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Discussion Starter · #1 ·
I have purchased RadioShack "20DB COAXIAL UHF in line amplifier" with the range of 430-1450 Mhz. The result surprised me. Dish 6000 showed signal strength as 0 on all channels. Removing it brought it back to a range between 35-87 on different stations. What is the HDTV transmission frequency? Does this thing broken or just filters out HDTV?


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Vadim
 

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Most likely you're over-amplifying the signal. You should probably work with antenna placement before working with a 20dB signal amp. Those are typically used to help against attenuation for long cable-runs.
 

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I had the exact same experience with the same amp. Looks to me as if the input of the 6000 "over-saturates" and shuts down fairly easily. Mine's going back tomorrow.


Almost all of the local DTV stations (total of 11) had a signal stregnth of 75 or more. The one station that I really wanted to get had a typical signal stregnth of 50 to 60 and LOTS of dropouts. I thought that the Radio Shack amp would help. What it did was KILL everything.


Oh Well...
 

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Remember that the "signal strength" meter is not, in fact, measuring signal strength. It is telling you the "quality" of the signal at the demodulator; basically, how cleanly the bits are being received, and how easy a job it is having telling a 1 from a 0.


Due to the way receivers are designed, the demodulator making this measurement has no idea what the signal strength actually is.


Now for satellite signals, the meter is pretty indicative of signal strength, as that's basically the only thing that can mess up satellite reception in most installations. For OTA, though, weak signal is only one factor that can cause a poor quality signal, and it's not the most common one. Far more common is excessive multipath that the demodulator can't cancel out. In your case, it sounds like either the amplifier or the front end of the 6000 was being overdriven by excessive signal strength.


[One of these days some of us need to write a FAQ for this forum; some issues, like this, come up alot]


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You have a right to install OTA and dish antennas on property under your control.


See http://www.fcc.gov/csb/facts/otard.html


[This message has been edited by BarryO (edited 07-04-2001).]
 

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That particular Signal Amplifer is out of bandwidth for KU Band satellite. You need an amplifier of 50~2150 MHZ frequency range.


If your signal is weak. Best way to resolve it is to:

- shorten the cables.

- remove all spliters and couplers.

- make sure use RG6 cables, and connectors compatible with RG6 (Radio Shack's weather proof connectors).

- carefully pointing your dish, and make sure there is no obstacles.

On DISH 119, you should get over 100% singal strength on most the TPs. On DISH 110, you should get over 85% signal strength on most the TPS. On DISH 61.5, you should expect over 90% signal strength.

AND YES, SIGNAL STRENGTH MEANS SIGNAL STRENGTH!


My experience with signal amplifier is don't use them. I have tried all kinds of amplifiers and ended up returning them. The only one that worked to a minimal extent was a Radio Shack product (with the right frequency range), in that case the singal strength improved by 2 points. Where you put your amplifier on the cable is also important, you have to experiment a little bit: middle of the line, near the dish or near the reciever.
 

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Eugene,


I believe Vadim was talking about OTA reception of terrestrial broadcasts with the 6000 via the 8VSB module, and not reception thru the 61.5 degree satellite.


If I'm mistaken, your points are valid.


P.S. The satellite signal strength numbers you quote may be typical for those in the Southern U.S., but those living close to the Canadian border would have difficulty getting numbers that high!


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You have a right to install OTA and dish antennas on property under your control.


See http://www.fcc.gov/csb/facts/otard.html
 

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Discussion Starter · #7 ·
Thank you Barry for clarification. Indeed, I was talking about OTA. Have no problems with 110 and 119.

FAQ is a wonderful idea. I would be happy to add whatever's left of my free time to the project if someone will lead it. It should add a lot of value.


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Vadim
 
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