There's an old couch potato's koan that goes: in the future, we'll probably be too busy watching the telephone to answer the TV.
But while it's all very well to rave on about converging technologies, back here in the predigital TV-room, even with all the menu-driven features on the latest VCRs, few of us can get a firm handle on the timer-record function, let alone the full mysteries of the rubbery punch-button candybox of the average zapper. Come on, wails the sofa spud, this is f*!£&*%$* leisure time.
Videoplus
Videoplus, of course, is the most spectacularly successful stab in the user-friendly direction; a smart little algorithm (which is far easier to decode than to code) converts date, channel, start and finish times into a three- to nine-digit number, which you simply dump in (still a bit of discomfiting headup, head-down squinting at the tiny italicised numbers in the listings pages) and the nice friendly machine has it sorted - except for maybe riffling on the end-record a few minutes, in case RTE is running late again.
The shifting of the pre-set channel-mapping positions due to Channel 5's launch in March was a bit of a headache (hands up who has reset their RTE positions yet?), and another reminder of how British manufacturing standards dominate our little market. But the basic Videoplus system works well, and looks set to survive the looming digitisation of TV.
Dreamt up in Los Angeles by two Hong Kong-born immigrants, it arrived on the US market in November 1990, as a stand-alone device which ingeniously bypasses all the different VCR programming protocols. It shifted 300,000 units in its first month, and arrived in Ireland (via the UK) a year later.
Today it is symbiotically hardwired into machines in 400,000 Irish households. Analagous to the dominance of Microsoft's Windows and DOS operating systems, it's an absolute standard in the smarts of over 50 million machines worldwide.
Even more spectacularly, Gemstar, which markets it, skims a licence fee from manufacturers (over 85 per cent of current models, the cost naturally passed onto the consumer), broadcasters, and the TV listings in newspapers, magazines etc.
More recently, Gemstar has developed onscreen programme guides (now incorporated into some Philips, JVC and Mitsubishi machines), analogous to the shortlived StarText feature on some Ferguson VCRs, which enabled you to program the video directly from the teletext TV listings with a cursor.
Programme Delivery Control
But Videoplus cannot deal with the problem of rescheduled programmes. Enter Programme Delivery Control (PDC), the latest feature to wet the lips of electronic-store sales assistants - but which digital television will make redundant.
So far, it hasn't become a great selling point (though it's installed in many new top-of-the-range models). Even so, it's a handy timer-record system which uses hidden codes sent by the broadcaster through the teletext to ensure you get the whole programme, and nothing but the programme.
If a show starts late or early, your VCR will override its own clock-setting and start recording when it picks up a PDC data pulse which signals the programme's beginning. The signal also informs your VCR to stop recording as soon as it finishes. So, say, if the match starts late, you don't have the dismaying experience later of having to fast-forward through some documentary on the sticky mating habits of the longhorn beetle - and then missing the two goals in the game's closing minutes. Broadcasters using PDC (currently only Channel 4 and BBC 2, which still classes it as an experimental service) assign every programme with a unique Programme Ident Label or PIL, a code which specifies the channel, date and starting time.
This data pulse is sent just before the programme starts, and then once every second for the duration of the programme, which keeps the VCR recording. When the show is over, C4 merely discontinues the signal, while in a slightly, different set-up, the BBC transmits a stop signal - although some little time after the programme ends - which ensures that you tap the trailers, but sometimes disrupts the timer-recording of consecutive programmes, due to overlapping PILS.
Unfortunately, a PDC video continues taping through commercials. The technology does exist to break the recording with an agreed-on PAUSE signal, but (a) it might create more work for the broadcaster, and (b) it might offend advertisers - some of whom happen to be VCR manufacturers.
If you wish to PDC time-record overlapping programmes, priority is given to the PIL of the show already taping - PDC works on a programme-to-programme basis, so to record two consecutive shows you have to set the PDC for each one individually.
If you adjust a TV's vertical hold, you'll see a black band with rows of twinkling dots - the "Vertical Blanking Interval", wherein the teletext scanlines are transmitted. Each teletext page contains a number of lines, each sent as a discrete packet of 40 bytes.
Who does PDC?
Channel 4 was first to install PDC in Britain, in 1994, followed by BBC 2 in 1995. A PDC service for BBC1 was advertised on Ceefax p697 (the PDC info page), but there's no longer any mention of it. The main problem is regional opt-outs. Extra equipment would be needed to deal with a separate PDC Service for, say, BBC Northern Ireland with its own programmes and time shifts. The ITV companies are planning a network-wide PDC system with regional opt-outs, while Channel 5 broadcast a full PDC service from day one.
At present, RTE has no immediate plans to implement a PDC service although the Aertel team is aware of developments in this area. However chary of the costs involved, they will be looking into it at the upcoming biennial conference on TV technology in Montreux. Meanwhile there are more pressing items on their agenda, such as the development of their interactive teletext service (a phone in one hand, a zapper in the other)..
The future
Although it has yet to be ratified by the European Broadcasting Union, PDC is a European standard which was set out in 1992, and the service has been available from public broadcasters in Belgium, the Netherlands, Finland and France for some time (Germany uses a variant called VPS - Video Programming System).
But it is only slouching towards any real kind of industrial acceptance. Minor differences in the way broadcasters have implemented it - and the programming protocols of different manufacturers - have created glitches. Some models continue taping for a short time after a programme has finished, getting ads and trailers - or worse, when taping two programmes in a row, snipping into the opening credits of the second programme - particularly on BBC 2, which uses overlapping PDC codes, unlike C4. (Also unlike C4, there are no ads, so programmes are closer together).
Other problems arise due to the way Channel 4 first implemented its service (without a stop signal). Some manufacturers programmed their machines to keep taping for a while after the PDC pulse has lapsed, lest it be lost temporarily, or in case "the programme comes back" - like an ITV film, broken by the News at Ten. Another horrible gremlin surfaced (but has since been remedied) on Channel 4 when a programme ran late: the VCR would record for 30 seconds, then stop for 30 seconds, then record for 30 seconds, ad total irritatum.
At this stage, it is difficult to tell what kind of life PDC will enjoy, before digital television renders it redundant in its current form. In the meantime, long live the new digital flesh.
For a more technical account of PDC, try http:// www.users.dircon.co.uk/ bandc.a.wiseman/625/pdc.htm
Mic Moroney is at: micmoroney@hotmail.com
Coded messages
A PDC pulse contains the programme's identity label (or PIL) plus other information such as a hexadecimal number for the country, TV channel, date, start-time, etc.
Other PDC codes are like impossible dates or times. 31:63, for example, is the Timer Flag, which forces the VCR to revert to its own clock setting. "Stop recording" is 30:63, "Pause" is 29:63, while 28:63 is "Unpause".
Another code is the Programme Indicator Type (PTY), a tag for designating a type of programme, or even a particular series - so that if you're out of town for a week, you can record, say, all science or sport programmes. C4 designates episodes of Brookside as PTY number 81, the Brookside omnibus as 82, C4 News as 83 and so on. There's also a sobering Alert code, for recording any news-flashes or announcements of national emergency.