recorded tv still freezing and jumping

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OK some history first. Previously had a Humax pvr and crt tv. Recorded programmes started freezing and hoppity skipping. Got new aerial with masthead booster, new digital tv and new hard disk recorder. Both Panasonic.

Some problems still remain. Some freezing and occasional jumping. More rare now and jumping only for a few seconds forward as opposed to minutes. No hoppity skipping.

I'm wondering if the booster might be the problem. Are some better than others? Mine is an Antiference PSF1200.

Any thoughts? We do see occasional freezes on live tv but we almost always watch recorded so it's difficult to quantify.

Is picture freezing and jumping forward a few seconds a common phenomenon these days?

Thanks..
 
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What you're thinking of as the "booster" is actually just a 12V DC power supply. It's sending power up the aerial cable to the real booster somewhere either in the loft or on the aerial mast. If it's designed to go on the mast then it's called a Masthead Amp (unsurprisingly). It doesn't mean it has to be on the TV mast though.

The same kind of power supply might be used to power a multi-way distribution amplifier located in the loft. Remote power like this is referred to as "phantom power". It's safer that leaving a 240V device unattended in the loft or trying to power something out in the elements with 240V.

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Changing the PSF1200 then will do nothing unless it's actually faulty in some way. I wouldn't rule that out, but I'd certainly investigate a bit further before pointing the finger.


Blocking, freezing, skipping can be caused by lots of signal power related issues. The basics are either too little or too much signal. The way digital works is that channels are grouped in to what's known as muxes (multiplex). For example; receiving the PSB1 BBCA mux will provide the TV with 1 BBC One (regional), 2 BBC Two England, 7 BBC Three, 9 BBC Four, 120 CBBC, 121 CBeebies, 130 BBC News, 131 BBC Parliament, 301 BBC Red Button 1, plus 13 others. If you're getting a problem with one of those channels then the others in the group will be affected the same way too. So, your first job is to find out specifically which channels are affected so you can determine which muxes are causing the problem. Once you know that then you're half way to finding out if it's a signal power issue. Here's a list of the muxes and the TV channels each carries. This is the same for any location in the UK. Where things might change is if your local transmitter is a repeater station or a Freeview Lite transmitter.

Next, the muxes are not all the same power. The PSB ones are Public Service Broadcast, so these are the ones that have to reach as many UK residents as possible. They're broadcast with the highest power and given priority on the Lite transmitters. The COM ones stand for commercial. They're run at lower powers or not at all on Lite transmitters.

By now you should have enough information to work out if there's a pattern to the signal disruption.


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Things get slightly more complicated when the aerial's reception characteristics are thrown in to the mix. The typical "wideband high gain" aerials are decent at the upper end of the frequency range but poor with the lower mux channel numbers. So it's possible to have a situation where an aerial was installed that had marginal reception with the lower power muxes. It's then moved or something else has happened to degrade the signal just beyond the threshold of what's acceptable.

If there's too much signal then that could be because of the recent channel shuffling. A strong PSB channel that was originally placed where a wideband aerial is weakest might well have been just under the upper limit. If it was moved further up the frequency range then it could have tipped over the top.

Have a look at the TV and PVR's signal meters. They aren't 100% accurate but they will help you look at trends. Signal Quality is the most important. That should be the higher value out of the two bars. Signal Strength is far less important.


None of this rules out other issues such as tree growth, new buildings, aerial being put up poorly etc etc or something as simple as a difference in the sensitivity of the tuners.
 
Just to add to Lucid's list: an increasingly common cause of your symptom is a "leaky" HDMI lead. To eliminate this possibility, disconnect any HDMI lead(s) completely. Use a Scart cable temporarily, instead. If you find that the HDMI lead is the apparent culprit, make sure that your coaxial fly-lead(s) is/are fully screened (e.g. WF100 cable) and any wall plate is screened. If that doesn't help, try a different HDMI lead. It should be as short as possible and placed well away from the aerial lead.

More possibilities here: http://www.satcure.co.uk/tech/freeview_problems.htm
 
Thanks for such a comprehensive reply Lucid. Thanks also to you Sam.

Lots to think about and info to gather.

Unfortunately the hard disk player doesn't have a scart lead, so I can't compare scart against hdmi. I'll look into the hdmi lead and socket ideas and will maybe buy another hdmi lead - any recommendations?

Cheers.
 
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Just thought I'd mention that I unscrewed the aerial faceplate today and it's not of the screened type -at least not like the ones I've seen on the internet. There's no metal box that surrounds the lead connection area. I've ordered one of those and will report back in a few weeks with progress.
 
If you want more specific suggestions, tell us your postcode, the type and location of your aerial and the exact type of coaxial cable. I assume you already clicked on the link I gave and that you read the page of information.

Oh, and if you really want to thank anyone, save words and simply click on their "Thanks" button.
 
Cheers.

Yes, I read that link thanks.

Post code is EX8 3DS. Aerial was fitted just over a year ago. Not sure how to describe the type. It has a mast head amplifier, as explained earlier by Lucid. Also, no idea what type of coax cable. I could supply photos, I suppose, of the aerial and the back of the face plate, would that help? I can post images on this site, yes?

Just been playing around with the signal info stuff on the Panasonic Hard Disk Recorder. A bit confusing really. The quality of most channels, certainly the hd ones, was always 10 out of 10 indicated by a long green bar. However, the strength bar is grey on all channels, almost suggesting that there is no strength at all. I checked all channels and although the upper quality bar sometimes became shorter and changed colour, the strength bar was always grey.

I was about to un plug the aerial to see if I could get a reaction on that strength bar but got kicked out cos it started recording something. Will try that later.

Edit: aerial is on a pole mounted near the top of our gable wall. We have pretty tall semi and the aerial is on a level with the chimney pots, curiously pointing in a slightly different direction to our neighbours (ours is rotated about 10 degrees west of his).
 
Received and fitted a screened type wall plate on Tuesday. Let's see how that goes.
 

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