"mike" wrote in
message ...
On 29/11/2010 07:52, George Reid wrote:
On 28/11/2010 20:30, mike wrote:
By a process of elimination I figured out it was one of the
two cables.
I swapped the cables around on the LNB and the fault switched
from one
tuner to the next. There was a joint in the cable and this
was letting
in water, easily repaired and as good as new in minutes.

...I've done that, or similar - swapped connectors at box end.
Still
poor or no signal on tuner 1. Can I take it that cable and
dish are,
therefore, OK?

Phoned Sky last night. As I was describing problem, the signal
came back
on those channels where it had been lost. Operator said she
couldn't
arrange an engineer since the fault was not happening. I
should call
back next time it happened! Thirty minutes later, signal on
tuner 1 was
lost again.

I would say so. If the signal was fine on tuner 2 and after
swapping the connectors around the box end tuner 2 was still
fine then you've eliminated the dish and the cable as a fault
that only leaves the tuner. If it where the cables/dish I would
expect all the channels to be lost as the signal comes from the
same satelite but someone more savvy might disagree!

With mine swapping the cables produced the opposite result in
that the fault moved from one tuner to the other.

If you really want to be certain do you know anyone with a Sky+
or HD box who can bring it round and plug it in for a few
moments? Leave their card in their box and just check the
signals.


Mike

Mike commented that "if it were the cables/dish, he would expect
all channels to be lost". That is not correct, for the following
reasons:

1. Transmissions on the Sky platform come from two clusters of
satellites. Astra 2A/2B/2D are located at 28.2 degrees East.
Eurobird 1 is located at 28.5 degrees East. If the dish
alignment has moved very slightly, it could lose signal from one
or other of these satellites.

2. The Universal LNB incorporates switching mechanisms, which
receive vertically and horizontally polarised transmissions &
high and low band frequencies. A switching mechanism in the LNB
might have developed a fault.

3. The Sky receiver sends switching signals to the LNB. If
the Sky receiver does not send the correct switching signals to
the LNB - it will cause the loss of some, but not all channels.

I wonder whether the OP's Sky receiver was manufactured by
Thomson. If so, the Power Supply Unit in Thomson Sky+ and Sky HD
receivers is prone to premature failure. A defective PSU can
produce the symptoms that the OP has described. (For further
information, see www.satcure.com/tech/thom_psu.htm).

We still don't know whether the OP has a faulty receiver - or a
problem with his dish, LNB and/or co-ax cables. Connection of a
different Sky+ or Sky HD receiver to the OP's dish should help to
identify the cause of the problem - and should confirm whether
there is a problem with the dish, LNB and/or co-ax cables.

Or, the OP could take his receiver to a friend's house and
connect it to his friend's dish. If the problems continue at a
different location, he will know his receiver has developed a
fault.

"George Reid" wrote in message
...
Over past week or so, I've had recordings fail and, last night, while

Or even losing signal.

OK, I noted the spelling error, but it was too late to rectify.

Box is Amstrad.

Odd thing is, now input 1 is better than input 2. Swapping cables does
not change this. Still feel that it is a box error. Engineer coming
today (weather permitting), so might have more idea of what is
happening. Will report his findings.

Watching the signal strength 'meters', I note that the strength on both
inputs fluctuates wildly from zero (on both) to 80+ (on both) with
frequent high-low pairings (input 1 being high).

I get the impression that input strengths are OK immediately after
taking box out of stand-by, but after about 30 minutes losses become
apparent. Will have a look at that now, and see if I can duplicate this
for engineer.

--
George from Cartland

Well. Snow has delayed engineer's visit. Will continue thread when this
has been re-arranged.

On 03/12/2010 15:32, George wrote:
Well. Snow has delayed engineer's visit. Will continue thread when this
has been re-arranged.

Sky engineer - well, two of them - arrived yesterday. After I'd
described symptoms to Engineer 1, he decided that it was "probably the
tuners" and swapped out the box for a new one. Meanwhile, Engineer 2
replaced the LNB "just in case". All FOC.

So far, 24 hours later, I have had no loss of signal.

Result. Credit where credit is due. Can't fault this service on any
count. They went beyond what I was expecting them to do. I am a
satisfied Sky customer (for the time being!)

--
George from Cartland