maximum coax length??

A

adam2002

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My Satellite Setup
Force D master 1122
sky digibox with freeview card.
80cm dish with motor
My Location
France
#1
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

rolfw

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Technomate 5402 HD M2 Ci, DM7000s, Transparent 80cm Dish, Moteck SG2100 DiseqC motor, lots of legacy gear. Meters: Satlook Digital NIT, Promax HD Ranger+ spectrum analyser.
My Location
Berkshire
#2
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.
 
S

Steve_N

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Analog: Amstrad SRD520, Lenson Heath 80cm.
Digital: Technomate 1500ci+, Stab HH90, Gibertini 1m
My Location
Dundee, Scotland
#3
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
 
A

adam2002

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My Satellite Setup
Force D master 1122
sky digibox with freeview card.
80cm dish with motor
My Location
France
#4
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

rolfw

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Staff member
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My Satellite Setup
Technomate 5402 HD M2 Ci, DM7000s, Transparent 80cm Dish, Moteck SG2100 DiseqC motor, lots of legacy gear. Meters: Satlook Digital NIT, Promax HD Ranger+ spectrum analyser.
My Location
Berkshire
#5
Ah, a man after my own heart. :):-saw
 
W

wod

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1m channel master, jaeger smr1224, Inverto black ultra twin, technomate tm-1500ci, broken receiver vantage x221ci, New additions Skybox F5s and technomate tm-5402 HD arriving soon.
My Location
yorkshire
#6
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

rolfw

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1,291
My Satellite Setup
Technomate 5402 HD M2 Ci, DM7000s, Transparent 80cm Dish, Moteck SG2100 DiseqC motor, lots of legacy gear. Meters: Satlook Digital NIT, Promax HD Ranger+ spectrum analyser.
My Location
Berkshire
#7
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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