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Discussion Starter #1
Hey, I tried searching for what I'm having problems with but I didn't see any posts that were similiar. If I overlooked the results or didn't search properly please redirect me.


I have a Rear Projection LCD TV (SONY KDF-E50A10). It's a very good TV, and I am happy with it.


I recently hooked up a box so I could receieve the digital channels that my parents get on their existing service. At first I couldn't get all the channels because my cable was too old.
It was no suprise to me that the cable in the wall was old, I thought thats what explained the terrible picture quality on regular cable. (Aparantly the digital signals use a newer cable called RG6) So I bought a 50ft RG6 cable from monoprice. I was expecting a clear digital signal on my tv, but I get a static dull picture that looks no better than my original regular cable that I had.


Is it possible that I bought a cheap cable? Is it because my TV is too big? Is the cable too long? My CRT TV upstairs looks crisp and clear and my new cable is plugged into the same splitter. What could be the problem, I can't post links yet.


I bought


RG6 F Type Quad Shielded Coaxial 18AWG CL2 Rated 75Ohm Cable - 50ft


Thanks in advance for any help.
 

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Quote:
Originally Posted by bubsmixtapes /forum/post/12937433


...I have a Rear Projection LCD TV (SONY KDF-E50A10)....

I recently hooked up a box so I could receieve the digital channels that my parents get on their existing service.....

Digital cable does not necessarily mean HD. Call your cable company and get an HD capable box. Standard def cable, even digital, will get upconverted by the Tv to the native resolution of the Tv, which will look bad.


If you hook up the box with coax into the Tv tuner, that is the worst quality connection. It's better to use composite (yellow, white, red) into a Tv input. For an HD box it's best to use component (green, red, blue) or HDMI.
 

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Discussion Starter #3
The cable doesn't go straight into the tv, it is connected by composite cables. I don't expect HD, but I can honestly coun't the pixels.
 

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My setup that works like a dream is this: wall outlet feeds a 15dB broadband amplifier (supplied by Comcast for free), the amplifier feeds a 30-ft cable going to the Comcast DVR, DCT3416, the DVR feeds my set, LNT4042, through an HDMI port.


The amplifier assures that a "weak" signal is no longer an issue. The DCT3416, as a totally digital receiver, eliminates all the analog channels. HDMI, being the best way to connect any source to a TV set completes the best-of-everything list. I would recommend it even if you currently do not subscribe to the HD service or, by choice, watch only non-HD channels.


The exact opposite of this setup, and the worst, is feeding analog channels directly to the set by a wall-to-set cable.
 

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A 50' RG6 quad shield cable with decent connectors should be more than capable of carrying the signal.


I would check any splitters in the path, in particular where the cable enters the home. I've seen problems like you've described caused by a splitter not having the necessary bandwidth or going bad. You can get a splitter than can do the more than 1GHz frequencies at Home Depot/Lowes, etc. for less than $10.
 

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Discussion Starter #7
I just checked my splitter. It says


5-1000MHz

120dB Isolation


Its a 3 way splitter and it has (2) 7dB outs and (1) 3.5dB out.


Is this the problem, (keep in mind it looks very clear on the tv upstairs)
 

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1000MHz = 1GHz so you've got a splitter that should have sufficient bandwidth, but that doesn't mean its not going bad.


The output ratings (7db, 3.5db) are actually the amount of signal loss on that output. By splitting the signal you're reducing the signal by some amount going to each output. The way your splitter is designed it's doing a cascading split (each split reduces the signal by 3.5 db). 1st split gives 2 - 3.5 db loss outputs. Split one of those and you get 2 7.0 db loss outputs.


First try connect at the 3.5 db output. If your picture improves then it's either the inwall wiring or a weak signal. You can buy a suitable amplifier for less than $20 if it's just a weak signal. If it's the inwall wiring you'll have to figure a way to bypass it.


If that doesn't help try connecting directly to the cable coming into the house (you'll need a coupler for that) bypassing splitters and everything else just to make sure it's not your STB/TV setup. If this doesn't help then it's the STB or the cables going to the TV.
 

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If you are using a composite cable(yellow RCA connector) from the STB to your TV then you are watching all programs in 480i which is why you can see the pixels since they are just being duplicated to upscale the video to your TVs native resolution which I believe is 1080p. this would mean that only 1/4 of the pixels actually contain unique information and the others are duplicated or invented content from the origional content.

If you meant that you are using component cables( r,g,b) RCA connectors you also need to understant althoug all HD TV signals are digital not all digital signals are HD. You have to make sure that you are selectint the HD channels from STB and not the standard definition channels (2,4,5,6,7, etc)
 

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Quote:
Originally Posted by bk /forum/post/12940997


1000MHz = 1GHz so you've got a splitter that should have sufficient bandwidth, but that doesn't mean its not going bad.

I see cable splitters at Home Depot and Lowes sold as "digital" and having bandwidth up to 2300Mhz. Any point in getting one of these?
 

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In the past 1GHz splitters were sufficient for most cable TV systems, and the satellite systems required splitter capable of higher bandwidth. Than being said, you can count on cable systems continuing to increase their bandwidth requirements and if the cost of the higher bandwidth splitter is not excessive I'd go that route.


I think the 'digital' is simply marketing although it would be useful as a guide to people who aren't sure what to get and know that they have a "digital" cable or "digital" satellite. In the end you might as well buy components such as splitters, connectors, cables, etc with excess capacity if you can afford them to avoid/postpone wholesale and possibly expensive retrofits down the road. Imagine if your house was wired with RG-59 coax back in the day to save money over RG6, and now needs to be completely rewired with RG6 in order to support current generation cable/satellite signals.
 

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Sometime even good splitters go bad. Why not go to your cable company and ask for a new splitter. In my area the give it free.


On other comment. If you have an outside connection - (grounding block), sometimes the cable/connectors deteriorate enough because of moisture to cause signal problems on some sets (based upon the quality of thee sets tuner).
 
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