Hi guys.I was watching the PBS channels in KU band on AMC21 (125W) for years. Months ago I changed my receiver in order to continue enjoying that programming in its new video format (and also view HD channels). Everything was fine until some 6 weeks ago. Signal was weaken day after day. Only channels I could view were "SD07" and a HD named HD05 (you can see NHK news there). I realigned my 3ft offset dish, changed the LNB, try with different skews and also changed the coaxial cable... Result is the same. Just can detect a weak signal from HD05 (Intensity Signal: 90, Quality Signal varying very fast between 5 and 45). Receiver receives a strong signal from scrambled channels, but not as strong as before (some 50 Quality signal instead of the previous 70).I understand that something has to be wrong with my dish, but I can´t find what it is... Any tips? Greetings...
Problems again catching KU in AMC21 (125W)
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Couldn't guess, since I don't know where you are. Maybe a bigger dish?? I don't pay much attention to pbs on 125-I watch it on 87, or on c-band 103 (or is it 101?) Anyway I usually find something good to watch on one of those channels. It sounds like you've already check everything I would think of, except maybe verifying the pole is still vertical.
If its a fixed dish, then you could even adjust for a slightly leaning pole. If you know your parts are good, the cable is good, and it worked in the past, then I'd think some kind of obstruction is the problem. Do you have any nearby trees that might be growing into monsters that block part of your signal?
If its a fixed dish, then you could even adjust for a slightly leaning pole. If you know your parts are good, the cable is good, and it worked in the past, then I'd think some kind of obstruction is the problem. Do you have any nearby trees that might be growing into monsters that block part of your signal?
Thanks Turbosat.
No trees or towers in front of my dish. It´s in the roof, seeing open sky. I´m in Chihuahua (north of Mexico). I think maybe there is one of three posibilities : LNB holder out of dish focus, a new kind of terrestrial interference, or Transponder signal power did in fact change (don't believe it). I think I will keep on moving dish, LNB holder and LNB itself, and see if signals get better.
No trees or towers in front of my dish. It´s in the roof, seeing open sky. I´m in Chihuahua (north of Mexico). I think maybe there is one of three posibilities : LNB holder out of dish focus, a new kind of terrestrial interference, or Transponder signal power did in fact change (don't believe it). I think I will keep on moving dish, LNB holder and LNB itself, and see if signals get better.
Robotsat, don't you also have a 6 foot dish? I was just wondering what might happen if you temporarily tied on a Ku-band lnb to see if signal improves there 
I used a 2700A Pansat before moving to a HDMicro. This last worked very well with KU-AMC21 for months. Keeps working very well with my other fixed dish : C Band 2.4m pointing to G16.
You are right. I also have a 1.8m C band Dish, wich I turned into a 2.4 diameter adding some plates. It worked great (I want to post a thread with photos about it. I just had no the time for it). My plan is to mount a positioner on this dish to get some other birds. I've heard that a KU LNB won't work with the distance where you mount a C band LNBF, so maybe it would be difficult to catch the KU band. Isn't it like that?
robosat,
I just moved my 31" dish over to 125w. I show 31 channels of which 13 are clear with a Q of about 60.
My STB is an S9 and I'm in Canada near Toronto.
I just moved my 31" dish over to 125w. I show 31 channels of which 13 are clear with a Q of about 60.
My STB is an S9 and I'm in Canada near Toronto.
The F/D of LNBFs made for offset dishes make them see only the center of your prime focus dish.robosat said:
So, to work -best-, try an LNBF like this one:
http://satelliteav.com/p/shop/?ws_pid=665&ws_cat=433
DMSI makes one, too.
And Invacom makes an AF-120 feedhorn that can be mounted on a Ku LNB.
Those are the three solutions I know of for best performance.
If it was working ok in the recent past , and now it doesn't, then you may be on the right track with your mention of a new kind of TI in your area. I wonder how much microwave transmissions are used in your city, and whether or not you might be in the path of a signal. Have you checked by moving the dish to another satellite and trying out correct operation of the receiver that way? The other idea you had, and I haven't read anything about this , that the power levels from the 125 sat have changed. Try finding the footprint of the satellite from the owner and see if you're there!
I've completely lost 125 in the past few weeks, but I think it's a tree branch. I would actually be relieved if there was something else going on, since there's not going to be any chance of removing the suspect branch!
I also had to trim back some branches to optimize 125W. Its a red maple with huge thick leaves. The problem will go away in the fall when the leaves drop.
Signals still nice and strong this morning.
Strange though you mentioned that the problem started after you changed the receiver. Have you tried the old receiver?
Are you going thru switches?
Did you try a direct run of coax from receiver to dish?
Sorry if these questions are basic. Its just that what is happening doesn't make any sense.
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Thanks jorgek. The new HDMicro catched very well AMC21(125W) for several months. Then from one week to another, signal was less and less strong. I always have used just one switch. When moving dish looking for signal optimization, I connect directly the LNB to the receiver (without switch), with me also in the roof, using a 3ft coax cable. By the way, I tried with the older receiver and signal is weak too.
According to Satbeams.com, you should be okay with a 30" dish. Don't know how current the footprint maps are.
Footprint map hasn't change. It is the same that years before. Gonna try with the LNB focus positition and trying to find out about a Possible Terrestrial Interference.
Before anything else, I'd inspect the coax for starters. Look for any discoloration inside the connectors.
Sounds like you had deteriorating signal day after day. Moisture, corrosion.
Then if that's all good. sight along the lower lnb support arm looking for tree branches encroaching.
Check the dish alignment. And the soundness of the mounting. Something could have moved.
If non of that cures it, try another LNBF.
?
Sounds like you had deteriorating signal day after day. Moisture, corrosion.
Then if that's all good. sight along the lower lnb support arm looking for tree branches encroaching.
Check the dish alignment. And the soundness of the mounting. Something could have moved.
If non of that cures it, try another LNBF.
?
Thanks FatAir. I've done all that. Today I just changed the disk mounting 1 meter from its original place. I don´t know why (I know you will think dish was missaligned), but signal got better. Not as before (70 Quality Signal), but I get some 35 now. Weak channels like VME, CREATE and WORLD shows some image, but with a poor Quality of 5-20, and Micro HD can't lock them. The only thing different in the horizon is that a tall building is under construction in more or less AMC21 direction (maybe a mile away from my house), but ATTENTION: it is really down from satellite arc. What I remember now is that when another building was under construction (besides the new one ), I have also this kind of problems with AMC21 signals (I though then problem was my old 2700A Pansat). When that building was finished, my signal recovered strength some weeks after. In both cases of construction, a really big crane was on te roof of building. Maybe that produces some kind of Satellite interference (I REPEAT: Satellite Arc is maybe 30 degrees abobe the buildings from my house).
Regards and thanks for your comments...
Regards and thanks for your comments...
I doubt it would be the crane, it'd have to be one hell of a building & crane to interfere from that distance. Remember the dish is looking 22degrees higher than what it appears. Have you tried over on 123 to see if the problem exists there?
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