C-Band transponder issues

CCRSAT

Well-Known SatelliteGuys Member
Original poster
Dec 28, 2017
31
8
Cedar Rapids
I have an 8' dish with a titanium C2-PLL LNBF, and have been sweeping for certain transponders for about 4 days now. I use 2 satlink meters, and a linkbox 9000i sat box.
I am after CBS feeds from 97W, but the ONLY channels i can get are azteca channels from 3760 and 3813. I have marked the ground to let me know what sat i am near as i rotate, and have them all marked fairly accurately. When i try to adjust for the transponders i get a solid -17 db on my meter but no lock. I can sweep my dish 2 birds either direction, and the signal level only drops to -20 db.
I have ran the strings across the face of the dish and verified it's shaped correctly, and calculated focal depth 3 times.
I am located 1 mile east of an airport, but have 2 other dishes up and locked on birds no issue.
Are the Azteca feeds on a stronger transponder?

I am located in Cedar Rapids Iowa
 
Those CBS feeds on 97w are almost impossible to lock, if you mean the ones on 4080 & 4100.

Even IF you could lock them, they are 4:2:2 and there's NO FTA receiver that can decode them at present.
 
I believe the only way to watch is to stream them from a capable sat receiver to a media player like VLC or save to a file and play them back in something like VLC.
 
The CBS feeds on 97 are 9/10 FEC, I get them "ok" with a 10-footer but it would be a challenge to pick them up reliabally with an 8 ft reflector imho. You need 12-13dB S/N to get a lock, what does your meter show for S/N or C/N readings on that TP?


I have an 8' dish with a titanium C2-PLL LNBF, and have been sweeping for certain transponders for about 4 days now.
I am located in Cedar Rapids Iowa
 
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I don't get s/n on my meter, just the 2 bars showing signal lock. The best i can get after an LNB depth adjustment is 97% and 2%.
I have 6 other dishes on the roof, 3 being for Directv and Dish, and o never have problems locking them in.
For giggles, i tried to lock 103W Ku on my smaller dish, and am not getting more than 88% and 12% on the strongest transponder. Am i fighting airport noise?
 
Finally figured it out. I have my dishes on a metal roof near solar panels. I rebuilt a Ku set up and accidentaly flipped the j-mount which raised the dish 2 1/2 feet. I did a sweep on it from there and locked every channel i went hunting for. I got some extra cinder blocks and raised my 8' dish another 2 feet, and now channels are coming in better. I must just have a noisy roof.
A have a new question, and am pretty sure i know the answer. Using my Titanium C2-PLL, i can now get V or H off of 1 output. I can run a scan while connected to only 1 output and will get signals for both polarities. Running a blind scan, my tuner finds each transponder as V and H with equal signal strength, and will give me duplicate channels. Did in fry my LNB? I really wanted to have V and H on seperated outputs. did i get the wrong one?
 
Finally figured it out. I have my dishes on a metal roof near solar panels. I rebuilt a Ku set up and accidentaly flipped the j-mount which raised the dish 2 1/2 feet. I did a sweep on it from there and locked every channel i went hunting for. I got some extra cinder blocks and raised my 8' dish another 2 feet, and now channels are coming in better. I must just have a noisy roof.
A have a new question, and am pretty sure i know the answer. Using my Titanium C2-PLL, i can now get V or H off of 1 output. I can run a scan while connected to only 1 output and will get signals for both polarities. Running a blind scan, my tuner finds each transponder as V and H with equal signal strength, and will give me duplicate channels. Did in fry my LNB? I really wanted to have V and H on seperated outputs. did i get the wrong one?
on a C2-PLL, each output has both H and V, selected by voltage. If I remember correctly, 13V gives V signals and 18V gives H signals
It is not H on one output and V on the other, but of course with the right voltages it can be used that way.
 
I thought that was the way it worked too, then i opened one of them up and noticed that each one had a different voltage divider off of the regulator. The regulators were identical though.
Still confused as to why i get all transponders as vertical and horizontal with only 1 output being used from the LNB, and I get each channel twice reflecting the same problem. I got a new one today, will swap it out today and see what happens
 
Each output is independent and voltage controlled polarity. My guess is that you are only scanning one polarity twice. Likely a receiver install menu setting.

1. Compare the logged channels found in a blind scan to those on a satellite list like sathint.com. Are the logged channels frequencies matching those on the satellite listing site?

2. Compare the transponder frequencies logged in a blind scan to those on a satellite list like sathint.com . Are the logged transponder frequencies only from one polarity of the satellite TP listing site?

3. What is the receiver's LNB type setting?

4. What is the receiver's LNB LO frequency setting?

5. What is the receiver's LNB voltage (polarity) setting? 13v (vertical), 18v (horizontal), or auto?

6. With the receiver on a vertical transponder, what is the Vdc reading on the LNB IN coax?

7. With the receiver on a horizontal transponder, what is the Vdc reading on the LNB IN coax?
 
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From my Satlink WS-6906 I can run a blind scan right at the dish. I can also see when the meter is switching between 13 and 18 volts. While watching the scan i can see the meter find 4 Horizontal transponders. Then it switches voltages and finds the same transponders but as Vertical. It the finds the same channels again.
LNB type is standard and LO is 5150
LNB power is set to 13/18 volts
I can only assume the voltage is correct as it was identifying everything correctly on my Ku dish and my 6' dish

I guess my questions now are, either output from the LNB can be V or H? and will both work on 13 or 18 volts with out damaging anything?
 
The problem could either be caused by the receiver voltage or the LNBF . The polarity is not switching and the same polarity is scanned twice.

With a multimeter, test the LNB voltage when switching between vertical and horizontal transponders. Vertical transponder voltage should be 13Vdc and horizontal 18Vdc (÷/- 10%). If the vertical voltage is too high or the horizontal too low, the polarity will not switch.

Both ports of the LNBF can be either vertical or horizontal depending on the voltage supplied by a receiver or a switch.
 
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Use the Satlink WS-6906 spectrum display to determine if the carrier fingerprint changes when the STB transponder polarity is changed from horizontal to vertical. If the fingerprint (carrier profile) does not change, the LNBF polarity is not switching. If the fingerprint changes, the LNBF is changing polarities.
 
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I decided to upgrade my equipment a bit, to see if i could get the channels any better.
I bought a GPU server, 2 TBS6909 boards, 1 6908 board, upgraded my LNB to Norsat 8525R and used a BPF-C-1. I am using a power injector for the LNB's so i dont damage the boards or server, and i am using a cheap 2x4 multiswitch.
With this equipment i was able to lock on galaxy 16 transponder 4120 with 98% and 83% intensity and quality on my 6' dish in 10 minutes. I am less than a mile from the airport, and see no radar interference.
I cant watch the video live from the server, but can package it and send it over the network to my PC.

Problem solved
 
4080v plays

I'm locking the 4080 channels with a 91/85 signal on a 10 foot Unimesh. I can get a lock on the 4:2:2 channels on Galaxy 16, but it won't decode them. Thought about streaming them, but not worth the effort to me since I never watch these channels anyway.
 

Are 12' dishes 1-piece? 4-piece?

139W AMC 8

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