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Discussion Starter #1
Houston do we have a problem? I need help from those of you guys that have the Zenith STB. I've noticed that the signal strength on Satellite B, transponder 23 is VERY low. I'm getting a signal strength of about 19, which is rated as "bad" on the signal meter. This transponder seems to correspond (unfortunately) to HBO HD. What makes me think this is a problem with my unit is that both my RCA DTC100 and Sony HD100 both show a normal signal strength of about 75-77 on the SAME incoming satellite line and that same transponder. Other Sat B transponders show decent strength, but not great, on the Zenith (although most are significantly lower than my other receivers on the same transponders) with the exception of one other transponder, 22, which shows a low strength of 35. I'm not sure if that one corresponds with Ch 199. My weather is crystal clear with nothing in the area whatsoever. BTW, Satellite A transponder strength seems fine. I've never seen anything suggesting a mis-alignment of the dish, particularly when my other receivers seem fine (excepting the Sony quirks which we all know about).


Can you guys check your unit's signal stength on the Sat B transponders (particularly 23) for me?
 

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My only thoughts, there is a meteor shower that is going on early morning in not too many hours.


It might be goofing the satellite's floating around out there.
 

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Discussion Starter #3
kebcubed,

The problem with that theory is that at the same time both my other receivers are showing significantly higher signal stengths.
 

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Discussion Starter #5
rhampton,

Yes. Actually used the same satellite line for 3 different receivers (Sony, RCA & Zenith). The Zenith is the only one that's getting these low Sat B readings. Some transponders are O.K. but several, especially 23 are low. I can't figure out how, if a receiver has some type of problem, that it would only manifest itself on a few transponders. Satellite A transponders are fine (you would generally expect higher Sat A signal strength than Sat B), but Sat B is an issue. Very strange.
 

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It appears that some of the transponders on 119 may have inherently stronger signals than others (due to some satellite problem?). Following are my readings this morning for transponders 22-32 on the 119 satellite. For reference the average signal strength I'm getting on the 101 satellite is 94 with a range from 91 to 97 (less variability in strength than 119).


22: 78

23: 67

24: 74

25: 59

26: 78

27: 73

28: 78

29: 73

30: 80

31: 80

32: 78


Perhaps your satellite dish isn't properly aligned to optimize the strength for the two satellites.


- Scott in Chicago


EDIT: Should have noted that this is using a Hughes E86 receiver....
 

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Ken,


Looks like 22 and 23 are lower. Here are mine:


Sat A: Trans 1 = 96


Sat B:


22=75

23=67

24=93

25=80

26=84

27=80

29=91

30=86

31=91

32=94
 

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I'm not sure why this would manifest itself on only few transponders, but supposedly every satellite that was able to be moved had their profiles minimized towards Leo, to avoid become expensive garbage from a meteor hit. In 1993 one satellite did become toast from one of the Leonid hits, so I'm sure everyone was wary. Perhaps their solar cells had decreased output by being turned and transmitting power was decreased, or who knows what, but it's a thought.


I wonder what it felt like to the astronauts on the ISS with all that debris coming their way. I know there's lots of space, but that's a pretty big target.
 

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Ken, I just checked all mine on 119 and Transponder 23 was the lowest at 74, the rest were high 70's to low 80's, so I am not seeing a problem here.


I hoping that maybe the Zenith is giving you better information on your dish not being aligned perfect.


Let me know if you want me to check something else.


George
 

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Is the OTA recption any better then the others STB's ?
 

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Discussion Starter #11
Thanks Scott, Steve & George for the readings.


Steve & George,

I'm encouraged that you guys have what I would consider to be normal readings on those 2 transponders with the Zenith. It means at the least there is no design problem with the Zenith. However, I'm really beginning to wonder if my unit is defective. The fact that I am getting such low readings (19 & 35 on transponders 23 & 22) on the Zenith when my other STBs hooked up to the same line are getting readings similar to what you guys are getting (in the 70s), makes me think I have a problem with my unit. I just can understand why these 2 transponders register so low. You would think if the unit is defective ALL transponders would be very low.
 

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 :) Since we are dealing with RF here, and RF is FM most of the time, one thing you might try is a different port and cable. Possibly the cable was kinked at one time or has a bad connector. The 1080 might just have a different input impedance which is causing a hole to move to a bad place (23). I have seen stranger things in my RF travels. Just a thought. :)
 

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Discussion Starter #13
Joe,

Good thought except I brought the Zenith upstairs to where my Panny Tau is situated. Here there is a different line running to my Sony HD100. With the Zenith hooked up here, I get exactly the same readings of 19 on transponder 23 and 30-35 on transponder 22. These are 2 independent lines coming from the dish. Downstairs where the Zenith would normally be situated (and previously the RCA DTC100 running at 1080i) I get the same low numbers. Keep in mind that the other 2 receivers are getting normal readings whether upstairs or downstairs. Only the Zenith is getting these abnormally low values. Something is up. I think I've eliminated all the variables.
 

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Ken,


I'm not sure if my hypothesis is feasible. However, I'm thinking that it might be possible for different brands and models of DIRECTV receivers to have slightly different optimal dish orientation pointing. Based on what you've already stated, this is the only other variable I could think that you could rule out absent a defective DTV1080. That being said, if you are receiving relatively high signal readings on all other transponders except 23 and 25, I doubt my theory is possible. However, didn't you say that your are getting significantly lower signal strength on all transponders on the Zenith? If this is the case, you might want to try slightly re-orienting your dish (if its easily accessible).


I have firsthand experience with certain very low signal transponders (30s and 40s). However, all other transponders on this older RCA receiver were also low, in the 50s, 60s and 70s. I isolated the problem as being too much signal blockage from trees. After re-locating the dish from my back to side yard, my signal strength went up to the 70s and 80s on all transponders, with my low strength transponders still being the weakest. Therefore, it might be advisable for you to try tweaking your dish before conclusively conceding your DTV1080 is defective. Then again, I could be wrong about this entire theory. Technically, it seems illogical that optimal dish orientation would be much different for different receivers. Especially, since a very minimal adjustment in the azimuth, elevation or tilt of your dish can make a huge difference in signal strength. I hope you solve this problem soon one way or another because I know how long you waited for your DTV1080.


Andrew
 

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Discussion Starter #15
Andrew,

Unfortunately it's not easy reorienting the dish since it's on my roof (I had it professionally installed). I tend to doubt that the aiming would be different from one receiver to the next especially when you consider that both the RCA & Sony HD STBs are showing approximately the same relatively high signal strengths (70s & 80s) on just about all transponders on Sat B using exactly the same wiring. It's only the Zenith that's showing significantly lower signals. For whatever reason transponders 22 & 23 are the real bad ones on the Zenith at about 19-20. Transponder 22 is worse today than yesterday. These 2 transponders are not the weakest on either the Sony or RCA HD STBs. I am getting signals of upper 70s to low 80s on these transponders on the other units.


Interestingly, the relative difference between transponders 22 & 23 and all the others on Sat B is MUCH greater on the Zenith than either the RCA or the Sony. The other transponders on Sat B on the Zenith register a strength of 50s, 60s or 80s. Transponders 31 & 32 are in the 80s on the Zenith, yet drop to 19 on transponders 22 & 23.


My concern is that I have close to zero leeway for any kind of bad weather. With this kind of signal strength I'm afraid a heavy overcast will kill the picture on channels 199 & 509.
 

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If you only have a signal of 19 to 20, I'm surprised you are getting a picture. At minimum you should be having pixelization or brief drop outs. Maybe the signal is really o.k. but the meter is reading it wrong.
 

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Discussion Starter #17
Steve,

That's EXACTLY one of the two scenerios I was thinking. Either the signal meter is inaccurate on Sat B since Sat A readings seems well within what my other two receivers are getting or the meter is accurate and the unit is very close to the threshold for picture loss. A light shower or heavy overcast might be all that's necessary to cross the threshold. I have no idea how these STBs are constructed and whether or not there are two seperate internal receivers (one for A & one for B). It's the disparity in measured signal strength that's really strange. Although all Sat B readings are lower than my other two receivers, the radical drop on transponders 22 & 23 compared to the other readings on the Zenith are really odd. If it is the signal meter, why such a difference on those two transponders compared to the others?


Otherwise I love this unit.
 

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Ooh, ooh (for those of you old enough to remember that TV show - hint sweathogs :) ). I can answer this :) The Sat receiver does not do the A/B or the polarization. The multiswitch does. All odd channels are one polarization, evens are the other. In fact my HD-100 has all the odds 10 "units" down from the even on the 199 sat (not uncommon I think). A voltage and/or 22 KHz signal select which one you want for that set (2 voltage levels and 22 or not). This was what led all of us hopeless HD100 users to understand what was causing the hourly dropout (I put a scope on mine). If all of your Odd 199 channels were low, I would suspect the LNB or the mutiswitch - or even maybe the adjustment of the antenna. Since 22 and 23 are both low, that unfortunately means that's not the problem :( So, I have now provided no help at all :)
 

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Discussion Starter #20
O.K. guys I've isolated the problem! It IS a bad signal meter. This morning we had rain in the N.Y. area and my signal meter was reading ZERO on HBO HD and HD Net. Not so amazing except for the fact that I had a PERFECT picture! So obviously the weather wasn't bad enough to actually lose the signal but the Zenith signal strength meter thought I did (it just didn't tell the receiver that). BTW, my other receivers were reading about 70 on these channels.


I'm swapping the unit out since you do need to know your signal stength accurately. Interestingly, the Zenith meter is fine on Satellite A. Go figure.
 
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