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Default Strange Happenings on Retuning a Digi Box

Grateful for any advice on my situation with a Digi Box, when i've just done
a *factory-default* on a Humax HDR Fox T2, which I did because i was missing
some TV channels.

I'm located in Finchley North London near a Relay Station, but my main
transmitter is Crystal Palace.

When i did my factory default the BBC TV programs were rubbish (picture
breaking up). I remembered some advice to use a 'splitter' to reduce the
signal strength for some reason when doing the re-tune.

After re-tuning using the splitter the BBC stations as well as all the other
stations seem to work OK. But I now get some HD stations in the channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks


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Default Strange Happenings on Retuning a Digi Box

r brooks wrote:

After re-tuning using the splitter the BBC stations as well as all the other
stations seem to work OK. But I now get some HD stations in the channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.


If the channels in the 800s are duplicates of the ones in the 100s,
ignore them. They won't eat anything.

Bill
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Default Strange Happenings on Retuning a Digi Box

Well Crystal Palace does seem to lose channels when I do a retune. I've
found that doing a factory retune with no aerial, even though the box was
reset first makes this better.
I think though that your main issue is that you are getting two transmitters
and the box is throwing them in as it finds them. If you are lucky they end
up with the weaker ones up on the high channels but this does not always
happen as I discovered here during a tropo lift last autumn.
I guess an attenuator is not really what you want unless you know for sure
that the signals from the relay are lower, which I'm guessing they are not
even though they may be cross polarised.
Does the box in question allow you to see the channels the multiplexes are
on that you have in your main channels and if they are not the ones you
want there, then you need some way to re order them. Trouble is after any
retune things tend to get scrambled again.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"r brooks" wrote in message
...
Grateful for any advice on my situation with a Digi Box, when i've just
done a *factory-default* on a Humax HDR Fox T2, which I did because i was
missing some TV channels.

I'm located in Finchley North London near a Relay Station, but my main
transmitter is Crystal Palace.

When i did my factory default the BBC TV programs were rubbish (picture
breaking up). I remembered some advice to use a 'splitter' to reduce the
signal strength for some reason when doing the re-tune.

After re-tuning using the splitter the BBC stations as well as all the
other stations seem to work OK. But I now get some HD stations in the
channels numbered in the 800s' as well as the 100s. The HD channels in
the 100s work ok, but all the HD channels in the 800s are still breaking
up.

Grateful for any advice on what I might usefully do further. Thanks



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Default Strange Happenings on Retuning a Digi Box

On 10/01/2014 22:04, r brooks wrote:
[...]
After re-tuning using the splitter the BBC stations as well as all the other
stations seem to work OK. But I now get some HD stations in the channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks


Try a manual retune - page 53 in the user guide and
http://www.digitaluk.co.uk/coveragec...anual_retuning

--
Andy
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Default Strange Happenings on Retuning a Digi Box

In message , Andy Wade
writes
On 10/01/2014 22:04, r brooks wrote:
[...]
After re-tuning using the splitter the BBC stations as well as all the other
stations seem to work OK. But I now get some HD stations in the channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks


Try a manual retune - page 53 in the user guide and
http://www.digitaluk.co.uk/coveragec...anual_retuning

Unfortunately, not all set-top boxes give you the option of doing a
manual tune (or maybe the facility is hidden somewhere in the menus).

If you have to do an automatic tune, rather than use a splitter, a 20db
variable attenuator will give you better control of the signal level. I
was in B&Q yesterday, and I saw they do one (£7?) - which, if you need
one quickly, might be more convenient than getting one elsewhere online.
--
Ian


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Default Strange Happenings on Retuning a Digi Box


"Ian Jackson" wrote in message
news
In message , Andy Wade
writes
On 10/01/2014 22:04, r brooks wrote:
[...]
After re-tuning using the splitter the BBC stations as well as all the
other
stations seem to work OK. But I now get some HD stations in the
channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks


Try a manual retune - page 53 in the user guide and
http://www.digitaluk.co.uk/coveragec...anual_retuning

Unfortunately, not all set-top boxes give you the option of doing a manual
tune (or maybe the facility is hidden somewhere in the menus).

If you have to do an automatic tune, rather than use a splitter, a 20db
variable attenuator will give you better control of the signal level. I
was in B&Q yesterday, and I saw they do one (£7?) - which, if you need one
quickly, might be more convenient than getting one elsewhere online.
--
Ian


----------------------------------------------------------------------------------------
Ian thanks. Two questions: What function does the use of a splitter serve,
I understand it weakens the incoming signal but what is the purpose of that
please?

If I get a variable attenuator from b and q, what kind of adjustment would I
want to be making with it? Thanks.


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Default Strange Happenings on Retuning a Digi Box

In message , r brooks
writes

"Ian Jackson" wrote in message
news
In message , Andy Wade
writes
On 10/01/2014 22:04, r brooks wrote:
[...]
After re-tuning using the splitter the BBC stations as well as all the
other
stations seem to work OK. But I now get some HD stations in the
channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks

Try a manual retune - page 53 in the user guide and
http://www.digitaluk.co.uk/coveragec...anual_retuning

Unfortunately, not all set-top boxes give you the option of doing a manual
tune (or maybe the facility is hidden somewhere in the menus).

If you have to do an automatic tune, rather than use a splitter, a 20db
variable attenuator will give you better control of the signal level. I
was in B&Q yesterday, and I saw they do one (£7?) - which, if you need one
quickly, might be more convenient than getting one elsewhere online.
--
Ian


------------------------------------------------------------------------
----------------
Ian thanks. Two questions: What function does the use of a splitter serve,
I understand it weakens the incoming signal but what is the purpose of that
please?

If I get a variable attenuator from b and q, what kind of adjustment would I
want to be making with it? Thanks.

I mistakenly thought I saw someone advised inserting a splitter in the
aerial feed (to lower the signal level) - but looking back, it must have
been in another thread!

However, sometimes inserting a splitter in the aerial feed is suggested
(as these are readily available). This will lower the TV signal level by
4 dB (6 for the cheap resistive ones) - and this might just may be
sufficient to make the set-top box, when it's doing the automatic
channel scan, ignore the unwanted, weaker signals and detect only the
stronger wanted channels. Obviously, with a splitter (or any other fixed
attenuator), you don't have much control over how much signal loss you
put in (other than use more than one of them).

The variable attenuator (as suggested by Paul), enables you to control
how far you reduce the signal. A variable 20dB attenuator will enable
you to reduce the signal by a maximum of 20dB (1/10th of the original),
so with a bit of trial and error, you should be able to persuade the
set-top box to 'see' only the strongest channels, and ignore the rest.
Once you've done the scan, you should remove the attenuator, and only
use it again if you need to do another scan.

An obvious problem with the above is if the unwanted signals are
stronger than the wanted ones. This might be the case if you want to
receive the full complement of TV channels from the main transmitter,
but a stronger local relay transmitter is offering a reduced number of
channels (as many do).

As you see, it's all a bit of a fiddle. It's a lot easier if your
set-top box or TV set does allow you to do a manual tune. To do this,
you'll need to enter (in turn) the individual transmission channel
numbers. For Crystal Palace (standard definition) they are 22, 23, 25,
26, 28 and 29, with 33 and 37 for high definition (see link):
http://www.ukfree.tv/txdetail.php?a=TQ339712&PGSTART=0

--
Ian
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Default Strange Happenings on Retuning a Digi Box

Ian Jackson wrote:

An obvious problem with the above is if the unwanted signals are
stronger than the wanted ones. This might be the case if you want to
receive the full complement of TV channels from the main transmitter,
but a stronger local relay transmitter is offering a reduced number of
channels (as many do).


Much depends on the receiver. Does is simply chose by signal strength or
does it chose by signal quality?

Bill
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Default Strange Happenings on Retuning a Digi Box

r brooks wrote:

Ian thanks. Two questions: What function does the use of a splitter serve,
I understand it weakens the incoming signal but what is the purpose of that
please?


The idea is to weaken the signals so that the weaker set (from the
'wrong' transmitter) are too weak to be stored. Meanwhile the stronger
ones remain strong enough to be stored.


If I get a variable attenuator from b and q, what kind of adjustment would I
want to be making with it? Thanks.


Trial and error until you achieve the above. Start at the max atten end.

Bill
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Default Strange Happenings on Retuning a Digi Box

Ian Jackson wrote:

If you have to do an automatic tune, rather than use a splitter, a 20db
variable attenuator will give you better control of the signal level. I
was in B&Q yesterday, and I saw they do one (£7?) - which, if you need
one quickly, might be more convenient than getting one elsewhere online.


Or the free option, a loosely coupled pair of faraday loops (if that's
the proper name for them).

Bill


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Default Strange Happenings on Retuning a Digi Box

In article , Bill Wright
scribeth thus
Ian Jackson wrote:

If you have to do an automatic tune, rather than use a splitter, a 20db
variable attenuator will give you better control of the signal level. I
was in B&Q yesterday, and I saw they do one (£7?) - which, if you need
one quickly, might be more convenient than getting one elsewhere online.


Or the free option, a loosely coupled pair of faraday loops (if that's
the proper name for them).

Bill


Well hats a nice idea..

And cheap too!....

--
Tony Sayer

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tony sayer wrote:

Or the free option, a loosely coupled pair of faraday loops (if that's
the proper name for them).

Bill


Well hats a nice idea..

And cheap too!....


When I was rigging for DER they wouldn't pay for attenuators, and the
sets of the time needed one when in Ponty and Barnsley. So I made loops.
My old German mentor showed me the trick, when I was a kid. Did I ever
mention Hans? He was in the Hitler Youth as a lad, and then in 1945 him
and his family lived in a sewer for months. He came to the UK on holiday
in the late 40s and stayed. A good immigrant.

Bill
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Default Strange Happenings on Retuning a Digi Box

On Saturday, 11 January 2014 11:14:32 UTC, Ian Jackson wrote:

Try a manual retune - page 53 in the user guide and
http://www.digitaluk.co.uk/coveragec...anual_retuning


Unfortunately, not all set-top boxes give you the option of doing a
manual tune (or maybe the facility is hidden somewhere in the menus).


I suspect this one does given it's on page 53 of the user guide! ;-)
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Default Strange Happenings on Retuning a Digi Box

On 10/01/2014 22:04, r brooks wrote:
Grateful for any advice on my situation with a Digi Box, when i've just done
a *factory-default* on a Humax HDR Fox T2, which I did because i was missing
some TV channels.

I'm located in Finchley North London near a Relay Station, but my main
transmitter is Crystal Palace.

When i did my factory default the BBC TV programs were rubbish (picture
breaking up). I remembered some advice to use a 'splitter' to reduce the
signal strength for some reason when doing the re-tune.

After re-tuning using the splitter the BBC stations as well as all the other
stations seem to work OK. But I now get some HD stations in the channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks


Your aerial is picking up signals from two different transmitters.

When this happens Humax non YouView boxes replicate channels by placing
them in the location you have cited.

There is a solution but one way is to have your aerial realigned.

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Default Strange Happenings on Retuning a Digi Box

In article ,
says...

On 10/01/2014 22:04, r brooks wrote:
Grateful for any advice on my situation with a Digi Box, when i've just done
a *factory-default* on a Humax HDR Fox T2, which I did because i was missing
some TV channels.

I'm located in Finchley North London near a Relay Station, but my main
transmitter is Crystal Palace.

When i did my factory default the BBC TV programs were rubbish (picture
breaking up). I remembered some advice to use a 'splitter' to reduce the
signal strength for some reason when doing the re-tune.

After re-tuning using the splitter the BBC stations as well as all the other
stations seem to work OK. But I now get some HD stations in the channels
numbered in the 800s' as well as the 100s. The HD channels in the 100s
work ok, but all the HD channels in the 800s are still breaking up.

Grateful for any advice on what I might usefully do further. Thanks


Your aerial is picking up signals from two different transmitters.

When this happens Humax non YouView boxes replicate channels by placing
them in the location you have cited.

There is a solution but one way is to have your aerial realigned.


The answer is simple - decide which transmitter you want to use and then
go to this website to identify the channel numbers used by that
transmitter. Write them down and keep the piece of paper safe for next
time.

http://www.digitaluk.co.uk/

Enter your postcode, house number and make sure you tick the box next to
the detailed view option.

Now, reset all the channels and do an individual manual tune for each of
the channel numbers identified.

If you can receive channels from more than one transmitter (my aerial
can see four of the possible six) it is the only reliable way and given
it is painless and easy to do, there is no reason not to.


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Default Strange Happenings on Retuning a Digi Box

Gareth Davies wrote:

There is a solution but one way is to have your aerial realigned.


Because of the extreme sensitivity of many modern DTT receivers this is
unlikely to help, unless the aerial was grossly wrong in the first place.

Bill
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Default Strange Happenings on Retuning a Digi Box


"Bill Wright" wrote in message
...
Gareth Davies wrote:

There is a solution but one way is to have your aerial realigned.


Because of the extreme sensitivity of many modern DTT receivers this is
unlikely to help, unless the aerial was grossly wrong in the first place.

Bill


-----------------------------------------------------------------------------------------

Conclusion:

Bought a variable attenuator on line for £3.15 inc postage. screwed it out
for maximum resistance (less one complete turn out of five turns) and it
eliminated all channels in the 800 range on the factory default/automatic
retune.

Many thanks to all for helping me get good results.


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Default Strange Happenings on Retuning a Digi Box

In message , r brooks
writes

"Bill Wright" wrote in message
...
Gareth Davies wrote:

There is a solution but one way is to have your aerial realigned.


Because of the extreme sensitivity of many modern DTT receivers this is
unlikely to help, unless the aerial was grossly wrong in the first place.

Bill


------------------------------------------------------------------------
-----------------

Conclusion:

Bought a variable attenuator on line for £3.15 inc postage. screwed it out
for maximum resistance (less one complete turn out of five turns) and it
eliminated all channels in the 800 range on the factory default/automatic
retune.

Many thanks to all for helping me get good results.

Good conclusion. You can take it out until you do another scan.
--
Ian
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Default Strange Happenings on Retuning a Digi Box

Ian Jackson wrote:
In message , r brooks
writes

"Bill Wright" wrote in message
...
Gareth Davies wrote:

There is a solution but one way is to have your aerial realigned.


Because of the extreme sensitivity of many modern DTT receivers this is
unlikely to help, unless the aerial was grossly wrong in the first
place.

Bill


------------------------------------------------------------------------
-----------------

Conclusion:

Bought a variable attenuator on line for £3.15 inc postage. screwed it
out
for maximum resistance (less one complete turn out of five turns) and it
eliminated all channels in the 800 range on the factory default/automatic
retune.

Many thanks to all for helping me get good results.

Good conclusion. You can take it out until you do another scan.


I usually leave it in as long as long as the wanted channels are plenty
strong enough. People forget to use it when they do a retune, and it
could help with 4G (etc) problems.

Bill
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Default Strange Happenings on Retuning a Digi Box

r brooks wrote:
"Bill Wright" wrote in message
...
Gareth Davies wrote:

There is a solution but one way is to have your aerial realigned.

Because of the extreme sensitivity of many modern DTT receivers this is
unlikely to help, unless the aerial was grossly wrong in the first place.

Bill


-----------------------------------------------------------------------------------------

Conclusion:

Bought a variable attenuator on line for £3.15 inc postage. screwed it out
for maximum resistance (less one complete turn out of five turns) and it
eliminated all channels in the 800 range on the factory default/automatic
retune.

Many thanks to all for helping me get good results.


For maximum reliability of the wanted signals try again with less
attenuation, and again and again, until the unwanted signals reappear,
then go back a step or two.

Bill


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