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Discussion Starter · #1 ·
I had to split my Dish 501 receiver two ways. I'm running 100' of new RG6 cable from downstairs to upstairs. My signal strength is around 100 for 119E. I just bought a 20" Sony flatscreen and the picture seems a little grainy. The picture didn't seem to change much from the samsung 19' TV that I just replaced. Are the In-Line amps only good if you are having low signals.....any suggestions on improving the picture upstairs? I messed with the sharpness etc...


Thanks,

MIke
 

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if your are running the output of your dish unit thru 100ft of coax to the tv upstairs you are going to have a problem. The fcc limits the maximum rf output signal strength of the dish box to about -5dbmv. 100 ft of really good cable is going to loose at least 3db so the signal at the set ends up -8dbmv and that is not enough for a good picture. A high quality 20db amp at the dishbox is what you want.
 

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Discussion Starter · #3 ·
Kevin,


I looked in the back of my dish receiver..I have the TV out going to a 2 way splitter then the 100' goes to the upstairs. Is this what you mean. Could you recommend any certain brands of 20Amp and where I could get them.

Thanks,

Mike
 

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yes that is exactly what i mean. The splitter takes another 3db out if the signal, so by the time it gets to the tv upstairs it is

down to -10dbmv.


Now in them olden days when tv tuners were really tv tuners

-10dbmv was plenty of signal. Zeniths spec at the time was -25dbmv for a good picture. That was then. Now tv tuners

stink.


As for distribution amplifiers i use a pair of 30db amps made by american microwave technology. (You will NOT like the price, trust me)


There are devices out there called the DA100 and DA400 that are pretty decent. I do not remember who makes them. They are in the mcm catalog.


There is this one too...

http://www.smarthome.com/7708h.html
 

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The amp you bought uses phantom power and is probably not the right thing. It is probably for hooking to the dish itself for long runs of cable to the satellite box. As such it is typically 800mhz to 1500 mhz, and will not work on channel 3 or 4. Here is a picture of a low band phantom amp with its phantom power supply. It is the circular thing in the back.

http://gilmore.chem.nwu.edu/wiring1.jpg
http://gilmore.chem.nwu.edu/wiring2.jpg


I use the inline amp for the fm stereo antenna only. It is in my opinion lousy for quality television. Radio shack sells these complete with phantom power supply. For inline use without a cable you will need a male to male f connector. In the second picture the blue thing with the heatsink is the amt amp i use. The thing to the right is the power supply 28 volts at 1.5 amps.


You can certainly build your own if you know how.

http://gilmore.chem.nwu.edu/amps12.jpg


The top picture is an acrian part model 201. Very nice. Pricey.

The bottom picture is the venerable motorola (now ON semi)

part used in every cable system in the world.


If you want to make sure your neighbors can also see your picture

you can use one of these. No cable to the neighbors required.

(will probably get the fancy candy company a little hot)

http://gilmore.chem.nwu.edu/amps34.jpg


The top one was build by yours truely 25 years ago while at zenith.


The bottom one is a standard minicircuits unit, puts out about one watt.


Just in case you really want to get arrested, only this will do :)

(Don't do this, really...)

http://gilmore.chem.nwu.edu/amt.jpg


No reason not to be excessive...
 
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