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Discussion Starter #1
Hello and thanks in advance Ok I have Comcast for internet and HD cable. With the HDtv I don't have the best picture on some channels, some look ok and some look great. the other tvs in the house are just digital not HD and and alot of the time the give weak signals freezing for a quick second or two or black blocks. If some one can tell me if a booster will help or not would be much appreciated. Here is the info from my modem if this helps. Downstream

Freq/Power: 723.000 MHz 1 dBmV

Signal to Noise Ratio: 37 dB/Upstream

Freq/Power: 31.600 MHz 51 dBmV

Oh yeah one last question will the booster increase picture quality for the channels that look dull?
 

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Discussion Starter #3
I have 4 tvs one down stairs three upstairs one is HD and 3 computers all on the upstairs floor. The tvs all have their own cables coming from the wall. I don't know if they all connect some play in the house. The computers all run from the same cable. The HD tv has a splitter right before it so the internet can go to the modem.
 

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You have 4 TV's and 3 PC's.

Do you experience the problem on all of the sets?

Did the video ever look good (no breakups)?

Are you using 3 seperate modems or one modem with a wired or wireless set up?

If multiple modems check the diagnostic pages of each.

Which STB do you have, if it is a Motorola I should be able to guide you to access the diagnostic screen for it. (if Moto give the model number).


This can come down to a poor signal level or quality, if it is a level issue an amp should help if it is a
 

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An amplifier will probably just magnify the issue. Really need a decent tech that has a SLM that can measure MER/BER on the EIA channels that correlate with the display channels you are having issues with. As for the amplifier/booster helping the quality of the picture, if you are experiencing poor picture on sets w/boxes--that might be beyond the control of even the cable company. Sometimes, it's garbage in, garbage out. The catch is if it's over compression, then that’s a whole new ball game. If you are experiencing poor pic quality on direct to set, that should be an easy fix for a tech--especially since you are experiencing it on all sets. Troubleshooting is no more than divide & conquer. You are half way there--it's either in the ground block, drop, or off the plant. Hope this helps!
 

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Discussion Starter #6
Mostly the problem is with the nonHD boxes. The HD box work pretty good but some channels on there just don't look right. Yes the video does look good at times. I'm using one modem and it is wired. I'm sorry I don't know what STB.
 

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This is just basic theory and applies to cable as well as RF(rooftop antenna, FM radio, etc): You need to boost closer to the input end of things. That is, if A where where a signal is received or comes into a house and B is where you will be watching it, then the amplification should be done as close to A is is practical. If your car antenna on the rear of the car, you need to run power back there and stick a signal amp inline right after the antenna. Otherwise all you're doing is amplifying sparkplug and any other noises present in the car.


Given, say, a 50 - 75' domestic run of coax, you'd want to amplify the signal no more than 20 feet in from the drop - 10 feet even! Then do your splitting right after the boost point. I personally made the mistake of sticking an FM amp between 40 feet of RG-59(was using my parents' unused TV antenna for FM years ago) and the back of the tuner. Didn't do a damn thing except eat electricity & drain my wallet.



Should've stuck the amp up in the attic, but had no outlets up there.


As for cable box installations, shouldn't need boosters or attenuators, unless you have only family cable with no boxes, just straight into the TVs. Case in point: My family cable service was so HOT I needed to throw -6dB attenuation in there - freebie from Cablevision!! All the mid-upper IRE whites blended together like a klieg light until I attenuated it. But when I got my 4250HD in the livingroom, off came that attenuator. And as mudshvel said, signal boosting will not help it if the station carried by the cable company decides to air shows at a color temperature of 4000K or 10000K!
Or if the interference is between the upfeed & the satellite, or between the sat. and the downlink(cable co.)


A cable box is more than just a channel switcher - it's a sig.amp/attenuator/phase corrector/you-name-it, too, and should be able to do its job without any add ons.
 

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Try this.

To access the diagnostics menu and check the firmware version:


You can run the base platform software or Thin Client software to access the DCT* diagnostics.


To access diagnostics:


1 Ensure the DCT* is installed with the base platform or Thin Client software and that it is connected to an ac outlet.


2 Press POWER and then immediately press SELECT.


The DIAGNOSTICS main menu is displayed on the OSD and d01 is displayed on the front-panel LED. The DCT* is now in diagnostic mode.


This will show you power level and SNR = Signal to noise ratio (very important)

There will be other parameters, let me know what you read about these.
 

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Discussion Starter #11

Quote:
Originally Posted by RCbridge /forum/post/14250733


Try this.

To access the diagnostics menu and check the firmware version:


You can run the base platform software or Thin Client software to access the DCT* diagnostics.


To access diagnostics:


1 Ensure the DCT* is installed with the base platform or Thin Client software and that it is connected to an ac outlet.


2 Press POWER and then immediately press SELECT.


The DIAGNOSTICS main menu is displayed on the OSD and d01 is displayed on the front-panel LED. The DCT* is now in diagnostic mode.


This will show you power level and SNR = Signal to noise ratio (very important)

There will be other parameters, let me know what you read about these.

ok the SNR reads 34.2 dB GOOD/power level: 060 dB
 

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Quote:
ok the SNR reads 34.2 dB GOOD/power level: 060 dB

These numbers sound decent not stellar ( assuming power level is 0.6dbmv).

At this time the picture should be locked in, something is probably causing the signal to fluctuate causing the signal break up.

For these numbers an amp won't help you.


If possible the next time you notice the signal break up do the diagnostic test again.

For now if you know where the signal comes into the house and is distributed I would attempt to remove and examine the cables (center pin straight) and reinstall the connectors. (Tight).
 
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