New Dedicated hardware For RO64 - speculations
Rick Murray (539) 13806 posts |
Ah, but the wonderful world of open source means that if one thinks they can do better and can rope together enough like-minded people… fork it and do it right.
I think it’s a rather specialised topic. But, then, so is UI design and look at how they bugger around with the UI in each major release of, well, anything. That’s one of the good points of RISC OS. The biggest “Oh! My! God!” in our little UI was when somebody added rounded corners. We haven’t had the icon bar go to the top or side of the screen, or menus get replaced by a menu bar, or the window control icons arbitrarily move around because somebody felt “toggle size” should go beside “back of stack” and “close” over on the right… |
Rick Murray (539) 13806 posts |
Since this is Aldershot… ;) First of all, it isn’t witchcraft. It’s just some really basic maths. Secondly, satellite finders are shit, don’t use them. I got mine bleeping like crazy pointing my dish at the ground. What you should do is if it’s a Sky box, set it to the signal strength meter (this is also the default channel with firmware and regular EPG data etc). If it’s a Freesat box, probably the same. Once you have set that up, find some sort of TV and put it in a position where you can see it as you wibble the dish around. The dish itself should be tight enough to stay put, but loose enough that you can reposition it. Move the dish using only the support structure at the back. Never pull the dish itself or the LNB arm. But you know that, right? Now, there are three things that you need to do. Left/right position. You need to locate south. At a pinch, this is where the sun is at noon in winter time. Adjust for your timezone. Now imagine a line going south. And another line going to the left (east). That’s 90 degrees. Divide it into three, then move the dish to point almost to the first third (but not quite). Up/down position. You want to be pointing at satellites that are floating in the far extremities of the atmosphere over Egypt or something. As the earth is curved, this means that the up/down angle is important. Dishes in Scotland appear to point towards the ground, mine points higher up than any in the UK. Note that most dishes are offset. That means that they do not point directly towards the satellite. You can tell this because the LNB is on an arm to the bottom and not directly over the centre of the dish (like it is for a radiotelescope). For the UK, the elevation should be around 21 to 27 degrees. Again, don’t worry if you aren’t bang on target. The final setting is skew. Leave the LNB a little loose in its holder, we’ll come back to this. It is better to see a TV rather than use a meter. Why? Easy…
It’s a crowded sky, so a TV will show you if you’re pointing at the right thing. A meter won’t. Now, using either BBC 1 as a guide or the signal strength meter, slowly sweep the dish back and forth for a few degrees either side of where you have pointed it. If it doesn’t work, adjust the elevation a little and try again. BBC One London / EPG test are strong signals so you ought to start seeing something even if you aren’t bang on target. Adjust until you get the best reception. Now select a weaker channel such as Legend and verify that this is correctly received. Now select one of the extremities such as Film 4 and verify this is correctly received. If it is not, before you fiddle with the dish, check that it is set up correctly (specifically, is the LNB type 9750/10600 or 9750/10750?). Finally, you will want to adjust the skew. This means to rotate the LNB slightly clockwise when looking at it from the dish. Try around 12 degrees. You should see this change the signal quality reading. Adjust until it’s the best quality you can get. Now bolt everything down. Job done. My dish isn’t properly fixed in place as the dish support slips over a dish mounting pole fixed to the side of the barn, and there’s no clear way to tighten that up. I suspect jubilee clips and some bits of metal between the two sides. But, honestly, as long as I don’t get strong winds the weight of the dish keeps it in place. And if I get strong winds? I just go and poke the dish with a long pole until I see CBBC (if that comes in, so does everything else). It’s not wizardry or magic. It’s not even complicated maths. It’s just faffing around until it works. |
Glenn R (2369) 125 posts |
[detailed instructions snipped] You forgot to add the words “whilst chanting the magic incantation” and “after ritually sacrificing the requisite number of small furry animals”. Not goats though. Goats are for SCSI. It’s one goat for every device on the SCSI chain. Remember that otherwise it won’t work.
The el-cheapo ones probably are. The professional ones however will lock onto the transport stream from the default transponder and display which satellite (or cluster) you’ve pointed at alongside the signal strength. But this type costs… a lot. It’s not the bargain basement type that Maplin used to sell for 20 quid.
Which explains why you’ve become something of an expert at DIY re-alignment. :-) Mine’s fixed to the rear wall of the house (between the bathroom and spare bedroom windows, and well outside arm’s reach from an opening window) as high as possible. So fixed to a solid brick wall, just below the eaves of the house (and sticking out far enough so the signal isn’t obscured). I had to get it re-aligned just under 2 years ago after the Polish scaffolding contractors moved it (the scaffolding went up when the solar panels went in) and didn’t bother to mention it. Fortunately the solar contractor was fine about it, said to get it re-aligned and send him the invoice and he’d reimburse me and claim it back from the scaffolders. It cost £50 – not a lot when you think a bloke had to come out in a van, set up a ladder etc. My dish is about 50 feet off the ground and I’m no good at height, so it’s not something I could have done myself. I don’t have $ky these days, but the dish dates back to $ky days. Got way too expensive and I realised I was mainly watching either the Freesat channels, documentaries or movies. A quick calculation showed that if I could forgo the documentary channels I could just subscribe to Lovefilm and get blu-ray rentals (and unlimited streaming) for £10/month instead of paying nearly £50/month to Sky. 6 months later I cancelled Lovefilm when I discovered that £10 would get me a fair few second-hand blu-ray movies from CeX. So I switched to Freesat+HD instead. Now my quandary is how do I get more than 4 outputs from the LNB? A Freesat+ box takes two, so I have a pair going to the living room and a pair going to the master bedroom. I vaguely remember something about splitters; I’d intended to pop in to the satellite specialist (who used to be an Acorn dealer, just to keep on-topic) for advice, but driving past the other day I discovered he’d retired and the retail unit is now a pet shop. Ah well. A bit of research showed you can get an octal LNB which would solve the problem as then I could run another pair of downleads to the spare bedroom and small bedroom. The TV in the spare bedroom has FreesatHD but not FreeviewHD, although I have it hooked up to a Freeview+HD/Blu-ray combi unit (bought for peanuts second-hand). I also have a FreesatHD Blu-ray recorder but presently nowhere to connect this (got it for free as someone had moved house and no longer had a dish). I’d like to put this into the small bedroom (that I use as an office), that way if something is on that I want to keep I can record it onto the HD and copy to blu-ray. But that would involve having an extra pair of satellite feeds to the small bedroom. EDIT: I’d imagine replacing the existing quad LNB with something like this would work: https://www.amazon.co.uk/GeoSync-Universal-Satellite-Freesat-Receiver-Octo-LNB/dp/B0B9HLL74C?th=1 Maybe drop a couple of extra runs of CT100 cable when I’m doing the flooring in the back bedroom and leave enough slack to be able to fit this at a future date? |
Grahame Parish (436) 480 posts |
When I moved in here there was a Sky dish in situ already. Luckily it was used with SkyQ so it has a wideband LNB. The Freesat recorder will record up to 4 channels at once – and simultaneously too :) so my recorder went from 2 channels to 4 for nothing. The TV is Freeview & Freesat, and I really want to switch to Freesat on it to save the regular retunes, but doesn’t work with wideband LNBs, but there are hybrid LNBs with wideband (2) plus standard (4) outputs which might do what you want to do. I’m hoping to get mine swapped out soon. An example here |
David J. Ruck (33) 1629 posts |
The magnetic variation is current less than a degree in the UK. No need to remember “west is best and east is least” when doing the flight planning these days. |
Rick Murray (539) 13806 posts |
No, no sacrifices needed. Your problem, as is often the case, is that your dish is damn near inaccessible. You know, for the first few years I was out here, my dish was on the ground held in place (and propped up by) some spare ridge tiles.
Which is a lot of money to spend when putting the TV visible will do all of that for free.
Do it a few times, you get to have an idea of “where” it should be pointing.
<gets phone, translates that into international measurements>
I cancelled my Sky back in the analogue to digital switchover. I think the final nail in the coffin was yet another price hike, and I was watching Letterman on Sky 1 and they managed to stick adverts in between the start of the programme and the opening sequence. Like, why am I paying so much for this? These days, Netflix / Prime Video. The latter is kind of crap (far too much stuff where they have ditched the original English audio in favour of a French dub of varying degrees of naff) plus one of the most awful UIs I’ve ever seen… but given I save more in “free post” than Prime costs me, it’s basically a freebie that I don’t pay that much attention to. Especially now they’ve gotten greedy and started inserting advertising.
Mine’s a generic dual output (Sky Plus?) model from Lidl many many years ago. My receiver only needs one input, however it can dump the transport stream to harddisc and that can be played with MPlayer/VLC (on the PC) or SMPlayer (on Android). But, then, it’s just me and I don’t need anything fancy like recording one thing while watching something else. Usually I use my !Tea app to set up recordings, and maybe watch stuff some time later if/when I remember. I dunno, the idea of sitting down to watch something at a particular broadcast time seems… kind of quaint. I remember people used to organise their entire lives around either Neighbours or The Chart Show (when I was at school) and just after I left the big thing was Twin Peaks. I will admit, however, when Netflix released Wednesday I did watch it all over two nights. And when Prime released the first three seasons of The Expanse, I marathoned the lot in about a week.
The joy of peacefully sleeping on top of churning molten iron… |
Stuart Swales (8827) 1349 posts |
Mine is mounted on the garage fascia board. When it snows, I can toddle over and push the snow off the LNB support. Unlike other folks on the hill, who have them chimney-mounted. One used to have to get a ladder onto his mezzanine roof, then another tall ladder up from there to the gable end. No, no. Had it installed by Sky for nowt in 2003 with cheapest available monthly sub, then went FreeSat after the first year. Analogue TV signal here was piss-poor, 2W repeater a few miles away with line-of-sight densely infested by trees. |
Chris Mahoney (1684) 2165 posts |
I went to the States in the 90s, found Fox and sat down to watch The Simpsons. It had the usual opening sequence, then cut to ads before the actual episode even started. I was astounded. These days I don’t even bother with broadcast TV. There’s enough of amusement on YouTube. |
Clive Semmens (2335) 3276 posts |
I was a research assistant on this project in the mid-1970s: https://www.28dayslater.co.uk/attachments/dsc_0136-jpg.83518/ The software side* of aiming this dish & recording the signal data was my job: https://www.28dayslater.co.uk/attachments/dsc_0142-jpg.83516/ With the rather tighter reception angle than domestic satellite dishes, it had to actually follow the wandering of the “geostationary” ATS6 satellite. Or for more pics & a bit of blurb: https://www.28dayslater.co.uk/threads/oxenhope-radar-station-29-11-07.23763/ * Using a PDP8 computer, only fast enough for the job if written in pretty tight assembly language. Core memory size also an issue. |
Glenn R (2369) 125 posts |
This is true: Ignore the mess – I’m in the middle of having the garden re-landscaped.
A rough guess. Someone can probably calculate by looking at the photo above.
I didn’t get $ky until early 2000, basically when they were giving away the free digiboxes. Half-price installation (£20 instead of £40) if you took everything (movies, sports etc), but I cancelled all the premium stuff after a couple of days. Between 2000 and 2009 (when I cancelled it) the price had gone from £15/month up to about £35. I was also really disappointed when Sky Digital went in that, when flicking through the music channels, there was no sign of CMT Europe. I later found out it had closed down about 18 months earlier (just before digital launched).
Both my receivers (Samsung) need two inputs. Which takes up all 4 outputs from the current quad LNB. I don’t think they’ll work with wideband LNBs either. It would just be nice to be able to hook up the Freesat+ / Blu-ray recorder, and use the Freesat input on the spare bedroom TV for HD. Comparing say BBC1 HD on Freeview to Freesat, the Freesat picture is noticably better. As an aside, all the “go HD” propaganda back a few years ago was extolling the improved picture quality over SD, but unlike the jump from VHS to DVD, SD to HD (in PAL countries at least) isn’t a huge leap, more a gradual improvement. However, the improvement in audio quality between SD and HD channels is a big jump. SD channels use the MPEG2 layer 2 (MUSICAM) codec for audio. HD uses either AAC (MP4), AC3 (Dolby Digital) or EAC3 (Dolby Digital+). (Yes, I know Sky+ had AC3 audio on the movie channels, but that was a proprietary extension and not part of the DVB-S spec, whereas it is part of the DVB-S2 spec.)
I did see a little clip of it, but to me, Christina Ricci is Wednesday Addams. |
Clive Semmens (2335) 3276 posts |
Fifteen feet about… |
Glenn R (2369) 125 posts |
Looking at that photo I’d say 20 feet. The dish is mounted just below the eaves. It had to be done that way as at the time of installation, next door had a couple of tall-ish trees in the garden (which they’ve since had cut down). I’d still want the dish high up though as it avoids it being accidentally knocked. If the dish is ever at the front of the house (particularly if the building is on the walking route back from a local pub) then always remember the “two drunks high” rule; ie one bloke standing on another bloke’s shoulders shouldn’t be able to reach the dish. In practice this means mounting it at least 12-15 feet above ground level. |
Clive Semmens (2335) 3276 posts |
Yup, 15’ is a low estimate. 20’ is probably a bit high though. I can’t be bothered to count the bricks! The ceilings in the house are probably 8’ or 2.4m, there’s probably 220mm between the downstairs ceiling and the upstairs floor. The tops of the upstairs windows are probably 200mm below the upstairs ceiling. Downstairs floor will be level with the bottom of the patio doors. |
Paul Sprangers (346) 523 posts |
22.5 feet (I did bother to count the bricks – 63 to the middle of the dish.) |
Clive Semmens (2335) 3276 posts |
63 bricks is 15’6" according to my book… |
Rick Murray (539) 13806 posts |
Between 5 and 6 metres. That’s much more realistic, and I have a three section extending ladder that can manage that.
Did you account for the gunk between the bricks? ;)
Yikes.
Depends if that’s regular HD at 1280×720, which isn’t that far off 720×576, or if it is 1920×1280 which is a huge difference.
That’s because video tape is spectacularly poor really. Something like 300-400 lines, flattened colours, noise, and until HiFi audio came along it was an audio track that was so bad it’s a wonder anybody tolerated it. There’s a reason why vinyl is still around in the digital age, while the writing was on the wall for VHS pretty much as soon as we got tech that could record video digitally.
Watch it, re-evaluate. For starters, they finally get the ethnicity right.
Except by avian wildlife, perhaps.
So glad I live in the middle of nowhere. They being said…
There’s a part of me that would like to see this. Just because somebody is stuffed full of alcohol doesn’t make stupid become possible. It just makes it hurt less until the effect wears off. Then they understand why it’s only trained cheerleaders and gymnasts who do that sort of thing in real life. |
Clive Semmens (2335) 3276 posts |
Of course. The book is a standard text on building construction in the UK, that I’ve used when I’ve been building things like porches and sheds. It’s a bit out of date on the building regs, but those are all online nowadays anyway. Standard bricks are 65mm high and have 10mm mortar between them. |
Glenn R (2369) 125 posts |
I did this check on my old plasma (Samsung 51" full HD). Jumping between the SD and HD versions of BBC1, well yes, the HD picture looked a bit sharper, but not a dramatic difference. On the other hand, I had an NTSC version of some movie (I can’t remember which one now so don’t ask) that I also had on Blu-Ray. Going from a 480i to a 1080p version was quite dramatic. I’m guessing the extra resolution on PAL makes the jump from DVD to Blu-ray a lot less. 576i to 1080p. Again, comparing PAL DVDs to Blu-ray versions of the same movie, the improvement in picture is gradual. The biggest difference is the audio. Blu-ray supports lossless audio, and whilst Dolby Digital (AC3) becomes transparent at bitrates of 640Kbit and above, DVD would only support bitrates up to 480bit. DTS is transparent at full-rate (1.5Mbit) but only music or demonstration DVDs had full-rate DTS. Most movies used half-rate (768Kbit). Blu-ray gives you either Dolby TrueHD (lossless) or DTS HD-Master (lossless). Also remember that Blu-ray movies (from cinema sources) run at the correct speed of 24fps, PAL DVDs speed up to 25fps which causes a semitone increase in pitch. NTSC does use 24fps, but with 3:2 pulldown so horizontal motion is juddery and stuttery. (My new TV appears to be able to remove 3:2 pulldown, and de-telecine the video, showing it at true 24fps.) Although when ripping Blu-ray movies I tend to just leave the DTS soundtrack in place for HD-Master discs, or for TrueHD I re-encode to Dolby Digital+ (E-AC3) at 640Kbit. It’s transparent but saves a fair amount of space. That said, the difference in picture quality is more noticable on my new TV (65" 4K OLED). Standard-def material is still acceptable though, provided the bitrate is high enough. All the DVD rips of the David Attenborough documentaries for example.
Try 200-250 lines on standard VHS (note that “lines” aren’t the same as scan lines, this will remain at 625 or 525 for PAL or NTSC – the ‘lines’ in question are to do with a standardised analogue resolution test and are horizontal), maybe 270 lines if you had a particularly top end VCR (my old Ferguson 3V43 could manage this), or ~400 lines on S-VHS. The biggest problem with VHS was the way the chroma signal was recorded. To save bandwidth, it was massively “downsampled” (in the analogue domain) and the chroma resolution is awful. The only reason it works at all is because your eyes are much more sensitive to luma than chroma, so as long as the luma resolution is ok then the picture is acceptable. S-VHS had a luminance resolution of around 400 lines (same as analogue broadcast TV) but the chroma resolution was no better than VHS. So it’s still possible to spot the difference between off-air and recorded material, even on an S-VHS machine. (Again, remember that “lines” is in the horizontal domain, not scan lines.)
Maybe. I just have a hard time staying interested in a series. The 1991 and 1993 movies were classics, and additional material may ‘dilute’ things. Look at how Disney have destroyed Star Wars for an example? The last long-form series I got really into was His Dark Materials. Which was awesome, but I have to say would have probably made no sense at all if I hadn’t previously read the books. Other than that I tend to watch maybe 2-3 episodes and lose interest. Whereas with a movie, it all fits into around 2 hours. (Except Lord Of The Rings of course, but there’s always an exception.)
It’s close enough to the eaves and wall that this isn’t a problem. Avian wildlife tends to perch on the gutter. And the bolts on the dish are tightened enough that a pigeon isn’t going to accidentally move it.
I’d be laughing too much. I think the Germans actually have a word for that. |
Rick Murray (539) 13806 posts |
It’s nice to be able to read the captions and credits.
I have no idea. The original trilogy is Star Wars, the end.
The Titanic movie. At the cinema in Bridgwater, the audience actually started cheering when the thing started to sink. Like finally here’s the part we came for…
Arschloch? PS: We have a perfectly functional word too: epicaricacy |
Glenn R (2369) 125 posts |
Well, there is that. I was thinking more of films made for the cinema, where although the screen is 40 feet across, you’re sat as far back from it, so in terms of the degrees of arc covered it’s like sitting 10 feet away from a 65" screen at home. (Obviously there’s other issues there too.)
Last January, my friend came over from Sweden for 3 weeks. She’d never seen Star Wars. We watched all 3 Star Wars films. Yes, I said that right. All three. The bonus discs from the 2006 DVDs. The ones that contained the original theatrical versions. Han shot first, and all that. Not in HD. Officially you can’t get the theatrical releases in HD. Unofficially… Let’s put it this way. I have a set of three MKV files sat on my media server with the theatrical versions of all three Star Wars films in 1080p with DTS audio. They were sourced from the 4k77 project (along with 4k80 and 4k83). The released files are 4K with several soundtracks and no noise reduction. Tried watching those on an OLED screen and the film grain was intrusive. I ran them through Handbrake, downscaled to 1080p with some fairly strong de-graining. The result was pretty much as perfect as you’re going to get from a film that’s nearly 5 decades old, where the only scan that could be made was from an unused theatrical print (third or fourth generation). No idea if the interpositive master for the theatrical version still exists, George Lucas claimed to have ‘destroyed’ it in the process of making the Special Editions. However I did have a chance to compare a 1080p re-encode of 4k77 to the official Blu-ray. The 4k77 version looks better. A lot better. No colour casts, Darth Vader’s lightsaber is back to its proper red colour rather than being pink, shadow detail is visible, no more crushed blacks. (The original encode did have a green colour cast, but that was because I’d not specified Rec.2020 colour space and the blu-ray player was just guessing incorrectly what colour space to use – I ran the encode again specifying the colour space and all was fine.)
Pluto is a planet. Referring to it as a “dwarf planet” is discriminating against celestial bodies with a lower mass.
I was thinking more ‘schadenfreude’. Defined as ‘pleasure derived by someone from another person’s misfortune’. Although “pleasure derived by someone from the consequences of another person’s stupidity” is probably a more accurate definition. |
Rick Murray (539) 13806 posts |
Whoosh! 😂 |
Glenn R (2369) 125 posts |
I’d had a long day when I wrote that reply. I’ll give you that one. |
DownUnderROUser (1587) 124 posts |
“But then, I’m also going to die on the hill that says Pluto is a planet, so I guess I’m just a grunpy old git….” Now in my 50s grumpy old git is a bit definitive. ݼ |
Steve Pampling (1551) 8155 posts |
Use that as a marker for very early middle-age and work from that. Leave the grumpy old bit on the back burner for a few decades. |
Chris Mahoney (1684) 2165 posts |
Fine with me. The Aldershot forum is, after all, not an official IAU meeting venue, and I believe that’s the only place where the “dwarf planet” designation is actually enforced. I’d have thought that a dwarf planet is still a planet, just like how a small cat is still a cat. |