• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

TV/SAT Indoor Amplifier

al_madhi

Regular Member
Messages
118
Likes
1
My Location
Riyadh - Saudi Arabia
#1
Hi ppl wondering if anybody can tell me what is the correct way to connect a Tv/Sat Amplifier - Frequency range for Tv 47 -860 Mhz & for Sat 950- 2150 MHz
to amplifies weak signals . As it says indoor amp. that's means to be connected indoor near the receiver , By doing so when weak signals pass through down cable 35 m ( 99 ft ) long coming from DiSEqS switch at the top , the weak signals become very weak due to the resistance of the cable , then the amp. will amplifes very weak signals instead of weak signals .
I am thinking if I connect the amp. at top near the DiSEqC switch , in this case the amp. will amplifies weak signals but not very weak signals ., Therefore weak signals will be boosted so that they can overcome the resistance of the long down cable .
Any thoughts you would have be greatly appreciated .
 

rolfw

Believe it when I see it Admin.
Staff member
Messages
37,652
Likes
1,272
My Satellite Setup
See signature
My Location
Berkshire
#2
The ideal position for a line amp on a satellite feed is halfway along the cable apparently, although I have fitted them shortly after the LNB with reasonable results (only on small dishes though).

Is the unit you are speaking of a multipoint amplifier like the Johannsen?
 
Messages
1,514
Likes
1
My Satellite Setup
Pace 2200 Sky digibox with ftv card, Comag SL65 FTA sat receiver, 40cm Sky minidish, Setpal terrestrial receiver (for free uk tv only!).
My Location
Midlands
#3
unfortunately, adding the amplifier will always add noise, which only makes things worse (signal strength goes up, but so does bit error rate!). Only remedy, I'm afraid, is bigger dish or lower noise lnb.
 

rolfw

Believe it when I see it Admin.
Staff member
Messages
37,652
Likes
1,272
My Satellite Setup
See signature
My Location
Berkshire
#4
No, not the only solution spiney, there are situations (not many i admit) where a bigger dish is not possible and a line amp will improve reception where a long cable run is needed.
 
Messages
1,514
Likes
1
My Satellite Setup
Pace 2200 Sky digibox with ftv card, Comag SL65 FTA sat receiver, 40cm Sky minidish, Setpal terrestrial receiver (for free uk tv only!).
My Location
Midlands
#5
thanks, sorry, maybe i put that rather badly!

If the signal power goes below receiver threshold, then granted it won't get demodulated. But that's with an extremely long cable! Most receivers claim a lower threshold of 25uvdB, but in my experience many will work fine down to about 12 or 10 dB, at which point semiconductor noise starts wrecking the error correction.
Ok, if your signal level goes "below receivability", then a line amp will boost it, but at cost of adding noise, just watch the error rate shoot up! But you get something rather than nothing, i accept that.
A lower noise lnb is a better solution than a line amp, in my opinion, if possible, some aren't that much more expensive.
 
Messages
1,514
Likes
1
My Satellite Setup
Pace 2200 Sky digibox with ftv card, Comag SL65 FTA sat receiver, 40cm Sky minidish, Setpal terrestrial receiver (for free uk tv only!).
My Location
Midlands
#6
oops, I'm a complete dunce (but you aleady knew that).

Of course, SNR is critical on digital sat, but for analogue a much higher signal is required at receiver, maybe 50dBuv, and a line amp would be essential. Sorry.