Odd problem this and I wonder if anyone can shed some light on it.

My new Philips freeview digibox makes a noise just like someone has not
turned a tap off properly i.e a 'dripping' or 'chirruping' sound comes from
the freeview channels. If I switch to the normal TV it goes away. Very
irritating esp. after paying £120 for a new aerial.

Has anyone ever heard of a such a phenomenon??

TIA

Jb

Jb wrote:
Odd problem this and I wonder if anyone can shed some light on it.

My new Philips freeview digibox makes a noise just like someone has not
turned a tap off properly i.e a 'dripping' or 'chirruping' sound comes from
the freeview channels. If I switch to the normal TV it goes away. Very
irritating esp. after paying £120 for a new aerial.

Has anyone ever heard of a such a phenomenon??


Yep. Its faulty. Return it.

Probably got a dry jointed capacitor that slipped past final QA.

TIA

Jb

Jb wrote:
Odd problem this and I wonder if anyone can shed some light on it.

My new Philips freeview digibox makes a noise just like someone has
not turned a tap off properly i.e a 'dripping' or 'chirruping' sound
comes from the freeview channels. If I switch to the normal TV it
goes away. Very irritating esp. after paying £120 for a new aerial.

Has anyone ever heard of a such a phenomenon??

It is a common effect caused by low signal level or interference on a
digital signal. You could ask in uk.tech.digital-tv for more advice
particularly from the resident experts expert Bill Wright.

Peter Crosland

"Peter Crosland" wrote in message
...
Jb wrote:
Odd problem this and I wonder if anyone can shed some light on it.

My new Philips freeview digibox makes a noise just like someone has
not turned a tap off properly i.e a 'dripping' or 'chirruping' sound
comes from the freeview channels. If I switch to the normal TV it
goes away. Very irritating esp. after paying £120 for a new aerial.

Has anyone ever heard of a such a phenomenon??

It is a common effect caused by low signal level or interference on a
digital signal. You could ask in uk.tech.digital-tv for more advice
particularly from the resident experts expert Bill Wright.

Peter Crosland

Thanks 'll go and ask Bill

Jb

Jb was thinking very hard :
Odd problem this and I wonder if anyone can shed some light on it.

My new Philips freeview digibox makes a noise just like someone has not
turned a tap off properly i.e a 'dripping' or 'chirruping' sound comes from
the freeview channels. If I switch to the normal TV it goes away. Very
irritating esp. after paying £120 for a new aerial.

If it is a fairly regular noise, take it back to the supplier as it is
probably faulty. Much less regular, then that could be interference
causing the signal drop out, or simply poor reception - check the
signal level/quality.

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

In uk.d-i-y, Jb wrote:
My new Philips freeview digibox makes a noise just like someone has not
turned a tap off properly i.e a 'dripping' or 'chirruping' sound comes from
the freeview channels. If I switch to the normal TV it goes away. Very
irritating esp. after paying £120 for a new aerial.

Has anyone ever heard of a such a phenomenon??

That sounds to me like the noise that digital receivers make if the
signal is weak or subject to interference. Such popping noises are the
digital equivalent of hiss and distortion in analogue receivers. If the
box has a signal strength display that's where I'd look first.

--
Mike Barnes

"Mike Barnes" wrote in message
...
In uk.d-i-y, Jb wrote:
My new Philips freeview digibox makes a noise just like someone has not
turned a tap off properly i.e a 'dripping' or 'chirruping' sound comes
from
the freeview channels. If I switch to the normal TV it goes away. Very
irritating esp. after paying £120 for a new aerial.

Has anyone ever heard of a such a phenomenon??

That sounds to me like the noise that digital receivers make if the
signal is weak or subject to interference. Such popping noises are the
digital equivalent of hiss and distortion in analogue receivers. If the
box has a signal strength display that's where I'd look first.

--
Mike Barnes

No signal strength meter and the noise is more of a 'plop plop' not a
clicking, nor is it regular

In article ,
Jb wrote:
No signal strength meter and the noise is more of a 'plop plop' not a
clicking, nor is it regular

It does sound like digital drop out. If the aerial is daisy chained
through the box to the TV and it is a correct one and the analogue picture
good I'd say the box is faulty.

I've got a Philips box that does show signal strength, though.

--
*I am a nobody, and nobody is perfect; therefore I am perfect*

Dave Plowman London SW
To e-mail, change noise into sound.

Jb wrote:

Has anyone ever heard of a such a phenomenon??

this is either radio frequency interference, poor signal from the aerial
or interference coming from the mains. the latter should be eliminated
by the unit's power supply, but in some cases this is not enough if your
wiring is dodgy or you have bad load on the same mains. from what you
are describing, it does not relate to switching inductive load on/off so
the latter doesn't apply to you.

the sounds that you hear are results of erroneous decoding of the audio
frames. if you watch close enough, you will see blocking and other
artefacts in the picture as well (see last paragraph).

signal strength is not the only parameter when it comes to digital
reception. error rate (BER) is not less important. DVB protocols can
cope with some amount of errors, then glitches start to appear. check
whether the aerial was installed and directed correctly, whether the
cable/connectors are suitable. is it just one run of cable? some aerials
are more sensitive to direction. maybe the installers checked for
picture but did not care to direct properly. some aerials are plain
unsuitable for DVB-T. I personally came across an aerial that worked
fine for lower UHF channels but produced bad BERs for higher ones, which
resulted in BBC channels showing up ok and SkyNews erroring all the
time. with aerials made recently and certified this is unlikely.

all this has to be checked, unless, of course your freeview box is just
faulty. try replacing it with a friend's and see if the problem
persists. some boxes are more sensitive to bad signal.

/max

"maxim naumov" wrote in message
...
Jb wrote:

Has anyone ever heard of a such a phenomenon??

this is either radio frequency interference, poor signal from the aerial
or interference coming from the mains. the latter should be eliminated by
the unit's power supply, but in some cases this is not enough if your
wiring is dodgy or you have bad load on the same mains. from what you are
describing, it does not relate to switching inductive load on/off so the
latter doesn't apply to you.

the sounds that you hear are results of erroneous decoding of the audio
frames. if you watch close enough, you will see blocking and other
artefacts in the picture as well (see last paragraph).

signal strength is not the only parameter when it comes to digital
reception. error rate (BER) is not less important. DVB protocols can cope
with some amount of errors, then glitches start to appear. check whether
the aerial was installed and directed correctly, whether the
cable/connectors are suitable. is it just one run of cable? some aerials
are more sensitive to direction. maybe the installers checked for picture
but did not care to direct properly. some aerials are plain unsuitable for
DVB-T. I personally came across an aerial that worked fine for lower UHF
channels but produced bad BERs for higher ones, which resulted in BBC
channels showing up ok and SkyNews erroring all the time. with aerials
made recently and certified this is unlikely.

all this has to be checked, unless, of course your freeview box is just
faulty. try replacing it with a friend's and see if the problem persists.
some boxes are more sensitive to bad signal.

/max

Thanks for that. I'll try moving the booster from the lounge to the loft and
get it as close to the aerial as possible (as advised by others). We can
rule out any and all mains borne interference including voltage step change,
harmonic distortion and flicker. Power quality is my area of work so I know
my supply is good. Someone suggested trying a different box so that's
another option. Are the £20 variety as good as the £50 ones or do you get
what you pay for?

Jb

Jb wrote:

Thanks for that. I'll try moving the booster from the lounge to the loft and

you did not mention the signal booster. this could be the source of your
problems. why do you need one? boosters often introduce too much noise
noise, which could be fatal for digital reception. it is especially
difficult to deal with them when there is no gain regulator. have you
tried removing it altogether? I'd say that if, with the new high-gain
aerial properly installed you still need a booster, then you're probably
stuck without DVB. it is unlikely that in this case a signal booster can
solve the problem. I'd advise to check the aerial installation, possibly
move it around and lifting it higher. in BBC website you can find the
coordinates of your nearest transmitter.

also, check whether the booster is suitable for digital reception.

if you or your friends have a laptop/PC with a DVB-T card, try it. these
are more sensitive to poor signal and the software has signal power meter.

my supply is good. Someone suggested trying a different box so that's
another option. Are the £20 variety as good as the £50 ones or do you get
what you pay for?

I had a good-quality on-digital philips box, a nokia box, then was
thinking of buying a branded box and then got a 20-quid cheapo from a
friend, called technika (AFAIK, tesco brand). out of three I had, the
cheapo is the best when it comes to reception. the hardware is the same
in almost all cheapos. I'd advise buying one in metal housing though.
the prismatic one is different hardware but was positively reviewed.

I also have three PC tuners working 24/7. here you can't save much and
should always buy a proven brand and good model.

/max

"maxim naumov" wrote in message
...
Jb wrote:

Thanks for that. I'll try moving the booster from the lounge to the loft
and

you did not mention the signal booster. this could be the source of your
problems. why do you need one? boosters often introduce too much noise
noise, which could be fatal for digital reception. it is especially
difficult to deal with them when there is no gain regulator. have you
tried removing it altogether? I'd say that if, with the new high-gain
aerial properly installed you still need a booster, then you're probably
stuck without DVB. it is unlikely that in this case a signal booster can
solve the problem. I'd advise to check the aerial installation, possibly
move it around and lifting it higher. in BBC website you can find the
coordinates of your nearest transmitter.

also, check whether the booster is suitable for digital reception.

if you or your friends have a laptop/PC with a DVB-T card, try it. these
are more sensitive to poor signal and the software has signal power meter.

my supply is good. Someone suggested trying a different box so that's
another option. Are the £20 variety as good as the £50 ones or do you get
what you pay for?

I had a good-quality on-digital philips box, a nokia box, then was
thinking of buying a branded box and then got a 20-quid cheapo from a
friend, called technika (AFAIK, tesco brand). out of three I had, the
cheapo is the best when it comes to reception. the hardware is the same in
almost all cheapos. I'd advise buying one in metal housing though. the
prismatic one is different hardware but was positively reviewed.

I also have three PC tuners working 24/7. here you can't save much and
should always buy a proven brand and good model.

/max

Just to take this discussion a bit further - would you recommend buying a
new TV with a built in digital tuner - or is it likely to fail? Is it better
'insurance' to have a separate set-top box?
I would like to buy a TV with a built in one, but on reflection I have
replaced my STB twice.

On Thu, 21 Jun 2007 08:52:00 GMT, "John"
mused:


Just to take this discussion a bit further - would you recommend buying a
new TV with a built in digital tuner - or is it likely to fail? Is it better
'insurance' to have a separate set-top box?
I would like to buy a TV with a built in one, but on reflection I have
replaced my STB twice.

You'd be doing well to find a TV without tuner, and most tuners now
are digital so for the price then it'd be cheaper to use a TV with
built in digital tuner and then buy a cheap external box in the future
if the one in the TV ends up being unrepairable.

One day, a TV with digital tuner will be the norm, like a TV with
analogue tuner is now. Set top boxes will start to become rarer. I
would imagine this will be in about 2020ish.
--
Regards,
Stuart.

In article ,
Jb wrote:
Someone suggested trying a different box so that's another option. Are
the £20 variety as good as the £50 ones or do you get what you pay for?

I've only tried one cheap one and it was rubbish. I returned it and
swopped it for a better one. It also lacked the outputs I needed.
I've got 5 assorted Freeview boxes here. The best performing (never any
freezing etc) are my Topfield PVR and Sony STB. The others all have some
issues or other - the worse being a Sagem I got for free with my TV.

--
*Virtual reality is its own reward*

Dave Plowman London SW
To e-mail, change noise into sound.

In message , "Dave Plowman (News)"
writes
In article ,
Jb wrote:
Someone suggested trying a different box so that's another option. Are
the £20 variety as good as the £50 ones or do you get what you pay for?

I've only tried one cheap one and it was rubbish. I returned it and
swopped it for a better one. It also lacked the outputs I needed.
I've got 5 assorted Freeview boxes here. The best performing (never any
freezing etc) are my Topfield PVR and Sony STB. The others all have some
issues or other - the worse being a Sagem I got for free with my TV.

Yeah, I've had to replace several Sagem boxes

Funnily enough, the best one seems to be the first (Hitachi) one I
bought years ago


--
geoff

Jb wrote:
"maxim naumov" wrote in message
...
Jb wrote:

Has anyone ever heard of a such a phenomenon??
this is either radio frequency interference, poor signal from the aerial
or interference coming from the mains. the latter should be eliminated by
the unit's power supply, but in some cases this is not enough if your
wiring is dodgy or you have bad load on the same mains. from what you are
describing, it does not relate to switching inductive load on/off so the
latter doesn't apply to you.

the sounds that you hear are results of erroneous decoding of the audio
frames. if you watch close enough, you will see blocking and other
artefacts in the picture as well (see last paragraph).

signal strength is not the only parameter when it comes to digital
reception. error rate (BER) is not less important. DVB protocols can cope
with some amount of errors, then glitches start to appear. check whether
the aerial was installed and directed correctly, whether the
cable/connectors are suitable. is it just one run of cable? some aerials
are more sensitive to direction. maybe the installers checked for picture
but did not care to direct properly. some aerials are plain unsuitable for
DVB-T. I personally came across an aerial that worked fine for lower UHF
channels but produced bad BERs for higher ones, which resulted in BBC
channels showing up ok and SkyNews erroring all the time. with aerials
made recently and certified this is unlikely.

all this has to be checked, unless, of course your freeview box is just
faulty. try replacing it with a friend's and see if the problem persists.
some boxes are more sensitive to bad signal.

/max

Thanks for that. I'll try moving the booster from the lounge to the loft and
get it as close to the aerial as possible (as advised by others). We can
rule out any and all mains borne interference including voltage step change,
harmonic distortion and flicker. Power quality is my area of work so I know
my supply is good. Someone suggested trying a different box so that's
another option. Are the £20 variety as good as the £50 ones or do you get
what you pay for?

Jb


I dunno. I have all sony boxes and none of the display this sort of
issue under poor signal. The audio is either there, or it break's up
completely. If it does, the picture goes also, and you look at the
analogue as an alternative, 90% of the time its of execrable quality due
to multipath..I happen to be on the far side of several continental
transmitters that are the other side of my local xmitter..in direct line
of site.

Thats why I think the box is faulty.

The sound SOUNDS more like a nasty sort of LF instability in the power
supply..

The Natural Philosopher wrote:

issue under poor signal. The audio is either there, or it break's up
completely. If it does, the picture goes also

this is nature of DVB broadcasting. sound, video, subtitles, telext --
all go on the same frequency using the same modulation. this applies to
a group of channels. another group will use a different
frequency/modulation type. that's why BBC1 reception is usually more
reliable and of better quality than, say, Sky Sports. if there are
unrecoverable errors in the stream, both audio and video will suffer. if
only sound is glitching and picture is ok, then most likely the signal
is ok and the unit is faulty.

regarding separate/built-in receivers: it is unlikely that the built-in
tuner will fail sooner than the TV itself. even if it does, you can
still use an external one. just check in advance that you like the user
interface. some of them are appalling, be that a built-in receiver or an
external one.

/max

On Jun 21, 11:47 pm, maxim naumov wrote:
The Natural Philosopher wrote:
issue under poor signal. The audio is either there, or it break's up
completely. If it does, the picture goes also

FWIW, this is deliberate (I was involved in designing some of the
early OnDigital STBs). If the audio signal is corrupt, then it will be
muted. This is because if you were to hear the audio equivalent of the
sort of macroblock patterns you sometimes see with low signal stength
etc., it would drive you mad!

It's kinda interesting that people seem to be able to cope with major
distortion on vision more than sound. I guess one reason is that you
can just turn your head away from the visuals, whereas the sound is
more pervasive. One of the nice things about simple modulation
schemes is that they tend to degrade more gracefully...

jon N