Hi

Quick “front end” check list:

The old Oncore modules were not the greatest for sensitivity. Compared to what 
you get today, they are a bit deaf. What that 
turns out to mean is that you need a bit more antenna gain with them than with 
a newer module (either a newer Oncore or a newer
part from somebody else). Something around 30 db of antenna pre-amp gain with < 
10 db of coax loss is about right for them. They 
will overload if you get up to the 39+ db preamp range and < 3 db of coax loss. 
How much they overload depends on the crud in 
your local environment. 

The Lucent boxes (like just about all similar gizmos) put out +5V to the 
antenna . There are indeed antennas that need > 7V to do their
thing. How well they work / if they work at 5V - who knows. I would not try it. 

Since you get a “40 - 50” db signal to noise once you lock on to a sat, the 
preamp gain is a bit weird. It very much impacts satellite 
acquisition, and has less impact once you are locked on. A marginal antenna 
gain can give you a “long start”, but then lock on to 
a number of sats once things get going. That can make it tricky to spot the 
problem.

Bob

> On May 30, 2015, at 9:38 AM, Martin VE3OAT <[email protected]> wrote:
> 
> Ulli,
> Sorry that I haven't been following your correspondence so I am coming into 
> the middle of this.  The fact that you receive so few satellites says to me 
> that there is a problem at the front end.  You said you had changed the cable 
> to the antenna and the antenna itself so those parts seem OK at least.  Are 
> you using an active antenna and does the unit provide the required voltage 
> for it?  Sorry if you have already checked that.
> ... Martin    VE3OAT
> 
> Ulli wrote :
> > At least, i saw 1 or 2 satellites from time to time.
> 
> 
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