1. Replacing your minidish LNB 2. Replacing the cable 3. Missing channels 4. Tuning the RF channel 5. I have only one LNB feed. SKY+ and Replacing your minidish LNB" Quad-output" or "OCTO" LNB This can feed up to four separate receivers (eight with an OCTO). Each receiver has independent control of polarisation and band via 13/17 volt switching and 22kHz on/off respectively. This LNB is also used with the new Sky Digiboxes that have two LNB inputs and internal Hard Drives for recording a programme while you watch another. Two LNB outputs go to this "Sky Plus" Digibox and the other two LNB outputs can go either to two standard Digiboxes or to one other "Sky Plus" Digibox. You'll also need to add a cable run from the LNB to your Digibox. You can run a single cable or you can replace the existing cable with twin cable ("shotgun"). Shotgun cable comes in two sizes. A very thin type (CT63), which is OK for up to 20 metres and fits through the existing 10mm hole in the wall, or a high quality WF100 type which is recommended. Sky "Minidish" upgrades Here is the Philips SC519QS/S Quad output LNB which used to be supplied with the SKY-plus system. The red arrow points to the special oval shaped "scalar" steps in the feedhorn. These cause the LNB to focus exactly on the oval shape of the "minidish", using the full dish area but without picking up reflections from the wall behind. Loosen the clamp screws and turn the LNB so that the sharpest point of the oval "cam" (red arrow) is at the top. (Other LNBs may have a slightly different "skew" adjustment). Some dealers, who are either unscrupulous or simply know no better, are offering a standard Twin-output or Quad output LNB with an adaptor to fit the "minidish". The adaptor fits a treat. Unfortunately, the LNB will not give optimum performance because it's designed for a circular dish - resulting in "rain drop-out" during bad weather. All the LNBs on our "Sky LNB" page are designed for use with an oval minidish. However, you may prefer to buy a standard circular (as seen by the LNB) dish of, say, 60cm diameter and use a standard 40mm neck twin-output or quad-output LNB with this. The match and fitting will be perfect and the "rain drop-out" will be very rare in England. For more information about the various types of LNB, click HERE. Replacing the LNB First, look in the on-screen menu and make a note of your current signal level and signal quality and write them down as a percentage. Ensure that your minidish is firmly fixed in place and no bolts are loose. Some LNBs are secured to the arm with a little plastic pin under the dish arm. Pull this out with a pair of cutters or similar. Some LNBs have a little locking tab visible in a hole under the dish arm; pressing this tab or button into the arm can make removal easier. Hold a piece of thick card or thin wood against the LNB face (the part nearest the dish) and tap it away from the dish with a mallet or block of wood. Its spigot should pop easily out of the hollow metal arm. If a rubber "boot" is fitted, slide it down the cable. Otherwise, with a sharp blade, cut away the black self-amalgamating tape from the cable connector and unscrew the connector. You may need a suitable spanner (10mm or 11mm). Fit the new LNB to the hollow dish arm using the adapter provided if necessary. Reconnect the cable, fitted with weatherproof rubber boots, or seal it with self-amalgamating tape. As the additional weight of the LNB and cables can make the arm sag, you may find that the dish needs adjustment now, and again after a week or two when the arm has sagged more. The best recommendation is to fix a piece of piano wire, fishing line, or strong non-stretchy nylon cord to a hole in the top lip of the dish. Pass the other end of the wire/cord around the LNB and adjust it so that it supports the additional weight. Read the rest of this page, below, for more information. Replacing the cable You can add another single cable or use twin cable. You can buy two types of twin ("shotgun") cable: WF65 which is thin enough to pass through the original 10mm hole in the wall. However, it has about double the signal attenuation compared with "normal" cable so it can only be used for about 20 metres maximum unless you fit a larger dish to compensate for the inevitable signal loss. WF100 which is a 7mm diameter high quality "CT100" equivalent with a foam plastic dielectric that resists kinking and prevents rainwater from running fown the cable, as can happen with an air-spaced dielectric. Click HERE for more info about cables. Here is a Cambridge AE140 quad-output LNB with weatherproof rubber boots fitted to the cables. These can be easier to fit than self-amalgamation tape (but we stock both). More info about boots. Info about fitting "F" connectors. You can buy twin "shotgun" cable. This can be either WF65 (thin) stuff that can be pushed through an existing 10mm diameter hole, or twin WF100 which will require a larger hole (or split it and feed each cable through a separate hole). See these twin cables. More info about cable.
Channels missing after fitting a Quad-output (or OCTO) LNB? >I have a BSKYB 3000 Sky+ digibox with a minidish and quad LNB. There is >an intermittent 'No Satellite Signal Received' error message which occurs 1 - >2 times per week for about 12 - 24 hours each time. When I swap over the >LNB inputs the fault transfers to the other channel (indicated by the >Signal test meters built into the digibox). This would seem to inidicate a >fault on either the cable or the LNB wouldn't it? I have already had the >LNB replaced once, which seemed to cure the problem for a few weeks, then >it started up again. > >Something which I find odd - if I switch off the LNB Power Supply in the >Installer Menu, I still get a signal on both channels - is this normal? My >second digibox loses its signal if I switch off the LNB Power Supply. > >I also have a second Pace digibox connected to the Quad LNB which since >the engineer replaced my LNB now has an intermittent fault on ITV only. >Again the 'No Satellite Signal Received' message, but if I wait for up to >5 minutes, the channel is received as normal. If I change to another >channel, it is received straight away, but if I change back to ITV, the >problem then repeats. > >Any suggestions would be gratefully received. > >Many Thanks >Steve The LNB accepts its power on any of the four inputs. If you switch it off on one, it should make no difference if it's still receiving power from another. Athough an intermittent cable fault is possible, it's not likely and it's easy to check by swapping the connection at both ends. As you've had the LNB replaced, I would discount that as a possibility. Replacing the standard LNB with a heavier one tends to bend the dish arm slightly. An "engineer" will compensate for this by adjustment. It sounds as if you may have employed a "ladder monkey" instead. Having the LNB sitting too low puts it slightly off the focal point, resulting in loss of signal from one or more satellites in the Astra cluster. Experience suggests that the one most likely to be lost is Astra 2D which has a "tighter beam" and carries ITV, Disney etc. You can check this by looking up the tuning parameters for ITV and typing them in to the "Manual Tuning" menu which you'll find in the secret Installer Menu, as follows.
Press [services] [4] [6] for Signal Test
Look at the signal strength for the default transponder. signal and quality will normally be at least 40%. Higher is better. OK, press [backup] several times to return to the programme screen.
Now press [services] [4] [0] [1] [select] [5] Enter parameters: 10.832, H, 22.0, 5/6 Move highlight bar to Find Channels and press [select]
Look at the signal strength. If it's low then get your dish aligned properly. This may be as simple as raising it a fraction of a degree. (Signal Quality drops to zero in this menu screen for some Digiboxes. However, if it gives a reading with yours, adjust the dish for maximum "Quality").
Press [backup] on your remote control then press [5] and make sure that the default transponder parameters are back (see below). If not then correct them and highlight Find Channels then press [select] 11.778, V, 27.5, 2/3 OK, press [backup] several times to return to the programme screen.

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PROBLEM Recently had sky plus installed. Previous sky box moved to sons bedroom. Prior to the addition received Sky and video throughout the house. Since installation the TV tune in for sky appears to have moved and no reception as previous throughout the house? My observations: Reception on main TV only throrugh AV1 (scart) reception throughout house extremely poor quality Antony It seems that the Sky ladder monkey didn't bother to set the output channel of your Digiboxes. Here's the quick fix. If the standard Sky Digibox was working OK, do this. Connect it via Scart to a TV. Press [service] 401 [select] (press these quickly). Press 4 (RF Outlets) Write down the RF Channel Number (default is 68). Now connect your SKY+ Digibox via Scart and do the same. Set it to the channel number that you wrote down and save the settings. Press [backup] several times to get out of the menu system. Everything should now work as before. Now go back to your standard Sky Digibox and set the RF Channel Number to something different. This must be an RF channel that is not already being used by any aerial transmissions or by any signal that you are sending from downsairs (eg. VCR, Freeview, DVD). Switch all the equipment ON to make sure there's no interference. If there is, choose a different RF channel number. Finally, tune the TV set(s) in to the Sky Digibox(es) as desired. Tuning TVs is explained in much more detail in our eBook "Piping TV Around the House". I have only one LNB feed It's impossible to get another. How can I use my SKY-Plus Digibox? See this page.

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