am going to try to bypass the motor somehow. Does anyone know how to control these skew motors?

You need an IRD or a receiver like a Pansat 3500SD

 

[rrob311]

OK, I got the skew control working. Too bad there is no scale. That polarization control box moves the motor fine. I caught a couple more channels. The ones on the Vertical LNB won't come in but the openbox caught them. For some reason my transponder numbers are off. Sometimes when I shut off the receiver then try it the next day channels won't come in and I have to re scan them and they come in on a higher transponder number. I wonder if it is a problem with the lnb or multiswitch because I tried another reciever and it finds the same numbers that don't correspond with the lists on lyngsat or sathint.

 

[Lone Cloud]

I have had a bit of trouble with my Birdview when the due south position and the apex position was not at the same point. I don't know your dish, but on the BV there is no indicator on it of apex. It's a little bit of trial and error.

Once I've found the apex position I look at my due south satellite. In my case it's about a half a degree east of my dish longitude. Since I know my Birdview has about fifteen clicks per degree, I moved my dish seven clicks east.

I am a total advocate for using "beep on scan" receivers and wireless headphones for aiming. I use an old Viewsat box. Then you set the receiver for the satellite and a hot transponder, make sure the wireless sending unit is powered on, and then move the dish around the pole and up and down until you get the best signal. I have my Birdview set up with a threaded rod adjustment for up and down, so I just turn a crescent wrench until I get the highest pitch and fastest beeps. Usually, I am on it for the entire arc if I dial it in like that.

Apologies if you already know about this aiming method

 

[FaT Air]

try it the next day channels won't come in and I have to re scan them and they come in on a higher transponder

sounds like LO drift in the LNB. Log the freqs, and I think you'll see a trend, BTW: this symptom must be on the LNB that came with the dish?

Does anyone know how to control these skew motors?

I think you have a "one of ?" where there's only one left.

 

[rrob311]

sounds like LO drift in the LNB. Log the freqs, and I think you'll see a trend, BTW: this symptom must be on the LNB that came with the dish? I think you have a "one of ?" where there's only one left.

I bought 2 DMX211 lnbs and put them in. The LNB that came with the dish has a larger connector on it which I don't have the right connectors for.

What causes LNB drift? poor lnbs? Could the Multiswitch I am using cause this or poor cables? What can I use to waterproof my connections outside?

I still cannot pickup my Vertical Transponders. I barely caught a couple but at very low quality. I should have enough time today to experiment with the skew setting now that I finally figured out the motor. Hopefully I can order some coax to replace the stuff that came with the dish.

 

[FaT Air]

Well. being new lnb's,(and all I've read about them is good) the drift kinda has me stumped, other than drift in the receiver(?). Does this receiver do the same on another dish/lnb (Ku?) Don't think drift could be caused by switches,
<<Could the Multiswitch I am using cause this or poor cables?>> Could be. Try wire the receiver directly to one lnb, than the other. Another thing to try is the Orthomode feed, try turn it 90 degrees. that would make the H -V, and the V-H. Then see if the TP's you get reverse polarity. Then. swapping the lnb's around. It may be that the LNB doesn't like 13v. swap the H an V inputs to the switch.(reverse the polarity as seen by the receiver.normally H pol gets 18v, V gets 13) May need to mod the switch or use power inserters. Guess it's a game of eliminating all that could cause the problem, then adding each, one at a time, to see what causes it.

 

[rrob311]

Well. being new lnb's,(and all I've read about them is good) the drift kinda has me stumped, other than drift in the receiver(?). Does this receiver do the same on another dish/lnb (Ku?) Don't think drift could be caused by switches,
<<Could the Multiswitch I am using cause this or poor cables?>> Could be. Try wire the receiver directly to one lnb, than the other. Another thing to try is the Orthomode feed, try turn it 90 degrees. that would make the H -V, and the V-H. Then see if the TP's you get reverse polarity. Then. swapping the lnb's around. It may be that the LNB doesn't like 13v. swap the H an V inputs to the switch.(reverse the polarity as seen by the receiver.normally H pol gets 18v, V gets 13) May need to mod the switch or use power inserters. Guess it's a game of eliminating all that could cause the problem, then adding each, one at a time, to see what causes it.

I have tried all my receivers and the numbers are all the same so I think it is somewhere else. I will not be able to try a direct cable until I order some. I don't have instructions for the feedhorn but I was not sure how the skew settings would be with H and V. I haven't tried to rotate the feedhorn 180 degrees but I have a hunch this could be affecting the verticals. I am able to get almost 99% quality on the Lesea and Mytv feeds on 99w. I barely caught a couple Vertical channels but they come in and out. I would like to pickup every channel on this bird so I can move to the next one and start checking.

 

[FaT Air]

Rotating the ortho 180 keeps the H lnb on H, and the V LNB on V, By rotating it only 90, the H lnb will pick up V tps, and the V LNB will pick up the H transponders. This may give a clue. As the H LNB gets 18 volts from the switch. The V LNB only gets 13 volts. So then, if turning the feed 90 degrees, the vertical TP's work, but loose the H. It's the voltage to the LNB causing the problem. Follow? May have to use a power inserter in at least one LNB lead.

 

[rrob311]

Ya I'm gonna try that tonight. Can I just run the vertical lnb into the 18v setting on my multiswitch to test it?

 

[FaT Air]

Yep. My thinking is the lnb doesn't work well with only 13v.Hook the 18v lead to the vertical lnb and see if the vertical TP's come in.

 

[Beano_face]

Yep. My thinking is the lnb doesn't work well with only 13v.Hook the 18v lead to the vertical lnb and see if the vertical TP's come in.

exactly... dont both lnb's require 18 volts.?.?.

 

[rrob311]

I tried the work around with the multiswitch but didnt get anything new. I am going to try another satellite here shortly and I will see what comes up. Is anyone able to get the fox puerto rico channel on 99w? Those are the main ones I am trying to get on that bird. But I haven't been able to get anything on that transponder.