T.V. Remote Question

[Bartc]

The rotary ones for the 13 or so VHF channels? I remember one with a button that you pressed and slid sideways to select.

This 17" TV I mentioned still had tactile electrical buttons which completed a circuit when pressed; but the lack of a microprocessor containing somebody's crappy, buggy code to slow everything down meant the tuner responded instantly (I think it used varicap diode tuning, so it just had to select one-of-eight).

Debounce circuitry surely is only only responsible for a few dozen milliseconds of delay. This is for solid metal contacts; maybe the higher Z soft contacts of some remotes may demand a longer delay, but I've been using remotes of some kind or other for a couple of decades and have never seen one this bad.

Maybe the V+ box has to send the command back to the cable company for further instructions. (And even if it did, surely it would know enough not to queue commands, as these rarely make sense for a system relying 100% on visual feedback to determine the next press.)

[michael adams]

There is no such thing as "conductive rubber".

The conductivity is provide by a graphite in oil solution which is what is used to coat the underside of the rubber pad.

Conductivity can be improved on the pad by rubbing the contact points on the underside with a soft graphite pencil such as a

4B or above.

Again the person who suggested cleaning the rubber pad with a pencil eraser - and thus rubbing off all the graphite simply doesn't have a clue what they're talking about.

< Yawn >

michael adams

[michael adams]

Oops!

Conductive rubber - rubber containing carbon spheres whose conductivity increases with pressure.

michael adams

[fictitious]

FFS...What have I started here? ..LOL

[Arfa Daily]

Yawn all you like, pal. I care not ...

Your contention that the undersides of the contact lozenges are coated with some kind of graphite-loaded oil, is imaginative nonsense.

Arfa

[Adrian C]

I'd say that's more of a symptom of the *receiver* not doing what it's being told. Some IR systems at the equipment end can take a small while to process commands, and also may discriminate from random presses using a similar delay to your description. And then some remotes are not so directional, some have faulty caps and dodgy battery contacts, and some hammer life out of rapidly dying or inappropiate batteries.

Hammering excessively on buttons is the equivalent of the misses overtightening the bathroom tap.

[Bartc]

Yes there might be a delay in synchronising to the data stream of a new digital channel (as it waits for a new i-frame in mpeg compression for example).

But the delays I've seen on Freeview and digital satellite have been small and only mildly annoying. Nothing like the V+ box used with digital cable, which can be impossible at times. It is the unresponsive of the remote controller and the box which is the main culprit.

[Jerry Brown]

Behold The Megatron: .

Jerry Brown

[Arfa Daily]

The LCD TV that I have in my kitchen when working on its FreeView tuner, takes fully five seconds to 'respond' to a remote channel change request, in terms of putting up the new picture. When it is in analogue mode, channel changing is near-instantaneous. OTOH, the digital sat box is as quick at changing channel as an analogue TV. Just as a matter of interest, how slow is the V+ box at changing channel ? I'll ask my mate who works for them on field service, if he has come across this a lot, and whether it is considered to be an 'issue' by them.

Arfa

[Tascam Holiday]

About 1mm/sec. But I think maybe you're confusing electrons and current. ;-)

[PCPaul]

On Sat, 14 Feb 2009 23:54:22 +0000, Arfa Daily wrote: Just as a matter of

It's crap. I was really disappointed with it.

There are two aspects:

- it takes a while to respond to the remote (sometimes several seconds, usually just 'a bit longer than expected'. It then queues up button presses so when it does respond it whips through doing things you didn't want it to do. This is especially noticeable when usaing the EPG, which uses such huge fonts you get page after page after page to scroll through but scrolling each takes too long.

- channel changing actually takes a while to sync up and change. Much longer than Sky+ or a cheap'n'cheerful freeview box.

I like the recording aspect of V+, but overall it's not that nice to use. I've designed and programmed a few user interfaces for work and the V+ interface responsiveness would have got me told to 'do it again, properly'...

[PCPaul]

0.02mm or less per second. But I think he's talking about switch debounce circuits, not electrons OR current...

There's also a thing in most IR setups where the control bitstream has to be received at least twice corrcetly before anything is done. Since the bitstream for a standard remote setup like RC5 takes 25ms to send and there's an 89ms gap between resends that means you've got *at least*

159ms before it even starts to respond to the signal. That's getting well into the perceivable delay range.

[Bartc]

When it's behaving itself, and the remote is right in front of the box, channel change is 3-4 seconds. Which is OK.

The problem is presses that don't register, combined with sometimes inexplicable delays in responding, compounded by sometimes pressing a key a second time not knowing whether the first press simply didn't register or it's just thinking about it.

Sometimes the box seems 'busy', like a PC that's just booted up: the icons are there, the cursor moves, but clicking anything takes ages because it seems to have other things on it's mind.

And many operations seem to require some sort of dialog with the cable company.

They could make things much better by having an audible beep for a keypress, and not stacking up commands until the first one has executed,

(And the scary thing about V+ is that the cable company could easily find out exactly what programs you've recorded, watched, and paused on!)

[Arfa Daily]

Well, that's absolutely standard these days. It's the reason that part of the Sky contract stipulates that the box must remain connected to a phone line. If you do dis it, they send you a letter threatening to cut your legs off at the knees ...

Arfa

[Bob Eager]

I suppose you have changed the batteries? Seriously, those symptoms (or some of them) can be traced to failing batteries.

[Arfa Daily]

OK. I've asked my oppo on Virgin field service about this, and he says that it is a well known problem, and that he gets calls about it all the time. There is nothing wrong with the box or the cable system or the remote control circuitry per se. It's just the way it is, so I guess that's basically 'wrong by design', and at this time, there is no fix for it. Not much use to you, I know, but at least it tells you that no matter how much you scream at them, it ain't gonna get any better ...

Arfa

[A.Clews]

You're not taking this seriously, are you? :-)

[Jeff Lawrence]

Of course! I always take not taking things seriously seriously. Cheers Jeff

[Man at B&Q]

In human terms that's as good as instantaneous. It has nothing to do with any delay in changing channel.

Debouncing doesn't have to introduce a delay in any case.

MBQ

[Man at B&Q]

It's the box, not the controller. I have a similar issue with a "Cello" DTV that takes ages to do anything. It's more likely the embedded processor is not really up to the job.

MBQ