Digibox - Setting it up
What you need...
- A Digibox
- A dish with a 'universal' LNB
- A 'sat-finder' or an old analogue receiver (if unable to see TV at same
time as aligning dish).
- A compass
Please note that the dish size depends a lot on where you are located. I am in northern France,
so within the beam catchment area of the Channel Islands. I have seen the "Minidish"
in use around here, but have, myself, chosen to use my 80cm dish because it is what I had.
The dish size also depends upon what you intend to receive. Perhaps, for the 'Sky' services,
you might require a 2 metre dish if you are living on the Canaries. To receive TV Canarias, on the
Canaries, you can probably make do with something more subtle than a 2 metre dish!
While this guide doesn't cover the BBC services, I will add that the BBC channels have been moved
to a beam that is fairly tight on the United Kingdom. While you should receive it in
Northern France, Belgium, and north-west Germany...
...if you have a sunny little fattoria in Tuscany, or an appartamento with private beach in
Palermo... then sorry, you're probably out of luck. It can't hurt to try though.
Aligning your dish
There are several ways you can go about this. The first is best, then a
correct way, then two rough'n'ready methods.
When I make reference to check the dish alignment using the Digibox, refer also the the
'switching on the Digibox' section below...
- DIGITAL - IF YOU CAN SEE THE TELEVISION...
This is the best way to tune, but it requires you to see the
television clearly while moving the dish - not always possible.
Set your Digibox's Default Transponder accordingly (
11.778 V 27.5 3/4
for 19.2°E).
Proceed as for #2 below, but instead of using a sat-finder, make sure
the Signal Test screen is up and use the Signal Quality. The Network ID
for the Astra 19.2°E satellites is 0001 (Sky's Astra is
0002).
Because you are using the Digibox's own 'quality' meter, it will give
you the most accurate report.
If you demand perfect results and wish to watch your satellite signals in
sub-optimal weather, then it should go without saying that this is the only
method of dish alignment that you should use...
- DIGITAL - IF YOU CANNOT SEE THE TELEVISION...
Wire up your equipment and put the dish pointing to 'sort of' the right direction. Wire in
your 'sat-finder'. My good friend Ewen Cathcart describes how to
get the best from a sat-finder.
Switch on your Digibox and go back up the ladder. Keeping an eye on the 'sat-finder', move
the dish very carefully until you get the best signal.
Now go down and try to tune into CNN (details on the channels
page) to ensure you've chosen the correct satellite!
Speaking from experience:
Some people don't like beepy-squeaky sat-finders.
They say that a strong signal isn't always a good signal.
I have had no difficulties in setting up a Digibox using
just such a sat-finder. In fact, careful use of even the
cheapest and most basic equipment will allow you to
home in on the satellite; this is something that is very
difficult to do with the Digibox's on-screen display due
to the small delays inherent in the system. So if you can
pick up a sat-finder for £12 (or less!), you'd be foolish
to turn it down. It makes re-alignment of the dish so
much easier!
- ANALOGUE - IF YOU CAN SEE THE TELEVISION...
The benefit to aligning with analogue is that when you point the dish
in the right direction, you can instantly see something. There is also
fade-in and fade-out with audio hissing noises. I can get a dish lying
on the floor pointed to Astra in under a minute.
The down side? A good looking analogue picture is not necessarily good
enough for digital, you have to take care and time to get the alignment
spot on (which can be hard as the analogue picture may look identical
for a degree of movement!).
Put your dish up, facing the right sort of direction. Put your analogue receiver outside
with a small TV, and hook the dish to the receiver.
Tune the receiver to 11627 V
and then move the dish until you see CNN.
Alter the dish carefully for the best picture quality.
Please use CNN for tuning as the signal strength is weaker than, say, CNBC or Viva.
Then, hook up your Digibox and tune into CNN (details here) to
ensure everything is okay. This will get you a signal, however the quality of the signal
can be extremely variable.
- ANALOGUE - IF YOU CANNOT SEE THE TELEVISION...
If the rain is piddling down and it is nearly midnight.....there
is still a way you can align any dish even if you can't see the
television and it is pitch black and you don't have a sat-finder!
The 'other other' way to tune... I use this a lot myself. It generally results in a lower
quality signal, however all of the pictures on the channels page were taken with the
Digibox hooked to a dish tuned using the acoustic method.
What you do is tap your dish and listen for a high-pitched pinging noise. The higher the
pitch, the more on-signal the dish is...
No, seriously... Proceed as per "the 'other' method" above, but now instead of
using a TV to see the picture as you tune in, you hook up a PMR transceiver to the audio
from CNN.
The way I do this is to force one radio into 'transmit' using a lego brick and a couple of
rubber bands. Place headphones around the radio, and shove a beer can between the back of
the radio and the other side of the headphones. This ensures the radio mic is up
close to the headphones speaker.
Pop on your favourite Alizée track to
check everything is working properly, then switch the audio to the analogue receiver.
Up at the dish... (actually, my dish is in the driveway, propped up using three ridge tiles
and a small rock!), aim the dish towards the satellite. Perform a slow and careful sweeping
motion to find it. Once you hear some hiss, stop. Wobble the dish to bring in sound. You
should hear an American girl talking about who just blew up who in Israel. This is important
as it is quite easy to point your dish at the wrong satellite, and end up looking at the
likes of Nile TV!
Here's the hard part. Move the dish left until you lose the signal. Note the position. Now
move the dish right and note where you lose the signal the other direction. Position the dish in the centre,
and then do exactly the same for up and down. With a little luck, you can lock the dish in place
bang on-signal. It's very hard though, as you only get a couple of degrees of 'play' with
analogue, and with digital you need a good signal (sparklies in an analogue picture
can be enough to kill a digital picture). So, for digital, your 'play' is less than a
degree. If your dish is in a place susceptible to wind, ensure it is locked down tightly.
My dish, as I've mentioned, is on the ground and propped up with ridge tiles. Luckily our
main winds are Westerlies so the house shelters the dish, but a strong cyclonic is enough
to knock it out of alignment. In fact, one storm last winter deposited the dish about
forty metres away in a field! :-) Actually, as of mid-2004 I reverted to a smaller (60cm) mesh dish. Not only does this give a better signal (I think the solid dish is suffering from its flying lessons!), it also has the great benefit that wind passes right through it.
You might ask why I don't fix it down securely. I'm tied to the length of the cable, and
the dish 'sight' of the satellite. The choices are to drill into a solid stone wall, and
I don't have the equipment for that. Alternatively I could try punching a hole through
the tarmac driveway which may have been overlaid on stone cobble (not by us, I
hasten to add). As you can see, the ridge tiles may be temporary, but they aren't a bad
compromise...
If you tune using the acoustic method and you can stand being out in the pouring rain
(some people like that kind of thing - look at that film with Gene Kelly and Debbie
Reynolds (though maybe not if it is -5°C!)) - then you are likely to get a more
on-signal satellite the heavier the rain is. Why?
Because on a beautiful clear sky there's nothing between your dish and the satellite except
a whole heap of air. With heavy rain clouds in the way, there's a lot of water vapour
there also. And satellite signals don't pass through water as easily as they do the air,
so it attenuates the signal; thus the hit'n'miss range is reduced.
Now, if you're going to get yourself wet, it goes without saying that you pick a warm day
to do this - unless you fancy a week feeling crappy and sipping the Lemsip. This would be
greatly enhanced if you have a partner/parent/child to assist you as you really
don't want to come inside and poke electronic equipment with water dripping off of you.
One drop inside your Digibox can render it quite dead. And as for getting water in the
back of a TV. Trust me, it isn't nice.
One final word - if you do the maths and figure that the ultimate signal block is likely
to be a cloud with serious mass, like a thundercloud or a hurricane, then you are quite
correct. However, do you think it is entirely sensible to be perched up a ladder
grasping a possibly-earthed metal dish while there's a storm raging or lightning rolling
from the sky? Really, it's a no brainer. Don't do it!!!
If you prefer to be warm and cuddly and dry, there is a way that you can see if you have
this rain margin. Any decent sat-finder will have a little switch on the back (or possibly
inside). The switch will be marked "0dB" and "-6dB". The exact meaning
of this is too much bother to explain, so just know that the "-6dB" setting is
your rain margin. You'd be best leaving your sat-finder at this setting.
Align the dish as described but leave the sat-finder in-line and go look at your
television. If it is all okay with the -6dB reduction in signal, you have a suitable rain
margin.
If you don't have a signal, switch the sat-finder to 0dB and check again. If you now have a
signal then the problem is weak reception (no rain margin). If you still don't have a
signal with the sat-finder at 0dB then you have a problem...
One note to consider on the subject of thunderstorms - if you live in the UK and you have a
Digibox on the freebie contract - ignore the 'small print' that says it must always be attached
to a telephone line. As soon as a thunderstorm comes along, the wise person would disconnect the
Digibox entirely (power, LNB, antenna, telephone). Not to mention doing the same for
anything else electrical that is 'delicate' (computer, fax, modem, VCR...).
Additionally, if you are planning on spending two weeks in Tenerife, then I'd be inclined to
unplug everything and cut the power (unless the fridge/freezer has to stay on).
Electrical equipment can react very unpredictably when lightning gets into it (I've seen a
television blow itself apart (the PSU exploded, shrapnel took the tube with it)) and unless
somebody is planning to give me a cast iron we-will-replace-everything-if-your-house-burns-down
guarantee, then I'd say stuff the small print and unplug.
Incidentally, it works out cheaper for them too. During the contract, the Digibox is under
guarantee. No zapped box, nothing to repair or replace.
In Europe, where storms bite (if you've never left England, you have no idea) and where
the electrics are 'interesting' (or downright scary, if you're in Spain) and much of it in rural
areas is strung high (and thus asking to be hit), nobody in their right mind would keep stuff
switched on in a thunderstorm.
Sorry to have repeated myself a few times. I've seen lightning damage. Luckily the only thing I,
personally, have lost is a light bulb. Touch wood. A lot. Trust me, it ain't pretty.
The importance of a good signal
With the analogue system, the worse the reception was, the more 'sparklies' you would see in the
picture. Sometimes it was enough to cause the Sky's Videocrypt system to fail, but generally it
took a thunder-head to knock out the signal.
Actually, as an aside, I observed on a completely clear sky, the signal vanished for a second.
Upon looking for a reason, I saw a jumbo jet flying very high up. What d'you suppose are the
statistical chances of that?
A digital signal is more fussy. The system used is pretty resilient, but when the data corruption
is more than can be recovered, you'll go from mild corruption where movement is affected...
...to more severe corruption where everything is affected...
...to...
Switching on the Digibox
Ensure the dish is hooked up, and the TV is hooked up with SCART leads. If this is a second-hand
box, DO NOT EVER connect anything via the RF2 socket. I'll explain why in a moment.
Plug in the power. A little red light at the front should come on.
Now wait. And wait. And wait. The Pace BSkyB 2500B takes over twenty seconds to get itself going;
plus another thirty-odd seconds to notice that it actually has a valid satellite signal. It's
pretty slow. So slow, in fact, that I can (from standby) press Services
,
6
, and then Select
(for CNN) and it'll tell me that no signal is being
received. Unless you have a fast Digibox, don't try to be a speed demon. It won't work!
Press the 'power' button on the front panel or the remote. The red light will turn green. On the
TV you'll see it say that it is searching for listings, followed by a complaint that no satellite
signal is being received.
Do not panic! It can be receiving a perfect signal, but if the symbol rate and the FEC
(Forward Error Correction, it's nerdy so don't bother with an explanation) are not correct, the
box will tell you there's no signal. Remember people, this device is intended for the Sky service
which is essentially plug'n'play, so no, the box won't bother scanning different symbol
rates (actually, it only supports two!) and FECs.
Press Services
on the remote, then press 4
, then 0
, then
1
, and finally press Select
.
Do not worry if nothing appears to happen as you press zero and one. It is a 'hidden' menu, so
simply press the keys given above and ignore the screen, the menu will turn up...
The screen will look like:
If your LNB is non-standard, you can choose option 1 to set up the low/high local frequencies.
This is unlikely, though, as most universal LNBs work the same way (9.75/10.6 with 22kHz switch
tone). No, the Digibox doesn't support DiSEqC. It is designed for Sky, remember, so changing
satellites isn't really an option with the Sky package!
If you want, you can go to option 2 and set the default transponder to
11.778 V 27.5 3/4
- which is nearly the same as the Sky
default (the Sky default is the same, except the FEC is 2/3).
This frequency, normally, (on Sky) carries the EPG data, however there isn't any such thing
available on Astra 19.2°E, it is CNN and some other channels...
Why bother changing the default transponder? The reason is simple - if you ever plan to check
the signal quality, it uses the signal from the default transponder. Incorrect settings equals
'no signal'. It's up to you.
If you plan to hook anything to the RF2 output, go into option 4 and ensure that the power is
turned off. The Digibox can output 9V to power a Digilink unit. Plugging 9V into the back of a
TV is unlikely to be friendly to it.
Question - what if your TV has no SCART socket and neither does your VCR? Apparently the power is
only applied to RF2, so use RF1... Best to double-check with a multimeter though... Once the
UHF power is off, you can safely use RF2.
Additionally, you can use this setting to alter the UHF output frequency if it clashes with
anything. I've set my Digibox to UHF21 (same as the analogue) as my teletext receiver expects to
'see' something at UHF21, I'm only going to be using on receiver at a time, so it's no problem
to move the UHF lead - I've got to move the power, LNB, and SCART anyway.
You can now proceed to tuning... Since we are here, we'll use the Manual Tuning option...
Tuning in a channel
If you have a good reception, you can add channels using the 'Add Channels' option
(Services
, 4
, 4
on your remote).
If your reception is less good, you might prefer the 'Manual Tuning' option
(Services
, 4
, 0
, 1
, Select
,
5
). The only difference is that the 'Manual Tuning' option pops up the signal
quality display while it is looking for channels. You can use this to judge if things are okay or
not, as might be the case with a roughly-installed dish, fringe areas, or bad weather.
Enter the details for the channel you wish to receive...
Here, we are going to tune into CNN. Press Select
to continue...
If you are performing the Manual Tuning, you will see the signal quality appear (otherwise you
will see just the backdrop for a few moments). As you can see, my signal strength could be
better. The signal quality is okay for the current weather (-7°C and totally clear) but rain
might cause picture break-up.
The Network ID and Transport Stream numbers will change, and the Signal Quality will vanish. So
count to five slowly and then press Select
. You'll see...
Simply highlight the channel(s) that you wish to receive by moving up and down and pressing the
Yellow
button for the channel. Press Select
when you've chosen them
all. You'll then see...
Pressing Select
will take you back to the frequency/pol./sym/FEC settings screen so
that you may add several groups of channels at one time.
Notes:
- Unlike channel reception that you may have been used to, the digital channels are offered
in a 'boutique'. Sometimes you can see only a couple of channels (6 to 8 is usual), but if
a frequency carries radio channels, you might see more than a screenful!
The way this works is your Digibox receives ALL of the channels at a given polarisation
from the LNB (just like analogue receivers). This is similar to the way your radio antenna
receives ALL the stations. The Digibox then tunes the desired frequency (again, like the
older receivers or a radio). The next step is that, using the symbol rate and the FEC, the
Digibox figures out what this data-stream is actually supposed to be. At any given time,
your Digibox will be receiving several channels. It may receive only one, or it may receive
over twenty. It simply sorts through all of this mass of data to pick out which bits belong
to the channel that you are currently watching. This, sorted, data is then passed to the
MPEG decoder for decoding and display.
- There is an important caveat - the Digibox only has 50 slots for 'other' channels. You will
need to examine what you actually want to receive. What are you likely to be interested in?
There are many channels available at 19.2°E - there are probably more than 50
German channels alone!
This, again, reflects the Digibox's commitment to the Sky package. After all, as soon as
you power up a box on Sky you get the EPG with full programme details of thousands of
channels you never knew you wanted to watch - so who is actually going to use the Other
Channels option on Sky?
Thankfully, 50 channels isn't too restrictive. Here is my current channel selection
(38 channels):
Now that your Digibox has been 'set up', it's time to go about using it!
By the way - the Lemsip reference above is definitely a recommendation. The stuff worked
wonders on me when I used to work in nursing homes (places where all the bugs came for the
holidays).
Sadly, I've not found anything like it in France so I tend to drop a fizzy paracetamol into hot
water, and squeeze in the juice of half a lemon. Not quite a Lemsip, but as close as I can get
right now...
Copyright © 2005 Richard Murray