maximum coax length??

adam2002

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I need to move my motorised dish. can anyone suggest the maximum coax distance before I begin to loose strength or my receiver stops driving the motor. It is currently 65 metres but will need about double that after the reloc.

:confused :confused
 

rolfw

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If you are going to have a coax run of 130 metres, then you will probably need a bigger dish than 80cm or a line amplifier (perhaps both), as the loss over that distance is quite high, even if using a larger core coax cable.

If you use WF165 or similar, you would get a loss of between 17db and 26db (depending on frequency) over the 130 metres, so you need a pretty healthy launch level. Not sure how the voltage will cope over that distance, have never tried to power a DiseqC motor on that length of cable and of course a line amplifier would draw yet more.
 

Steve_N

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I don't know which motor you have, but with a Stab for example the maximum length of 'standard' 1.02mm centre conductor cable (e.g. CT100,PF100,WF100 etc.) is 30 metres. From 30 to 60 metres larger cable is required (xx125 presumably) and the implication is that distances of over 60 metres are not praticable. I guess this is due to voltage drop and resistance in driving the motor rather than degraded signal strength.

You can see the Stab cable specs. in the PDFs on www.stab-italia.com
 

adam2002

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Thanks rolf for the advice and steve also.
just to let you know I reached a compromise and chainsawed a few trees to shorten the move. 88 metres, rg 6 and my criptik polar mount still works fine, although it may be a little slower....hard to tell really and no signal loss either. should do me for another year or so!
 

rolfw

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Ah, a man after my own heart. :):-saw
 

wod

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off topic but whats the best cable to use as i'm using ct 100 atm is that ok is there any better stuff to replace it with
 

rolfw

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CT100 should be fine if your run is under 30m or so, otherwise use a 1.25mm or 1.65mm core cable.
 
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