Quote:
Originally Posted by SanDiego_air
I"m using a amplified splitter which provided 4 dB gain into each output. I thought that by using an amplified splitter, I was improving the signal?
Do i need to get a pre-amp for UHF?
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Sorry, I missed that the splitter that you had was amplified. The splitter is a very good one, but designed for CATV systems where all the signals are the same level.
Here's it's spec sheet;
http://www.channelvision.com/index.p...product_id=254
The output level rating is +23 dbmv assuming 160 channels all with the same level and analog TV. With the 5.5 db typical gain the input rating would be +17.5 dbmv (+17.5 dbmv is equal to -31.25 dbm) Adjusting the spec to two channels yields an input capacity of roughly -7.25 dbm. At that level, the intermodulation products are 60 db below a single carrier. The VHF stations on your TVfool report are -23.3 and -24.1 dbm, but that's average power. The gross peak power on those two stations is about -11.5 dbm (ignoring antenna gain and line losses). The amplifier is very close to saturation.
In an off-air environment amplifiers must be selected very carefully. The distribution amplifier that you have is not optimum for your application. The suggestion of a AP4700 preamp removes the possibility of VHF overload. The distribution amplifier should be removed from the system.