freeview box query

[Arch]

My Mum got a Digibox/freeview box thingy for Xmas from my sister and brother-in-law. He set it all up and it was fine for about a month, then it stopped working. Mum said it felt hot to the touch. She's got it replaced ok, no quibbles, but hasn't got round to setting the new one up - I think she wants someone on hand to check it's all connected right. My query is - could the original going wrong be down to it sitting on top of her VCR? I mean literally, sitting on the casing. That's how B-i-L set it up, and I'd assume he'd think of that, but I just wondered, seeing how a VCR has a big magnet in it... Obviously, we don't want to repeat that if so. I know they are 'set-top' boxes, but I'm not sure if TV's have the same sort of thing inside.

If it is that, how far away should it be? IE, if we construct some sort of shelf over the VCR, how much clearance is needed? Mum has lots of films and stuff recorded on video, so wants to keep hold of it.

Also, the old one never had good reception for BBC4 - the picture and sound would freeze and jump. Is that an aerial thing? Annoyngly, it is BBC4 my Mum would most watch...

 

[Gerry Attrick]

Putting the box on top of the VCR should not cause it to fail providing nothing is blocking any ventilation ports. My box has sat happily on top my dvd recorder for a number of years without problems.

The freezing/jumping picture is likely to be poor reception for that channel. Most set top boxes have a facility to check the signal strength of each channel so you could check the instructions to see if yours does. Solution is maybe an uprated aerial or a signal amplifier, neither of which is cheap. Some areas have an inherent problem receiving some stations so a chat with a local supplier may help.

 

[Sh4rkyBloke]

^^ What he said.

 

[Amanda P]

I wouldn't have thought sitting a digibox on top of a TV or any other TV-related gadget would be a problem. It should be designed for just that position anyway - that's how it's going to be used.

The BBC4 thing - I have a feeling that some digi stations (especially BBC ones) are available on more than one channel. Most digi boxes have an auto-setup function that scans through the channels available and programs the first instance of each station it comes to. If the first one it comes to is a bit weak, it might be better (after it's finished running the auto-setup) to run through manually and see if there is a better "version" of BBC4 on a channel other than the one the auto-setup has chosen, then program it to use the better version.

Or that might be bollocks because I'm thinking of analogue TV...

 

[Arch]

Cheers all. I'm at a bit of a loss, me only having black and white anyway.... Looks like she just got a duff one to start with.

 

[fossyant]

Don't forget you'll often have to re-scan as they shuffle the channels about.

 

[marinyork]

Give it as much airing as possible. STBs tend to overheat very badly. Unplugging them from the power and giving them as much air as possible and not blocking vents mitigates this.

As Gerry Attrick said you want to find out what the signal strength is on the different channels. Unfortunately there's no way of telling you how to do this as they can be quite different but one of the standard software bundled has it as a white bar when you change channel.

BBC Four will be the only one affected as on freeview on that particular multiplex ( there is mostly radio stations, interactive, CBeebies, BBC Four and BBC Parliament. It is unusual to have a problem with B though as it's usually a higher power rating.

 

[Ghost Donkey]

I'll second what Gerry Attrick said about temerature/ventilation. YOur VCR won't kick out much heat when it's not being used. The old box was probably just faulty. Electical equipment tends to go at the beginning of it's life or aftera lot of use from wear. Don't get me started on extended warranties.

This is all from my hazy memory but if it helps... VCRs don't have a big magnet in them. If they had a magnetic field big enough to damage the equiment sat above it the tapes you put into it would be effected as they moved through a large magnetic field. We used to use a magnet tape degausser where I worked to do just that. The magnetic field is induced via the write head which is tiny and spins on the head drum. The tape floats a couple of thousands of an inch (in old money and varies with tape format) away from the head drum on a cushion of air created by indents following the line the head drum spins. The tape on a VHS VCR wraps most of the way around the head drum and the magnetic domains on the tape are quite sensitive. It's a relatively small magnetic field as it needs to affect one video line of information per head passing the tape. It works in reverse for reading the tape where the organisation of the magnetic domains on the tape moving through a magnetic field induce a voltage in the read head which is basically a picture line.

When you try and retune you usually get results relating to how many channels are found at each frequency as it is scanning/tuning. With BBC4 you may find other channels have the same problem. They are usually grouped together on certain frequencies. The traditional aerials were often "tuned" so that they aremore sensitive to the frequencies used by the transmitters in your area. With freeview the frequencies are often spread out across a larger range so a wideband aeriel may be benificial. It may not be beneficial either where oyu live. Nice and helpful of me there then .