As a nice bonus this weekend I got given some MDFS hardware – this was a standalone setup which ‘talked’ Econet Level 2 and Level 3, so you needn’t run the FS on a Beeb. There’s some pics of SJ Research MDFS stuff over on Chris’s site, and a more thorough rundown of what it was over here: I’ll use it to replace the A4000 doing the L4 file server probably.

I’ll take some pics and get it all working when we’ve got Ellie’s birthday done with.

Given the service manual arriving and a day away from the Beeb heap in the garage, I was absolutely champing at the bit to try and get the Domesday system working. After finding the focus error, the service manual suggested cleaning first (easy), or replacement of the focusing module (pretty much impossible). I’d got a few photography-grade cleaning buds in my lens bag so that seemed like the first port of call; goodness me, the muck that came off that lens, all that grease and dust – it’s a wonder the sodding thing hasn’t got more in it. Anyway, that cleaned, I powered it up with the debug codes on.

I’ll be honest with you, I wasn’t expecting it to work! Thus I was really pleasantly surprised when with a ‘rumble’ the disc span up. It seemed quite shaky on its bearings and spent 2-3 minutes ‘focusing’ and recalibrating itself, and eventually I shut it off again thinking it was still bust. Bring it up to read the POST codes some more and – well I’ll be damned, I was rewarded with the intro video from the Community Disc on the screen.

A quick bypass of the CUB monitor that the Beeb was showing, and this was the result. Hooray!

Power-down of the LV player to get rid of the POST codes, and it came back up no problems. No shaky disc, no problems reading, I spent the next ten minutes trying each side of both discs in turn which worked fine. It even showed the video on side 4, and searching worked fine. Now this is important, because in order for the computer to allow searching, almost everything needs to work – the SCSI card, the Master AIV, the 65C12 coprocessor inside the Master, the genlock (which is apparently one of the more frequent things to go pop) and the LV player itself.

All is not completely happy though – we still have no sound. There’s a very slight ‘fzz’ in the speaker when the audio is meant to get to a higher volume, and if you switch off either audio channel you get a satisfying ‘pop’ from the audio as it cuts in and out. This is leading me to believe it’s something as simple as a popped bit of the amplifier circuitry, which should be trivial to fix from the service manual.

If you’re curious, photos are here. There will be more (and some screenshots) once I’ve fixed the sound, and I’ll try and encode the video too.

I’ve not done a lot of Beeb stuff recently, primarily because the garage has been in such a state it’s been impractical to work in there. However with Christmas gone I can clear a lot of the junk out and that’s given me better access to the Domesday system I acquired late last year. Plus I was in a bit of a stinky mood last night so decided to have a crack at getting it all going again.

Having fixed the monitor, I was confident that I might be able to fix the remaining non-worker! The Philips VP415 laserdisc player is a notoriously cranky piece of kit famed for failures and overheating; since the videodiscs themselves loaded fine and it seemed to try and spin up I was in a pretty bullish mood as I connected it all together and switched the BBC Master AIV unit on.

Uh-oh. Click click click. Something’s resetting the BBC Master computer repeatedly. Disconnect everything, retry, click click click. Traced it down to the PSU which had blown (and thankfully I have some spare BBC Master units I could strip one from) but still a bit of a heart-stopper moment – the SCSI interfaces in those are like hen’s teeth.

So back to the LVROM: nothing on the screen at all, and I still couldn’t find a service manual! I’d already asked on the BBC Micro mailing list with no success last year, but I thought I’d give it another stab and within 10 minutes I’d got two replies telling me about Mauritron who sell service manuals as PDF files! Hurrah! One debit for a tenner later and I was waiting.

This morning the manual arrived by email. It’s taken me five minutes to put the LVROM into service mode and got an onscreen result error code ‘007’ meaning ‘Not in focus after 5x (no rotation of disc)’. Now this could be one of three things: the focus module, the control module, or the decoder module. My money’s on the focus module, which may (fingers crossed) just need a clean.

As a side-point, at least the debug info appearing on-screen indicates that the video circuitry is working and the monitor works too. There’s still a thousand things that could go wrong yet but I’m quietly optimistic 🙂

OK, i’m going to promise right now I won’t blog about this on a daily basis like I did with the Econet, but I’ve been asked a few times about this so here’s the update.

Easy one first: I removed the monitor switch from the equation and now you need to turn it on/off at the plug, but it works.

Now, there is a fault with the Philips VP415 player: it powers up OK and appears to work, but when a disc is inserted it won’t spin it up. If I put it in ‘replay’ mode, it will ‘jerk’ the disc as though it’s trying to spin, then stop. At that point it beeps and the red standby light flashes (indicating an error maybe? I have no manual for this unit). I need to acquire a service manual for it really then I can test it properly. And I need to buy a new multimeter, since mine’s gone walkies.

In any case, the Master appears fine, and the discs appear OK too – that’s part of the battle, I might still be able to find a spare LV player from somewhere (they were ‘hacked’ from a fairly popular Philips range I think, so some of the bits will be cross-range I guess).

More anon.

Last night I acquired a new toy: a BBC Micro Domesday system, complete with laserdiscs (LVROMs), trackball, monitor, trackball and manuals. It’s been sat in a cupboard in a school for years, but almost works.

What needs doing:

• The laser needs re-tracking on the LVD player itself – apparently it has issues reading from the disks. This isn’t a big job I don’t think unless the servo itself is gone, but I’m sure I can source parts.
• The power switch on the monitor needs fixing – looks like the catch on it has either bust or come off. Not a big job.

The ROMs themselves appear in good state, as does the Beeb. I shall attempt to power it up over the weekend and get it going properly.

Update: More about the BBC’s Domesday Project here, and some info on CAMiLEON (the preservation of the Domesday data) here together with a photo.