Random loss of TV signal

[kikoy]

I had a similar problem with a recent TV and in the end it was the coaxial cable that caused random losses. Sony seem to be more sensitive to small drops in quality than other brands. If I were you, I would test another direct cable from the splitter to make sure that it doesn't come from this specific section.

Mini Militia App Lock​

 

[monday]

Thanks for this. It’s also my suspicion that these current Sony sets are more sensitive to signal quality or external interference. This is compounded by, as I have mentioned earlier in this thread, that another, older, Sony digital set is entirely unaffected. I tried to get some information about the differences between the old and new sets out of Sony’s service engineers but just got told “they are totally different”. Helpful!

I’d be interested to know the nature of the interruptions you got? Mine are blanking of sound and vision for maybe 2-3s, always followed by a second one 20s later. Always the same but occurring randomly, sometimes only once an evening, sometimes several times, sometimes not at all. This double blanking makes think something is switching on, then off, but I haven’t tracked it down yet.

The first aerial company I called changed the pre-made coax lead from the wall socket to the TV. This restored signal strength and quality to 90+/100 and he pronounced it fixed but the same evening it was exactly as before. (He did say that low quality of this flying lead is the most common problem they get and they always change it before going any further). More recently I have run a new coax from the splitter to the wall socket (no joints) - this brought signal quality and strength up to 100/100 but made no difference to the interference.The only cable not changed so far is from the roof aerial to the splitter; I think that might have to be next, with a new aerial array.

 

[Harry Bloomfield]

Thanks for that. I follow the logic but as you suggest, might be rather expensive! Probably similar cost to getting a tech out to fix it, with a new aerial if necessary. But see next reply.

As a compromise on that cost, how about an alternative test....

Buy yourself a roll of or a length of CT100 (or what ever the modern equivalent is), a plug and inline socket. Connect one end, direct to the antenna down lead (no splitter, no amps), the other straight to the back of your TV. It needn't be installed, just draped down by whatever route is easiest. Then test your reception for faults.

 

[JBR]

We do occasionally find a programme on ITV disappears half-way through. We have to go back and find the programme and re-load it.
Quite apart from this problem, I'm afraid that ITV is no longer the best channel on television as it used to be.

 

[Harry Bloomfield]

Quite apart from this problem, I'm afraid that ITV is no longer the best channel on television as it used to be.

Likewise, the BBC. Other, lesser channels are much worse, with some going off for several minutes, until someone notices, and puts a shilling in the meter It's all down to cost, and having staffing.

 

[JBR]

Likewise, the BBC. Other, lesser channels are much worse, with some going off for several minutes, until someone notices, and puts a shilling in the meter It's all down to cost, and having staffing.

I agree. I don't like the BBC, but the wife does so she pays for the licence!

 

[monday]

As a compromise on that cost, how about an alternative test....

Buy yourself a roll of or a length of CT100 (or what ever the modern equivalent is), a plug and inline socket. Connect one end, direct to the antenna down lead (no splitter, no amps), the other straight to the back of your TV. It needn't be installed, just draped down by whatever route is easiest. Then test your reception for faults.

In effect, this is what I have already done, except it is from the splitter output to the TV wall socket. This is a single length of coax, no joints. I will try connecting this direct to the aerial output lead, bypassing the splitter, and see what happens.

 

[jj4091]

I don't profess to be an expert and don't fully understand all the replies and suggestions that have been made but have you thought of getting a cheap indoor ariel and plugging it directly into your TV thereby rulng out your chimney ariel.

 

[Harry Bloomfield]

In effect, this is what I have already done, except it is from the splitter output to the TV wall socket. This is a single length of coax, no joints.

I was suggesting bypassing that, as you have no idea of its condition, so it may have suffered some damage along its length.

 

[monday]

I don't profess to be an expert and don't fully understand all the replies and suggestions that have been made but have you thought of getting a cheap indoor ariel and plugging it directly into your TV thereby rulng out your chimney ariel.

Yes I had, but the point is that the aerial/splitter/cable system works perfectly 99% of the time for the new TV and 100% of the time for my 4 other TV’s, one of which is also Sony digital but older. Something is interrupting or interfering with the signal and affects only this one TV set. Switching it to an indoor aerial is a bit of a cop out.

 

[monday]

I was suggesting bypassing that, as you have no idea of its condition, so it may have suffered some damage along its length.

But I do know it’s condition as I only put it in recently, 10m of brand new coax from TLC. The loss/interference is exactly the same as the original 20 year old cable which had two male/female plug joints in it. The only bit of original cable is from the roof aerial to the splitter input and this might be what I replace next. Bypassing the splitter by connecting that aerial lead to my new coax will cut off all other TVs in the house for a couple of days while I check results - not popular but it will have to be done. It’s not uncommon to go for an evening with no interruption only to start up again the next day to great disappointment.

 

[Harry Bloomfield]

But I do know it’s condition as I only put it in recently, 10m of brand new coax from TLC.

What was the specification of the cable you bought? Coax quality can vary enormously, especially in the outer screen, and it's ability to reject noise. Your new TV, might simply be more susceptible to noise from interference.

 

[monday]

What was the specification of the cable you bought? Coax quality can vary enormously, especially in the outer screen, and it's ability to reject noise. Your new TV, might simply be more susceptible to noise from interference.

Good point. I believe it is RG5 (copper coated steel core/'foam' insulation/aluminium foil & braided copper screen) but TLC don't provide a spec for this product.
Regarding noise interference, yes I think this is the problem, See post #40 above. Question is, what? I have eliminated thermostats, pumps, outside light sensors, fridges etc. Street lights are too far away and anyway once on, they are on for the evening.

 

[Harry Bloomfield]

Good point. I believe it is RG5 (copper coated steel core/'foam' insulation/aluminium foil & braided copper screen) but TLC don't provide a spec for this product.

That's 50 Ohm, data cable. For TV you need 75 Ohm. So that will not be helping..

 

[monday]

That's 50 Ohm, data cable. For TV you need 75 Ohm. So that will not be helping..

Apologies, RG6. I appreciate WF100 would better but have only recently found out there are so many grades of coax cable. This is quite a journey!