A wander around the SL65

Me, on a Bad Hair Day, holding the SL65.
Me, on a Bad Hair Day, holding the SL65.

Goodness, you'd have thought I'd have brushed my hair first... Oh, wait, I did. ☺


I received this receiver third-hand, with no instructions, so everything here has been 'figured out'. Somebody sent me the instruction booklet PDF last week (March 23rd) which I downloaded. Since it was a large attachment and my mailbox was maxed out, I decided to delete it (and a few other large messages) and then send a thank you note.
Anybody with half a brain (i.e. not me!) will be wondering exactly how I planned to send a thank you once I'd deleted the email, where would I get the reply to address from?
Erm... Erm... Erm...
Whoever you are, THANK YOU! I have printed the user guide in case I need to refer to it, but I didn't do a bad job of figuring out this little receiver...


Switching on

When you switch the receiver on, the front panel display says "On", then "Strt". After a boot time of about four seconds, we flick to the first channel. The receiver appears to do this rebooting (only a shorter version) when you come out of standby, it appears to power down the reception and video circuitry (in order to save power).
Due to the design and operation of the Digibox (i.e. keeping the EPG up to date), the Digibox really only turns off the picture when you switch it to standby - that's why it always runs hot.
Not that running hot is an issue with the SL65!


Startup channel

If you don't like the idea of starting on channel 1, you can choose any channel to start on:
Choosing which channel to start with.
Choosing which channel to start with.
In addition, it appears that if you switch the receiver into standby (not off), it will remember the channel that you were watching, and if you switch it off, then on again the following day (for example), it will restart with the last channel that you were watching. Therefore it would not be unusual to see my receiver start up on channel 0014 which is Anime Central.
I think it is a useful feature. You might be less pleased if you switch on and find your kids were watching Babestation or the Playboy One previews... ☺

It is also a useful feature for people such as my mother who might not really want the complexities of learning to use a satellite receiver. By pressing two power buttons (the receiver and some sort of amplifier), she would be able to switch on to BBC Radio 4 - simply by setting it as the default start-up channel.


What's on? mosaic

A really interesting idea is the ability to see a mosaic of what is on. Just press the M/P key and the receiver will tune to each channel in turn and grab a miniature of each screen. The channel highlighted then plays in real-time, with sound. If you are interested, simply press OK to watch it normally.
A mosaic of what's on now.
A mosaic of what's on now.

It is worth pointing out that certain channels output video data in a format that the receiver doesn't appear to like in "miniature mode". Zone Horror was showing an advert, while ZoneRomantica, far from being scrambled (!), was showing the TV series "Beauty and the Beast" (with a young Linda Hamilton).

Another "what's on now" mosaic.
A mosaic of what's on now.


Going the other way

The thing about digital imagery is if your system is suitably powerful, you can mess with it a lot. Squash it here, stretch it there. Here is an example. First we will see the BBC lunchtime news on BBC News 24. Yes, it is signed (and subtitled) for deaf people, and at noon and not the middle of the night...
BBC lunchtime news, in full.
BBC lunchtime news, in full.
The receiver's clock, by the way, was set to +1 (European time) - that explains the disparity in the times. It confused me too, so I let it work on British time now; same with the VCR.

So now let's zoom in on the girl reading the news. This next picture is 6× (the receiver can do 2× to 16× in varying steps).
Look how clear the BBC's image is at 6×! Given this degree of quality, it could be possible to assemble, from a static picture, an image with dimensions 3240×1932. There'd be no point though, as that's about twice HDTV so there's nothing that's able to display it.
But it would still look pretty good, if only in our imaginations...

BBC lunchtime news, zoomed.
BBC lunchtime news, zoomed.

Actually... I watched the météo (weather) on a big LCD television in a supermarket. The picture was actually pretty awful. The problem is the MPEG signal can be expanded to 6× with no problem, and the television is about a metre wide. In between, however, we have the sticky problem of needing to squish the picture into a resolution of 576×720. This is cool for a 14" cathode ray telly, but it really doesn't scale up well to a big telly. Judging by the visual degredation, they also made the quality suffer thanks to a cheap splitter box (run two televisions from one signal) and it was probably either a UHF co-ax hook-up, or a very poorly assembled composite video hook-up. In any case it showed that the video in the receiver may be the epitome of digitally sexy and the television may be absolutely rocking... it's just that little problem of the cable between the two.

Anyway, click here for a more extreme example of scaling up the picture!



There is a Pause button. It does exactly what it says. Pressing it again resumes the picture from the current position.
I'm not sure how useful this would turn out to be, except to say that perhaps the receiver would have, if the hardware was present, the ability to start dumping video data to harddisc so you could pause a live programme and come back to it without missing anything... only as the SL65 has no harddisc, the pause just freezes the picture.
I assume the ALI chip used in the later SL65 is a work-alike of the popular STi5518 (used in the earlier SL65). The PremiumX 7000PGU FTA receiver can incorporate a harddisc, which would make the pause function more useful. For now, go figure why there's a pause button!


The on-screen info

The channel/programme information banner tells you quite a lot. Here's a run-down:
The channel info banner, explained.
The channel info banner, explained.

Pressing the info button pops up a display giving technical information on the channel including a signal stregth meter of the channel you are actually watching (the Digibox reports the signal quality for 11778V regardless of what you are watching). You've already seen an example of this, along with a slightly corrupt picture.

Pressing the epg button pops up a display giving a 'now and next' with a channel list. You can expand the information for the current programme. You've already seen an example of this, with the radio channel.

You can also call up the channels list, sorted by satellite or your favourites. As you choose a channel, you will see it in the space on the right, along with some basic techie information.

Channel list, with details.
Channel list, with details.
There is a simpler channel list, and - of course - you can just tap in the channel number.


Radio channels

When you choose a radio channel, it displays a fixed picture as a sort of backdrop, along with the info banner. This behaviour is similar to the Digibox, except you see a picture and not blank blue; and the EPG long description isn't shown all the time (it is on the Digibox). On the plus side, I really like this backdrop picture. It is stylish without being too much.
Listening to a radio channel.
Listening to a radio channel.



The receiver supports the standard Level 1.5 teletext - this is the rolling teletext service you may have used in the '80s and '90s on your television or computer (more info and RISC OS / DOS / Windows software here). Because the Sky Digibox supports interactive and videotext, there is little requirement for teletext services on the SkyDigital platform. Indeed some have gone - the expansive CNNtext is no longer. BBC's own text service (still broadcast on terrestrial) is little more than a page telling you to press the red button...
Internationally, the interactive services vary. The situation isn't helped by numerous incompatibilities - a Canal+ box won't work with TPS services, and vice versa. Receivers with interactive will work with some, not others. Nothing non-Sky will work with Sky (they split in a different direction to add TCP/IP support), and the Digibox simply doesn't provide red button support on 'added' channels.
Through this giant mess comes teletext. A British invention from the '70s, teletext has more than outlived its life-span, basically because it is easy to implement and it works. A BBC microcomputer built in 1982 can pick up and receive teletext broadcasts from any European satellite channel broadcasting teletext. It may mess up the character set and not understand accented characters, but this is due to its vintage. Slightly newer hardware, like an Archimedes (or faked under Windows using my WinTTX) will do the exact same thing and get the character sets right!

The ST20 processor used in the Digibox has support for teletext, so it seems odd to me that the receiver itself cannot display pages of teletext. It is as if Sky was trying to kill it off, rather than simply waiting for interactive to overtake it.
As for the SL65, not only does it handle teletext, with fast-links, but it seems to cache pages as they are received. As up to 800 pages can be stored, I know that I rarely have to wait, once the initial page has loaded. Perhaps if you press 'text' and go make a cup of tea, it'll have grabbed everything it could by the time you return. I'm not sure if it works like this, I have not tried... The user guide proudly says "Comparing our receiver to others you will notice that our Teletext is extremely fast". Indeed it is.

By an interesting quirk of design, you can read teletext pages that are broadcast on scrambled channels. Here is a page from the Irish channel RTÉ1:

A teletext page.
A teletext page.

I found out by accident something which is not described in the user guide. When you press 'text', the teletext appears in a 'solid' black rectangle over the top of the screen.
What if you would prefer it as a merged overlay?
Easy! The SL65 offers four levels of background - solid black, heavily opaque, just opaque, and transparent. You can cycle through by pressing the audio key. You can see a solid page (on a scrambled channel) and you can see the 'just opaque' overlaid on CNN, below.

A teletext page. A teletext page.



Being designed for the international market, the SL65 offers a variety of languages for the on-screen display, as well as selecting non-English as standard for the sound.
Here's an example of what I mean... it's all Greek to me!
The menus in Greek.
The menus in Greek.

In addition to this, you can select the television output aspect from:

and the television broadcast system from:
Setting up the TV system.
Setting up the TV system.
I find it interesting that the PAL is specified as PAL-B/G. This, technically, is the European standard which differs from the British PAL-I only in the "audio subcarrier" being at a different offset (hence a British TV in Germany/Spain won't receive any sound off-air). This, actually, is of little relevance to the SL65 which has no UHF output. Therefore I'd have expected to see simply "PAL"?


Timer events

The user guide mentions setting timer events from the EPG. This is fairly useless as the only EPG available is "now and next".

Up to eight events can be defined, by date and time. You can instruct your receiver to switch on to a specific channel, or you can ask your receiver to display a message.

If you ask for a message to be displayed, you are offered a choice of birthday, anniversay, or general message. For the first two, it may be useful to know that the receiver can repeat the alarm yearly...

Here is the birthday greeting:

A birthday greeting.

The anniversary and general ("wakeup") messages look like this (message only):
An anniversary message.   A general wakeup message.



When the signal is good, reception is good. That figures.

The main problem comes when the signal is weaker, fringe reception and/or unfavourable weather. In these situations, reception is actually considerably worse than the Digibox (Pace 2500B).
The SL65 is very quick at regaining from a lost signal, however it is also very quick at pointing out the signal has been lost - which has the potential of a rather stroboscopic effect as the signal comes and goes, and so the picture is replaced with a blank black screen with a thing like a shiny white marble and the message "No signal!". It would be better if the receiver would just freeze the picture for a few seconds, to see if the picture can be recovered without the need to blank it.
Additionally, in these situations, it would seem that the receiver is less choosy about how it 'builds' the display. Sometimes it appears as if the receiver outputs random junk to the screen, so while the Digibox can mess up with a bad input, the SL65 can mess up spectacularly with input that wouldn't actually cause that much disturbance on the Digibox (it would hiccup instead - so it is quite likely that the Digibox may entirely reject duff data instead of trying to display it?).
Something the SL65 doesn't do, however, is fall into the problem that affects the Digibox whereby during glitches there is a good chance of the audio losing sync or being lost altogether. I once taped a film where a gust of wind caused a glitch. I didn't think anything of it (I was outside at the time), but upon replaying the film that glitch lost the sound for the entire rest of the film. Lovely, huh?

Where the SL65 comes into its own, however, is when the signal deteriorates even further. Those times when the Digibox gives up completely and says "No satellite signal is being received" for everything. In these situations, the SL65 performs much better than the Digibox. Sure, two-thirds of the channels may have vanished into no signal territory, however those that remain (BBC1, ITV2, ITV4, Film4, etc) are often viewable with minor to moderate corruption. Certainly there is still a signal to be found - though you try telling that to my Digibox!

In short:

Wind and rain and gales, great viewing conditions!
Wind and rain and gales, great viewing conditions!



Explanation of DiSEqC.The acronym stands for Digital Satellite Equipment Control. No generic satellite receiver is worthy if it does not offer some version of this.
The purpose of DiSEqC is to offer a coding system for switching between a choice of LNBs hooked to one dish. A common use for this was watching Sky (analogue) on Astra 19.2°E and Hotbird at 13°E using one receiver, and one cable into the receiver.
Also possible is British digital television at 28.2°E and German/French/Spanish digital televsion at 19.2°E. With a good LNB or a big dish, you might also get Italian and east European digital television from Hotbird at 13°E.
As you can imagine, running three LNBs and three cables into the house is possible but it isn't very practical. So with a switching unit tucked behind the dish, your receiver would select which LNB to power up and receive from using control signals to the DiSEqC standard. Not only do you only need one cable going to the dish (as per always), but you can change channels across satellites simply by entering the channel number; the receiver will know what satellite each channel is on, and it will instruct the switching unit accordingly.

The SL65 supports:

DiSEqC v2.0-2.3 are not supported as they use a multidirectional bus so the switch/motor/etc can send information back to the receiver. Earlier versions are unidirectional only (the receiver only sends commands). This isn't a great hardship - it seems most non-HDTV receivers don't support the newer protocol either.


Support for multiple satellites

Something the Digibox would never do is DiSEqC. For this reason, viewing programmes on other satellites is not a pleasant task. To add to this, firmware modifications in 2005 rendered the box practically useless for international reception. It must now load the EPG channel data (from 28.2°E) before you can access the "Other Channels" list... which the stupid receiver tends to forget disturbingly frequently anyway. In short, the Digibox is pretty crap and nothing but a load of headaches if you think you're going to watch the Italians putting the hot into Hotbird. Options do exist, like a non-DiSEqC switch that operates from a hardwired 12V supply, so you can start the Digibox at 28°E and then switch to something else. However the price of getting this all set up Digiboxable could be comparable to buying and installing an FTA receiver with a regular switching arrangement. Forget the Digibox for multiple satellites and look at what an FTA box, such as the SL65, is capable of:

A monobloc, for Astra 19.2°E / Hotbird 13°E reception. By complete and utter contrast, any FTA receiver worth considering will offer DiSEqC. As explained just above, this comes in two forms. The early (1.0 and 1.1) are for controlling switches. Thus you can have a dish with two or more LNBs attached at fixed points. A switching device tucked under the dish will accept commands from the receiver and select the desired LNB. Selecting what channel to watch is as simple as selecting what channel to watch. The receiver will send the commands to change LNB, also adjust itself automatically if your LNB is a weird non-universal type (which may be the case if you are viewing C-band). Whatever, there's no headache at all.
Alternatively, DiSEqC can be used with a twin 'monobloc' (pictured left) to select which LNB to use. This is like two separate LNBs and a 2 way switch rolled into one device. No good for British TV, but it is frequently available here in France for watching both Astra and Hotbird (19.2°E and 13°E). The monobloc is a popular arrangement because it is often near impossible to have the two LNBs correctly positioned side-by-side. The picture of the monobloc shows how close the feed horns are to each other...

Multiple LNBs on one dish.. The fixed-dish-multi-LNB system works by using the fact that the dish acts as a mirror from many angles. Therefore you can point the dish at the main satellite you wish to watch (primary focus point) and strap on additional LNBs at the secondary focus points. These, obviously, will result in weaker reception as you are relying upon a side effect of the dish, and not all of the dish area will be used to receive. Not that this is necessarily a problem - if you look in the satellite press you'll see adverts for a Astra1/Hotbird "monobloc" (pictured just above), ranging up to the big dishes with six or seven LNBs off a second reflector (pictured left). It is possible. In fact, with a little bit of maths or a lot of fiddling around, it isn't only possible, it isn't that difficult.
The picture on the left, well now we are really showing off. To make a more compact and stable arrangement the main dish bounces the signals off of a smaller inverted dish, with the LNBs back to front in between. Just look at that dish. Doesn't it look a lot more stable and secure than a dish with multiple arms or, worse, one arm with multiple LNBs hanging off? Notice also the second dish is convex. This will help to separate the signals from each bird so the LNBs don't need to be crowded practically on top of each other, and should also help reduce interference between adjacent satellites.

A large single LNB dish on a rotator.
The dish rotator mechanism.
The logical alternative to the multi-LNB setup is to have one LNB, always at the primary focal point, and move the dish itself. Again we can see a reflected signal, placing the LNB away from the end of the pole for improved stability.
Using a rotating dish is less common, in part due to reliability issues (the less expensive types are alleged to suffer from corrosion and the ingress of dirt), but mostly because the equipment is quite expensive.
As you can see from the lower-left picture, the mounting is an equatorial setup - rather like the fixture on decent astonomical telescopes. This is required because the satellites describe an arc in the sky. If you move from Astra 2 at 28.2°E to the older Astras at 19.2°E, you cannot achieve this simply by aiming your dish a little more to the right. You must tilt it upwards a few degrees.
While it isn't that difficult to make a mounting system to follow the Clarke Belt, it is harder to make one that is precise and reliable in all weathers at any time you require it. For example, if you have a telescope and you tell it to "Go to Betelgeuse" and it misses, it is only a minor inconvenience as you can nudge it into the right place using the positioner controls. Most telescopes will follow a celestial body through the course of a night. I wonder if it'd be pointing at anything at all if you left the telescope outside for a year, to look for Sirius at 8pm and then find Vega at 11pm. Would it be that accurate over extended periods of time? Recall you usually have to set up the telescope at the start of a session by telling it where a prominent star is. I ask this, because this sort of continuous reliable accuracy is what we expect of a dish positioner. That's why they don't come cheap!
The above pictures were scanned from edito/publicité in TeleSatellite (mars 2007), and edited to look good on this page...



The firmware in the receiver can be upgraded from a broadcast on a compatible satellite, or via serial link from something downloaded. From time to time additional features and problem corrections may be made available. Failing that, a third-party may release firmware with various enhancements, which might be of more use if your dish is pointed to a satellite offering a bunch of subscription channels which are known to have a lame encryption system. Before you ask, this does not include Sky...
Selecting how to upgrade.
Selecting how to upgrade.


Upgrades? Help!

On the Silvercrest website (not the Comag website) there is software to read the firmware and channel list from the receiver and edit the channels and various aspects of the receiver setup. There is also software to burn the 'latest' firmware, which is also provided - but interestingly it seems a smidgen earlier than the firmware available in my receiver...

Don't contemplate the picture above - evidently there is no software that talks to the receiver using the nice obvious interface. Instead, you read/write/burn the firmware using a soft of 'back door' provided within the serial interface. Don't ask why...

Problem! The AliEditor software (download firmware from receiver, plus edit channels) does not work - this is because the receiver appears to spit data at 115,200kbps (i.e. as fast as most serial ports go) with absolutely no regard for flow control. My computer is a 466MHz Celeron machine (FSB 66MHz) with a standard on-board combo serial port. It isn't zippy enough to capture data at 115,200kbps, under Windows 98SE or DOS.
However, it did work on a 450MHz PentiumIII system running Windows XP. I think this is less to do with differences between W98 and XP, and more to do with the apparently-slower machine having a front-side bus clocked at 100MHz thus offering a throughput roughtly twice as fast as the other computer.
If this is how the receiver operates, I don't plan to try a firmware update!

I have written some software (for DOS) to attempt to talk to the receiver and read the firmware. Source code is available so you can have a fiddle with it yourself, maybe rewrite the serial handler for better performance - does anybody know how to allocate and write directly into a 2Mb EMS/XMS block? (more details)
Of course, if your machine can keep up with the serial transfer, there's no problem!


The back panel

Not only do you get the usual dual SCARTs (with CVBS or RGB or YUV outputs), you also get a separate CVBS (Composite Video, Blanking, and Sync) and audio outputs.
Not good enough? How about S-video (Y/C) and digital audio - as either co-ax or optical.
Here's the back, with descriptions:
The back panel, annotated.
The back panel, annotated. (click to download a bigger version)
My receiver is not twisted laterally, that bending effect you can see across the top panel is due to distortion in the camera lens.


Stuff I wish the SL65 could do...


If all else fails...

There's a snakes game, othello, and the infamous Tetris... Awesome!
Playing tetris - that piece will fit nicely in this gap...
That'll fit nicely in here...


Next: (Geeky!) Inside the SL65 (Geeky!)...


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Copyright © 2008 Richard Murray