1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Freeview Reception Problem - Aerial Lead The Cause!

Discussion in 'Freeview' started by Jango, May 8, 2006.

  1. Jango

    Jango Guest

    Ratings:
    +0
    I have HTPC with a built in freeview card which has good freeview reception. The aerial lead from the wall socket to the freeview card was a bit tatty, a home made job out of satellite coax and a couple of 49p plugs, so I thought I'd replace it.

    So I bought a cheapo from ebay, £3 all in. With this new lead, the lower strength channels are very choppy and don't work properly.

    I'm just really surprised that a 3m cable could cause such as problem. The cheapo cable is reasonably thick and looks like fairly good quality - but obviously not.

    Maybe it isn't shielded like the coax? Has anybody heard of this sort of thing before? And has anybody any recommendations for a reasonably decent aerial lead?
  2. sbowler

    sbowler Member

    Joined:
    Mar 24, 2005
    Messages:
    3,775
    Trophy Points:
    136
    Ratings:
    +517
    Try a look at the Maplins site, they have a very good selection of coax, go for midpriced.
    • Thanks Thanks x 1
  3. SamRadford

    SamRadford Member

    Joined:
    Jul 12, 2005
    Messages:
    3,965
    Trophy Points:
    103
    Ratings:
    +366
    I've had this soooo may times when I ran a TV repair shop. I'd go to a customer's house to re-install their repaired TV set and they'd say: "Great, lovely picture", and I'd see a grainy mess. So I'd quickly make up a new wall-to-TV lead with satellite cable and plugs, connect it and watch their faces as they looked at the best TV picture they'd had for years.

    The problem's even worse with digital TV because bad leads can dump some channels completely. I no longer trust any pre-made leads. You don't know what's in them without cutting them up. So I make my own.

    There's one pre-made lead that seemed reasonably OK when I tried it and that was this...
    let me find the page...

    "CO02D - double-shielded RF lead £3.00" here:
    http://www.satcure.com/accs/page7.htm#rfleads

    It's not gold-plated or fancy in any way but if you can't make your own lead (I recommend you try) then it might be OK.
    • Thanks Thanks x 1
  4. Jango

    Jango Guest

    Ratings:
    +0
    By the sounds of it I think I'll stick with the sat coax. Might buy some bling gold plated coax plugs to tart it up a bit though! :thumbsup:
  5. Scuttlerx

    Scuttlerx Member

    Joined:
    Feb 15, 2006
    Messages:
    336
    Trophy Points:
    18
    Ratings:
    +14
    I think this may be the cause of my probs. I have lost a couple of multiplexes recently, they were ones that were occasionally a bit temperemental but now have gone completely, and along with the tv the fly lead is the only item that has been changed, I never thought it could make that much of a difference.

    Wheres a good place to get some good quality cable and connectors, somewhere online would be ok but big shop would be preferable so I can get some tomorrow! Satellite lead the best bet?
  6. SamRadford

    SamRadford Member

    Joined:
    Jul 12, 2005
    Messages:
    3,965
    Trophy Points:
    103
    Ratings:
    +366
    Assume you've got some by now but, yes, "satellite" cable is required. It needs to be "double-screened". Aluminium foil shield is probably OK indoors but use copper foil shielded outdoors. Most large hardware stores sell one version or another. If you want to know more, read Bill's excellent review: http://www.your-book.co.uk/cable.htm
  7. Nick_UK

    Nick_UK New Member

    Joined:
    Nov 13, 2004
    Messages:
    9,748
    Trophy Points:
    0
    Ratings:
    +315
    For the last couple of metres between the wall socket and the back of the PC, it's not vital to use double-screened cable. Ordinary co-ax will work just as well, but you might pick up a tiny amount more interference.
  8. Scuttlerx

    Scuttlerx Member

    Joined:
    Feb 15, 2006
    Messages:
    336
    Trophy Points:
    18
    Ratings:
    +14
    CHeers chaps, I found some satellite cable (I think, had the copper wire strands + aluminium foil) and tried that but to no avail unfortunately, think it may be an aerial problem. Only thing I can think is ive moved into a new estate and in the last few weeks houses and block of apartments opposite have started to have people move in...many a bit of interferance is being caused. Time to get the aerial out of the loft and on the roof I think :)

    Wanted to at the time but the aerial installer said for the difference it would make it would not be worth it as it would cost more. Got most channels then so I agreed but think it may be time to change
  9. SamRadford

    SamRadford Member

    Joined:
    Jul 12, 2005
    Messages:
    3,965
    Trophy Points:
    103
    Ratings:
    +366
    For the last couple of metres between the wall socket and the back of the PC, it's absolutely vital to use double-screened cable. The reason is that PCs are notoriously "noisy" - they chuck out unbelievable amounts of interference, as do monitors and TV sets.

    For the same reason, the wall socket should be shielded or avoided altogether.

    Don't believe me? OK, grab your portable AM/FM radio, tune it off-channel then bring it into the same room as your PC/monitor/TV set. What you hear is just a tiny sample (one narrow frequency range) of the interference. Try tuning it across the band.
  10. Nick_UK

    Nick_UK New Member

    Joined:
    Nov 13, 2004
    Messages:
    9,748
    Trophy Points:
    0
    Ratings:
    +315
    Sam, please don't lecture me on aerials and downleads - I've been a radio amateur for the last 24 years, so I do know a little about it. If a 2 metre length of co-axial cable picks up enough interference to spoil reception, then the aerial is not picking up enough signal anyway. I think you are forgetting that double screened co-ax has only been in standard domestic use since digital terrestrial came along, with its very low power transmitters.
  11. Ultratech

    Ultratech Member

    Joined:
    May 9, 2006
    Messages:
    51
    Trophy Points:
    8
    Ratings:
    +1
    :hiya: After moving into my present house 3yrs ago I could not believe the poor tv picture. After digging I found that EVERY connector was poorly wired. The Aerial cable goes into the attic where there is a joint, this cable run goes through the wall to the living room and a socket, then a cable run goes to the TV.
    I rewired all sockets and plugs gaining a fair bit, I replaced the living room run but could not see any gain.
    After just buying an LCD TV it is now showing more faults than the old CRT, so recently changed the Aerial to Wideband which is a fair improvement and soldered the connector cores, I have not yet changed the cable run from Aerial to attic but will as soon as the Wind and rain stop.
    I wanted to change the cable run in the wall from attic to living room but it will not budge, being enclosed what is the chance of interference here?, is it worth laying a new run outside the house? (not really keen to)
  12. SamRadford

    SamRadford Member

    Joined:
    Jul 12, 2005
    Messages:
    3,965
    Trophy Points:
    103
    Ratings:
    +366
    I think you are forgetting that Plasma screens, LCD screens and indeed PCs have only been in standard domestic use for the last few years. They spew out unbelievable amounts of "noise", which is why it's imperative to use double-screened cable, shielded connections and keep everything well away from these sources of interference. This applies especially to "magic eye" remote extenders which can be badly affected by such interference.

    Sam

    (A professional engineer - not an amateur). ;)
  13. The Nightfly

    The Nightfly Member

    Joined:
    Aug 31, 2002
    Messages:
    801
    Trophy Points:
    31
    Ratings:
    +25
    Very timely discussion. I'd popped out to Maplins this lunchtime to get 15m of TV downlead coax to run from my TV distribution amp in the loft to a new Freeview box I'm installing in the cinema room. Looked at the normal TV coax, looked at the double screened satellite coax and thought what the hell, I'll only be installing it once so went for the expensive option. After reading this I'm glad I did now.

    Allan
  14. Nick_UK

    Nick_UK New Member

    Joined:
    Nov 13, 2004
    Messages:
    9,748
    Trophy Points:
    0
    Ratings:
    +315
    At least "amateurs" know which end of a soldering iron to hold, because we haven't learned it all from text books. And by the way, where's your proof of the "unbelievable amounts of "noise" ", and why don't these products fail the EU directive (89/336/EC) if they do this ?

    Sam, I may well be a radio amateur, but I also worked as an engineer in the broadcasting industry for 15 years, before moving on to medical electronics for another 20+, so please don't be so patronising.
  15. Satmaster

    Satmaster Guest

    Ratings:
    +0
    Nick, unfortunately I must agree with Sam on this one. I install over 15 new aerials every week, and the amount of noise I can remove along with a measured rise in S/N and C/N when I always replace the cheap coax interconnects is not a figment of my imagination. The facts are as more and more electronic equipment sits around the TV the possible sources of noise have increased incredibly over the last decade.
  16. Nick_UK

    Nick_UK New Member

    Joined:
    Nov 13, 2004
    Messages:
    9,748
    Trophy Points:
    0
    Ratings:
    +315
    Are you talking about the whole cable, or just the last couple of metres ?
  17. Satmaster

    Satmaster Guest

    Ratings:
    +0
    The last couple of metres, along with the rf loop through cables. In some cases it makes no difference at all, but that will always be the case, but in most cases it does make a significant difference. Id have to agree with you on the point of normal coax, I assume you are referring to coax that is not double screened but is of the airspaced with braid variety, were I am referring to the cheap and nasty thin white leads that everyone seems to have behind the telly. The normal coax over that small distance doesnt make a lot of difference.
  18. Nick_UK

    Nick_UK New Member

    Joined:
    Nov 13, 2004
    Messages:
    9,748
    Trophy Points:
    0
    Ratings:
    +315
    Well, it's all down to signal-to-noise, isn't it ? If 2 metres of poorly screened co-ax is picking up more stray signals than the aerial itself, then the aerial can't be picking up much of a signal ? Lots of people rely on aerial amplifiers to try to compensate for poor aerials and downleads, and they don't realise that they are making the problem worse, not better.

    Don't get me wrong - Sam is a qualified engineer, and obviously knows his stuff, but I doubt that he has had a lot of real practical experience. I get very annoyed when people roll out stuff parrot fashion on these forums.....

    "Component is better than RGB"
    "A connector in the downlead will lose you half your signal"
    "Don't use wall sockets and fly-leads, they give an inferior picture"

    ........... etc, etc

    Now, whilst all these have a basis in fact, none of them are set in stone. In the past I have seen people who have wanted to do things like terminating their sat-tv cables in wall boxes, and have been talked out of doing it by people who rattle off the same "parrot fashion facts". The real truth is that if your LNB is OK, and you have an average length cable run, wall boxes and fly leads make no difference at all. I know this, because I'm doing this with both my Sky+ boxes.

    I think what I'm trying to say is "Will the people who keep telling us it can't be done please stop getting in the way of those of us who are doing it !" :D
  19. peteTV

    peteTV Member

    Joined:
    Mar 22, 2007
    Messages:
    18
    Trophy Points:
    1
    Ratings:
    +0
    I just switched the last metre of my tv lead ( that i was having interference with) with a metre extension of shielded cable lead that I had lying around- I can now run my pc without interference, and get perfect picture on freeview. :thumbsup:
  20. grahamlthompson

    grahamlthompson Well-Known Member

    Joined:
    Aug 3, 2006
    Messages:
    18,381
    Trophy Points:
    163
    Ratings:
    +3,070
  21. STOWITBELOW

    STOWITBELOW Member

    Joined:
    Nov 17, 2002
    Messages:
    1,553
    Trophy Points:
    48
    Ratings:
    +48
    When changing the fly lead (unknown origin) to one made up from shielded coax, I went from ~3 channels breaking up to the full compliment. Further changes to a complicated 'chained' recorder / tv leads to better quality Gold plated plugs & a masthead amp means I get all channels on all sets A1. The fly leads definately make a big difference & goodness knows what quality they are if they've been supplied with a tv or video.

Share This Page