That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

MM

In article , MM
writes
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

Provided you have a reasonable analogue picture in the kitchen I'd
expect an extension of at least 10m to be a walk in the park and 20m may
well be fine. If your LCD telly is digital then you may find that a
cheap fly lead (extension) will let in electrical interference resulting
in occasional picture breakup. If this is the case then a better, double
screened lead should fix it but it may have to be made up by an aerial
shop for you, asking for CT100 cable if that is the route you take.
--
fred
FIVE TV's superbright logo - not the DOG's, it's ********

On Sat, 9 Apr 2011 16:47:32 +0100, fred wrote:

In article , MM
writes
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

Provided you have a reasonable analogue picture in the kitchen I'd
expect an extension of at least 10m to be a walk in the park and 20m may
well be fine. If your LCD telly is digital then you may find that a
cheap fly lead (extension) will let in electrical interference resulting
in occasional picture breakup. If this is the case then a better, double
screened lead should fix it but it may have to be made up by an aerial
shop for you, asking for CT100 cable if that is the route you take.

Thanks, Fred. The electrical shop in the town near me has two 10m
cables, a cheap one (£4) and a better quality one for HD (£6.99). But
anyway I was too late to get there this afternoon, being a Saturday.

MM

In article , MM
scribeth thus
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

MM

Depends on what the signal level is like at the wallplate. If a decent
level already then it may well be fine over some 10's of feet if your in
a not that good area to start with then perhaps not.

Best if to try it and see amplifier less, ands if it goes noisy add an
amp but at the driving end of the cable else you'll -amplify- the losses
too;!..


Do use a decent double screened cable such as CT100 or similar..
--
Tony Sayer

In message , tony sayer
wrote

Do use a decent double screened cable such as CT100 or similar..

Background info
http://www.wrightsaerials.tv/articles/coax-cable-quality.shtml

Guide price for a decent quality cable is around 40/70p metre for short
lengths. Example
http://www.tlc-direct.co.uk/Products/CAPF100W.html



--
Alan
news2009 {at} admac {dot} myzen {dot} co {dot} uk

MM wrote:
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

MM
gets a bit crap after 50 meters of sat grade coax

On Sat, 09 Apr 2011 17:28:26 +0100, John Rumm
wrote:

On 09/04/2011 16:21, MM wrote:
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

This is alas one of those "how long is a piece of string" questions. It
depends on how much signal you have and what quality it is. How much
your TV needs. And what quality of cable you are using to extend it.

All of which are unknowns.

So without any test equipment, the best you can do is try it and see.
Assuming the picture is good now, then dropping in another 15m of decent
quality foil screened co-ax is unlikely to degrade it much. If you
wanted 50m then that will make more difference.

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

And the LCD with probably have a digital tuner, which will open another
can of worms depending on the local reception conditions for digital
channels.

If you have a few minutes to spare, there is another question:

My house is equipped with a Philex SLx6 aerial amplifier in the loft.
This has 6 output sockets, of which only five are connected at present
(kitchen, bedroom 1, bedroom 2, bedroom 3, and living room).

Reception is excellent in four rooms, but in the living room the
picture was grainy. Not too bad, but definitely not as good as in any
of the other rooms, all supplied with the same type of wall outlet.

I have just spent an hour up in the loft tracing the cables from the
amplifier to the various rooms in order to isolate the one going to
the living room and causing the grainy picture. In the process of this
tracing I pulled the cable out from under the loft insulation as I
tracked along it so that I could expose the whole cable and check for
"funnies", like someone may have hit it with a chisel or something.

Then I connected my little portable once more to the living room wall
outlet, went back up into the loft and reconnected the suspect cable
to the amplifier.... Result: Perfect reception!

But why? What gives here? (I am no electrician, although I understand
the basics.) The cable is at present simply laying across the loft, on
top of the insulation (rock wool, not that that makes any difference).

In a nutshell:
Cable routed "neatly" alongside joists under insulation = poor
reception
Cable simply laid across the loft on top - good reception

This cable is very long. From the aerial amplifier to the wall outlet
downstairs it must be 15 metres, perhaps even 17.

I was expecting to have to pull the cable out of the conduit and
possibly replace it, but that now seems superfluous, since I don't
care if the cable simply lays there where it now is.

Any comments (from anyone) most welcome.

Thanks!

MM

MM wrote:
On Sat, 09 Apr 2011 17:28:26 +0100, John Rumm
wrote:

On 09/04/2011 16:21, MM wrote:
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

This is alas one of those "how long is a piece of string" questions. It
depends on how much signal you have and what quality it is. How much
your TV needs. And what quality of cable you are using to extend it.

All of which are unknowns.

So without any test equipment, the best you can do is try it and see.
Assuming the picture is good now, then dropping in another 15m of decent
quality foil screened co-ax is unlikely to degrade it much. If you
wanted 50m then that will make more difference.

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

And the LCD with probably have a digital tuner, which will open another
can of worms depending on the local reception conditions for digital
channels.

If you have a few minutes to spare, there is another question:

My house is equipped with a Philex SLx6 aerial amplifier in the loft.
This has 6 output sockets, of which only five are connected at present
(kitchen, bedroom 1, bedroom 2, bedroom 3, and living room).

Reception is excellent in four rooms, but in the living room the
picture was grainy. Not too bad, but definitely not as good as in any
of the other rooms, all supplied with the same type of wall outlet.

I have just spent an hour up in the loft tracing the cables from the
amplifier to the various rooms in order to isolate the one going to
the living room and causing the grainy picture. In the process of this
tracing I pulled the cable out from under the loft insulation as I
tracked along it so that I could expose the whole cable and check for
"funnies", like someone may have hit it with a chisel or something.

Then I connected my little portable once more to the living room wall
outlet, went back up into the loft and reconnected the suspect cable
to the amplifier.... Result: Perfect reception!

But why? What gives here? (I am no electrician, although I understand
the basics.) The cable is at present simply laying across the loft, on
top of the insulation (rock wool, not that that makes any difference).

In a nutshell:
Cable routed "neatly" alongside joists under insulation = poor
reception
Cable simply laid across the loft on top - good reception

This cable is very long. From the aerial amplifier to the wall outlet
downstairs it must be 15 metres, perhaps even 17.

I was expecting to have to pull the cable out of the conduit and
possibly replace it, but that now seems superfluous, since I don't
care if the cable simply lays there where it now is.

Any comments (from anyone) most welcome.

Thanks!

MM

I would hazard a guess that the likeliest cause is a poor connection in the
plug that's that's going to the amp. I'd take it apart and make sure that
the screen isn't shorting with the central conductor.

Tim

On Sat, 9 Apr 2011 18:32:39 +0000 (UTC), Tim
wrote:

MM wrote:
On Sat, 09 Apr 2011 17:28:26 +0100, John Rumm
wrote:

On 09/04/2011 16:21, MM wrote:
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

This is alas one of those "how long is a piece of string" questions. It
depends on how much signal you have and what quality it is. How much
your TV needs. And what quality of cable you are using to extend it.

All of which are unknowns.

So without any test equipment, the best you can do is try it and see.
Assuming the picture is good now, then dropping in another 15m of decent
quality foil screened co-ax is unlikely to degrade it much. If you
wanted 50m then that will make more difference.

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

And the LCD with probably have a digital tuner, which will open another
can of worms depending on the local reception conditions for digital
channels.

If you have a few minutes to spare, there is another question:

My house is equipped with a Philex SLx6 aerial amplifier in the loft.
This has 6 output sockets, of which only five are connected at present
(kitchen, bedroom 1, bedroom 2, bedroom 3, and living room).

Reception is excellent in four rooms, but in the living room the
picture was grainy. Not too bad, but definitely not as good as in any
of the other rooms, all supplied with the same type of wall outlet.

I have just spent an hour up in the loft tracing the cables from the
amplifier to the various rooms in order to isolate the one going to
the living room and causing the grainy picture. In the process of this
tracing I pulled the cable out from under the loft insulation as I
tracked along it so that I could expose the whole cable and check for
"funnies", like someone may have hit it with a chisel or something.

Then I connected my little portable once more to the living room wall
outlet, went back up into the loft and reconnected the suspect cable
to the amplifier.... Result: Perfect reception!

But why? What gives here? (I am no electrician, although I understand
the basics.) The cable is at present simply laying across the loft, on
top of the insulation (rock wool, not that that makes any difference).

In a nutshell:
Cable routed "neatly" alongside joists under insulation = poor
reception
Cable simply laid across the loft on top - good reception

This cable is very long. From the aerial amplifier to the wall outlet
downstairs it must be 15 metres, perhaps even 17.

I was expecting to have to pull the cable out of the conduit and
possibly replace it, but that now seems superfluous, since I don't
care if the cable simply lays there where it now is.

Any comments (from anyone) most welcome.

Thanks!

MM

I would hazard a guess that the likeliest cause is a poor connection in the
plug that's that's going to the amp. I'd take it apart and make sure that
the screen isn't shorting with the central conductor.

I don't see how it can be that, since I haven't disturbed the
amplifier end of the cable hardly at all. There is about a metre of
loose cable where it connects to the amplifier and I had already
unpluged then re-plugged the cable into the amp, trying differing
output sockets on the amp. But all the while the cable was routed the
way it was originally (along the joists, turned a right-angle, beneath
the eaves across to the outside wall, then into the conduit),
reception was grainy; "un-routed" the cable and simply laid it flat
across the insulation, good reception!

MM

On Sat, 09 Apr 2011 20:35:42 +0100, John Rumm
wrote:

..... Of possibly you had some physical stress on
the cable (kink, crush, fold etc) that was impairing its performance,
and moving it has released that.

Well, indeed, the cable *was* kinked somewhat at the point it turned a
right-angle, then lay along (parallel to) the eaves. That is, the
cable was laid loose (resting on the plasterboard of the ceiling
beneath) until the right-angle, and at that point the installer had
secured the cable with a cable clip, then turned it through 90 deg to
go under the eaves. However, if that was an electrical cable it would
not affect anything, so is an aerial cable different (more
susceptible) in this respect? Of course, I am well pleased with my
stint in the loft this afternoon, 'cos I had visions of chasing a new
cable route down the wall, since the cable appears to be a tight as a
duck's arse inside the conduit down to the living room.

MM

On Apr 9, 5:30*pm, John Rumm wrote:
On 09/04/2011 16:49, MM wrote:



On Sat, 9 Apr 2011 16:47:32 +0100, *wrote:

In , MM
*writes
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

Provided you have a reasonable analogue picture in the kitchen I'd
expect an extension of at least 10m to be a walk in the park and 20m may
well be fine. If your LCD telly is digital then you may find that a
cheap fly lead (extension) will let in electrical interference resulting
in occasional picture breakup. If this is the case then a better, double
screened lead should fix it but it may have to be made up by an aerial
shop for you, asking for CT100 cable if that is the route you take.

Thanks, Fred. The electrical shop in the town near me has two 10m
cables, a cheap one ( 4) and a better quality one for HD ( 6.99). But
anyway I was too late to get there this afternoon, being a Saturday.

You would probably be better going to somewhere like Maplin, and getting
them to cut you a length of CT100 (or similar quality) co-ax, and
sticking a plug on either end. Many of the pre-made TV fly leads are
poor to say the least.

Use the right cable type
http://wiki.diyfaq.org.uk/index.php?...for_TV_aerials
and fit plugs. Ready made flyleads are too often hopeless. One that
claims HD compatibility only makes itself look more suspect.


NT

In message , MM
wrote
so is an aerial cable different (more
susceptible) in this respect?

Yes. Google for "aerial cable crushing". The bend radius of a coaxial
cable should be no less than 10x the diameter of the cable. The cable
should not be crushed. A foam dielectric can held prevent (not
eliminate) crushing.
--
Alan
news2009 {at} admac {dot} myzen {dot} co {dot} uk

In article ,
MM wrote:
} There is about a metre of
}loose cable where it connects to the amplifier and I had already
}unpluged then re-plugged the cable into the amp, trying differing
}output sockets on the amp. But all the while the cable was routed the
}way it was originally (along the joists, turned a right-angle, beneath
}the eaves across to the outside wall, then into the conduit),
}reception was grainy; "un-routed" the cable and simply laid it flat
}across the insulation, good reception!

I expect this is co-axial cable with a solid copper central conductor.
Probably that has broken somewhere internally and by moving it you
have put it into a position where the ends of the break are now being
pushed against each other. The most likely place for such a break is
where it was turned too sharply in a bend. It may be ok now, or
heating and cooling may make the join fail again. If so, since the
fault is obviously somewhere in the section you disturbed, you can
just replace that bit.

In message
-septemb
er.org, Tim writes

I would hazard a guess that the likeliest cause is a poor connection in the
plug that's that's going to the amp. I'd take it apart and make sure that
the screen isn't shorting with the central conductor.

Tim


Another favourite problem is pin of the plug, assuming a Belling Lee
plug rather than an F. Quite often for speed the installer will not
solder the coax inner to the pin of the plug, maybe he will have crudely
crimped it with a pair of side cutters, most likely not though. This
can lead to problems years down the line with corrosion isolating the
coax inner from the pin. Any slight movement could have remade the
connection. Although the pin and inner may not have been making contact
there could have been enough capacitance for a signal to get across, but
not strong enough to give a good picture.
--
Bill

"Bill" wrote in message
...
In message
-septemb
er.org, Tim writes

I would hazard a guess that the likeliest cause is a poor connection in
the
plug that's that's going to the amp. I'd take it apart and make sure that
the screen isn't shorting with the central conductor.

Tim


Another favourite problem is pin of the plug, assuming a Belling Lee plug
rather than an F. Quite often for speed the installer will not solder the
coax inner to the pin of the plug, maybe he will have crudely crimped it
with a pair of side cutters, most likely not though. This can lead to
problems years down the line with corrosion isolating the coax inner from
the pin. Any slight movement could have remade the connection. Although
the pin and inner may not have been making contact there could have been
enough capacitance for a signal to get across, but not strong enough to
give a good picture.

I never solder those things, and I expect the tiniest amount of capacitance
will do the job. Actually, I often only have to hold the plug near the RF
socket on a TV, and I start to get a picture, on an analogue set at least.

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can jump
an air gap of a tenth of an inch, and from one point to another, while an
unsoldered wire will have a 1 or 2cm length in a hollow tube so a greater
capacitive effect)

--
Bartc

In message , BartC wrote

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can jump
an air gap of a tenth of an inch,

But if the coax is also being used to supply power to an amplifier
(unlikely in the case of the OP) the dc voltage will not jump the 2 or
3mm gap.

--
Alan
news2009 {at} admac {dot} myzen {dot} co {dot} uk

On Sat, 9 Apr 2011 20:54:50 +0000 (UTC), Charles Bryant
wrote:

In article ,
MM wrote:
} There is about a metre of
}loose cable where it connects to the amplifier and I had already
}unpluged then re-plugged the cable into the amp, trying differing
}output sockets on the amp. But all the while the cable was routed the
}way it was originally (along the joists, turned a right-angle, beneath
}the eaves across to the outside wall, then into the conduit),
}reception was grainy; "un-routed" the cable and simply laid it flat
}across the insulation, good reception!

I expect this is co-axial cable with a solid copper central conductor.
Probably that has broken somewhere internally and by moving it you
have put it into a position where the ends of the break are now being
pushed against each other. The most likely place for such a break is
where it was turned too sharply in a bend. It may be ok now, or
heating and cooling may make the join fail again. If so, since the
fault is obviously somewhere in the section you disturbed, you can
just replace that bit.

Ah, good to know, thanks!

MM

On Sat, 09 Apr 2011 23:36:27 +0100, John Rumm
wrote:

On 09/04/2011 20:55, MM wrote:
On Sat, 09 Apr 2011 20:35:42 +0100, John Rumm
wrote:

..... Of possibly you had some physical stress on
the cable (kink, crush, fold etc) that was impairing its performance,
and moving it has released that.

Well, indeed, the cable *was* kinked somewhat at the point it turned a
right-angle, then lay along (parallel to) the eaves. That is, the
cable was laid loose (resting on the plasterboard of the ceiling
beneath) until the right-angle, and at that point the installer had
secured the cable with a cable clip, then turned it through 90 deg to
go under the eaves. However, if that was an electrical cable it would
not affect anything, so is an aerial cable different (more
susceptible) in this respect? Of course, I am well pleased with my

Very much so. With power, as long as the two wires are kept apart and
insulated from each other and the surroundings, then a cable will carry
on doing its job. With radio (i.e. TV) frequency signals the behaviour
of cables gets significantly more complex, and the design and geometry
of the cable has a big effect on how well it carries the (massively more
delicate than mains power) signal. Deform the spacing between the centre
conductor and the screen of the co-ax and it can significantly alter the
amount it attenuates the signal passing through it.

stint in the loft this afternoon, 'cos I had visions of chasing a new
cable route down the wall, since the cable appears to be a tight as a
duck's arse inside the conduit down to the living room.

Well it sounds like you have escaped that for the mo, although with the
switch to digital you may not be out of the woods yet ;-)

Thanks for the above and previously. What might I have to do when the
new telly arrives next week? It's a Samsung LCD with Freeview (not
Freeview HD).

By the way, I already have a Freeview USB stick connected to the PC.
This is connected to exactly the same wall plate that feeds the
analogue TV, if I had one in the computer room. The Freeview reception
is excellent and I can receive a large number of TV and radio
channels. This little gizmos has been absolutely fantastic and cost
about 20 quid from Amazon about two years ago.

So, the aerial + amplifier appears fine for receiving Freeview
already.

MM

On Sat, 09 Apr 2011 23:48:30 +0100, BartC wrote:

I never solder those things, and I expect the tiniest amount of
capacitance will do the job.

Not true. Apart from the attenuation caused, you're completely ignoring
the importance of matching the characteristic impedance of the cable to
its load. Adding a 'tiny capacitance' in series will wreck this matching,
resulting in reflections. These may be visible as ghosting/ringing (on an
analogue signal) or cause deep notches in the frequency response
(affecting both analogue and digital reception).

Actually, I often only have to hold the plug near the RF
socket on a TV, and I start to get a picture, on an analogue set at
least.

That may well be true, but it doesn't alter the importance of correct
matching.

Richard.
http://www.rtrussell.co.uk/

In message , BartC writes
"Bill" wrote in message
...




Another favourite problem is pin of the plug, assuming a Belling Lee plug
rather than an F. Quite often for speed the installer will not solder the
coax inner to the pin of the plug, maybe he will have crudely crimped it
with a pair of side cutters, most likely not though. This can lead to
problems years down the line with corrosion isolating the coax inner from
the pin. Any slight movement could have remade the connection. Although
the pin and inner may not have been making contact there could have been
enough capacitance for a signal to get across, but not strong enough to
give a good picture.

I never solder those things, and I expect the tiniest amount of capacitance
will do the job. Actually, I often only have to hold the plug near the RF
socket on a TV, and I start to get a picture, on an analogue set at least.

You're just asking for trouble!

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can jump
an air gap of a tenth of an inch, and from one point to another, while
an unsoldered wire will have a 1 or 2cm length in a hollow tube so a
greater capacitive effect)

I feel quite sick!

If you can't (or can't be bothered to) solder the coax solid inner
conductor into the pin, instead of 'crimping' it with a pair of side
cutters or pliers, I reckon it's better first to put a slight 'kink' the
inner conductor at about 5mm from the end. The kink should be made
sufficient to make it quite difficult to push the conductor into the
pin. Not only does it give you a reliable, relatively permanent contact,
but it has the additional advantage that the plug can later be removed,
and re-used!
--
Ian

On Sun, 10 Apr 2011 03:06:51 +0100, Alan
wrote:

In message , BartC wrote

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can jump
an air gap of a tenth of an inch,

But if the coax is also being used to supply power to an amplifier
(unlikely in the case of the OP) the dc voltage will not jump the 2 or
3mm gap.

The amplifier is plugged into the mains. They fitted a 13A socket in
the loft near the amp just for that purpose.

I've now seen that the FULL output socket on the amp is supposed to
have a terminator if nothing is connected to it. According to the user
guide I downloaded, the installer is supposed to fit this. He didn't.

Can one get a terminator from Wilkinson, or do I have to order one
online?

(Dunno what the effect is of not having the terminator present.)

MM

On Sat, 09 Apr 2011 23:36:27 +0100, John Rumm
wrote:

Well it sounds like you have escaped that for the mo, although with the
switch to digital you may not be out of the woods yet ;-)

Nope!

Everything you and others said about a suspected dodgy connection or
broken wire must be true, since this morning I moved the cable some
small distance (still left it lying on top of the insulation, i.e. not
routed along the joists) and now the picture is back to being grainy.

I moved the TV to another room in case the signal this morning (from
the transmitter) is weaker, but no, reception in the kitchen is as
good as ever (i.e. excellent).

I've been up and down the step-ladder numerous times, with the TV in
the hall on an extension cable from the wall plate, and up in the loft
I've jiggled like crazy, but the picture doesn't improve. Dunno
whether it helps the diagnosis, but when I say grainy, don't get the
idea that the picture is unwatchable. It is still watchable, but it is
NOT as clear and as sharp as in any of the other rooms.

But last night it WAS excellent, even in the living room, so it must
have been pure fluke the way I first un-routed the cable and left it
lying.

Dunno what to try now. I checked the plug where it goes into the amp
and it looks all right. Same with the wall plate, I've got it off the
wall and it's dangling there, but the connection seems well-made.

MM

MM wrote:

Dunno what to try now. I checked the plug where it goes into the amp
and it looks all right. Same with the wall plate, I've got it off the
wall and it's dangling there, but the connection seems well-made.

Typical of either damaged cable or a bad connection. Disassemble the
plug and wall plate and re-make the connections properly, and if that
doesn't cure it, you *could* get a proper aerial cable tester and find
out where the cable fault is, or you could just replace and re-run the
cable properly.

If it's the polythene and air insulated type, once the insulation gets
kinked, it can cause problems later. Foam insulated isn't so bad, but
damage can still linger. Foil shield is, IME, more fragile, too, and can
be a right pig to terminate correctly.

--
Tciao for Now!

John.

In message , MM
writes
I've now seen that the FULL output socket on the amp is supposed to
have a terminator if nothing is connected to it. According to the user
guide I downloaded, the installer is supposed to fit this. He didn't.

Can one get a terminator from Wilkinson, or do I have to order one
online?

(Dunno what the effect is of not having the terminator present.)

Only if you want to be a perfectionist, you will be OK without it. I
have put anylisers on the output of distribution amps and looked at the
levels with and without having the main, and unused, outputs terminated,
there is a measurable difference but not enough to cause the problem you
described.



--
Bill

Bill wrote:
In message , MM
writes
I've now seen that the FULL output socket on the amp is supposed to
have a terminator if nothing is connected to it. According to the user
guide I downloaded, the installer is supposed to fit this. He didn't.

Can one get a terminator from Wilkinson, or do I have to order one
online?

(Dunno what the effect is of not having the terminator present.)

Only if you want to be a perfectionist, you will be OK without it. I
have put anylisers on the output of distribution amps and looked at the
levels with and without having the main, and unused, outputs terminated,
there is a measurable difference but not enough to cause the problem you
described.




depends on how buffered it is: can cause cable resonances if its all
been done with attenuative pads.

But if it DID briefly work WITHOUT the pad, that aint the problem....

In message , BartC writes

I never solder those things, and I expect the tiniest amount of capacitance
will do the job. Actually, I often only have to hold the plug near the RF
socket on a TV, and I start to get a picture, on an analogue set at least.

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can jump
an air gap of a tenth of an inch, and from one point to another, while
an unsoldered wire will have a 1 or 2cm length in a hollow tube so a
greater capacitive effect)


A description of how to fit them is he-

http://www.megalithia.com/elect/bellinglee/index.html

If a job is worth doing then it is worth doing properly!! :-)


--
Bill

In article , MM
scribeth thus
On Sat, 09 Apr 2011 17:28:26 +0100, John Rumm
wrote:

On 09/04/2011 16:21, MM wrote:
That is, the cable from the back of the TV to the wall plate.

I need to watch the TV in the annexe which has no wall plate, so I
could run an extension from, say, the kitchen's wall plate. But what
is the limit to the length and would I need some sort of booster?

This is alas one of those "how long is a piece of string" questions. It
depends on how much signal you have and what quality it is. How much
your TV needs. And what quality of cable you are using to extend it.

All of which are unknowns.

So without any test equipment, the best you can do is try it and see.
Assuming the picture is good now, then dropping in another 15m of decent
quality foil screened co-ax is unlikely to degrade it much. If you
wanted 50m then that will make more difference.

The aerial is currently driving a 14"analogue (CRT) Sony portable, but
will soon be connected to an LCD TV.

And the LCD with probably have a digital tuner, which will open another
can of worms depending on the local reception conditions for digital
channels.

If you have a few minutes to spare, there is another question:

My house is equipped with a Philex SLx6 aerial amplifier in the loft.
This has 6 output sockets, of which only five are connected at present
(kitchen, bedroom 1, bedroom 2, bedroom 3, and living room).

Reception is excellent in four rooms, but in the living room the
picture was grainy. Not too bad, but definitely not as good as in any
of the other rooms, all supplied with the same type of wall outlet.

I have just spent an hour up in the loft tracing the cables from the
amplifier to the various rooms in order to isolate the one going to
the living room and causing the grainy picture. In the process of this
tracing I pulled the cable out from under the loft insulation as I
tracked along it so that I could expose the whole cable and check for
"funnies", like someone may have hit it with a chisel or something.

Then I connected my little portable once more to the living room wall
outlet, went back up into the loft and reconnected the suspect cable
to the amplifier.... Result: Perfect reception!

But why? What gives here? (I am no electrician, although I understand
the basics.) The cable is at present simply laying across the loft, on
top of the insulation (rock wool, not that that makes any difference).

In a nutshell:
Cable routed "neatly" alongside joists under insulation = poor
reception
Cable simply laid across the loft on top - good reception

This cable is very long. From the aerial amplifier to the wall outlet
downstairs it must be 15 metres, perhaps even 17.

I was expecting to have to pull the cable out of the conduit and
possibly replace it, but that now seems superfluous, since I don't
care if the cable simply lays there where it now is.

Any comments (from anyone) most welcome.

Thanks!

MM

Was the plug soldered properly?. Was the cable kinked at all anywhere?..
--
Tony Sayer

In article , BartC scribeth
thus


"Bill" wrote in message
...
In message
-septemb
er.org, Tim writes

I would hazard a guess that the likeliest cause is a poor connection in
the
plug that's that's going to the amp. I'd take it apart and make sure that
the screen isn't shorting with the central conductor.

Tim


Another favourite problem is pin of the plug, assuming a Belling Lee plug
rather than an F. Quite often for speed the installer will not solder the
coax inner to the pin of the plug, maybe he will have crudely crimped it
with a pair of side cutters, most likely not though. This can lead to
problems years down the line with corrosion isolating the coax inner from
the pin. Any slight movement could have remade the connection. Although
the pin and inner may not have been making contact there could have been
enough capacitance for a signal to get across, but not strong enough to
give a good picture.

I never solder those things, and I expect the tiniest amount of capacitance
will do the job. Actually, I often only have to hold the plug near the RF
socket on a TV, and I start to get a picture, on an analogue set at least.

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can jump
an air gap of a tenth of an inch, and from one point to another, while an
unsoldered wire will have a 1 or 2cm length in a hollow tube so a greater
capacitive effect)


Sorry but thats not very good practice or science come to that. If in
the RF I work in we had unsoldered joints there would be fires and
smoke;!..
--
Tony Sayer

In message on Sun, 10 Apr 2011
12:30:10 +0100
MM wrote:


I've now seen that the FULL output socket on the amp is supposed to
have a terminator if nothing is connected to it. According to the user
guide I downloaded, the installer is supposed to fit this. He didn't.

Can one get a terminator from Wilkinson, or do I have to order one
online?


Unlikely!

A terminator is just a 75 ohm resistor. 'F' type terminators are available but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or go to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Fit the resistor inside the plug between the centre pin and the body. If you
have a soldering iron, it is easiest to solder the wire onto the cable clamp -
as well as the centre pin, of course - but otherwise you will have to devise
your own method of trappimg it between the clamp and the body. This will vary
slightly from one plug manufacturer to another.

This will NOT fix your current problem, though - but it might fix other
problems with you DTV reception that you aren't even aware of at the moment!

--

Terry

In article ,
Terry Casey scribeth thus
In message on Sun, 10 Apr 2011
12:30:10 +0100
MM wrote:


I've now seen that the FULL output socket on the amp is supposed to
have a terminator if nothing is connected to it. According to the user
guide I downloaded, the installer is supposed to fit this. He didn't.

Can one get a terminator from Wilkinson, or do I have to order one
online?


Unlikely!

Yeah!, Wilkinson's do couplers...


A terminator is just a 75 ohm resistor. 'F' type terminators are available but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or go to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Fit the resistor inside the plug between the centre pin and the body. If you
have a soldering iron, it is easiest to solder the wire onto the cable clamp -
as well as the centre pin, of course - but otherwise you will have to devise
your own method of trappimg it between the clamp and the body. This will vary
slightly from one plug manufacturer to another.

This will NOT fix your current problem, though - but it might fix other
problems with you DTV reception that you aren't even aware of at the moment!


--
Tony Sayer

In message , tony sayer
writes


Sorry but thats not very good practice or science come to that. If in
the RF I work in we had unsoldered joints there would be fires and
smoke;!..


Hi Tony,
A few years back I stripped out a rack that had contained Band 3 bases.
One of the N to N leads I re-used was O/C when I took a plug apart the
pin had never been soldered. There were a number of black arc burns on
the inner copper. I often wondered how many faults they had had
reported that they never found!
--
Bill

In message ,
Terry Casey wrote
but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or go to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Or fit a F type 75 ohm termination to a F to a Belling Lee converter
http://www.admac.myzen.co.uk/F_coax/
A few quid for the lot from Ebay.

--
Alan
news2009 {at} admac {dot} myzen {dot} co {dot} uk

"tony sayer" wrote in message
...
In article , BartC scribeth

I never solder those things, and I expect the tiniest amount of
capacitance
will do the job. Actually, I often only have to hold the plug near the RF
socket on a TV, and I start to get a picture, on an analogue set at least.

(In fact, I'm just done a test on a digital TV, disconnecting the RF lead
at
a joint: if the outer screen is in contact, I start to get a picture when
the inner core is 2 or 3 mm away from the centre pin! So the signal can
jump
an air gap of a tenth of an inch, and from one point to another, while an
unsoldered wire will have a 1 or 2cm length in a hollow tube so a greater
capacitive effect)


Sorry but thats not very good practice or science come to that. If in
the RF I work in we had unsoldered joints there would be fires and
smoke;!..

The signal from a TV aerial is at microscopic power levels. And I do tend to
bend the inner core of the coax to make sure it makes contact inside the
hollow pin of the plug.

But if it doesn't, doesn't it just form a tiny capacitor? (And I wouldn't be
surprised if the first thing the signal encountered inside the TV was an
actual 10pf or 100pf series capacitor.)

--
Bartc

In message , Alan
writes
In message ,
Terry Casey wrote
but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or go to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Or fit a F type 75 ohm termination to a F to a Belling Lee converter
http://www.admac.myzen.co.uk/F_coax/
A few quid for the lot from Ebay.

If you're not 'into' electronics, that's by far the easiest way to do
it.

I've been in the electronics industry since the 1960s and, surprisingly,
I've never come across any commercial Belling Lee 75 ohm terminations.
In contrast, F terminations are everywhere. [I presume that that is
because they are used on professional equipment in the cable TV
industry.] I've always had to make my own B&Ls, or do as suggested
above.
--
Ian

BartC wrote:
"tony sayer" wrote in message
...
In article , BartC scribeth

I never solder those things, and I expect the tiniest amount of
capacitance
will do the job. Actually, I often only have to hold the plug near
the RF
socket on a TV, and I start to get a picture, on an analogue set at
least.

(In fact, I'm just done a test on a digital TV, disconnecting the RF
lead at
a joint: if the outer screen is in contact, I start to get a picture
when
the inner core is 2 or 3 mm away from the centre pin! So the signal
can jump
an air gap of a tenth of an inch, and from one point to another,
while an
unsoldered wire will have a 1 or 2cm length in a hollow tube so a
greater
capacitive effect)


Sorry but thats not very good practice or science come to that. If in
the RF I work in we had unsoldered joints there would be fires and
smoke;!..

The signal from a TV aerial is at microscopic power levels. And I do
tend to bend the inner core of the coax to make sure it makes contact
inside the hollow pin of the plug.

But if it doesn't, doesn't it just form a tiny capacitor? (And I
wouldn't be surprised if the first thing the signal encountered inside
the TV was an actual 10pf or 100pf series capacitor.)

10pf is a fair bit more than a wire inside a hollow pin.

And the FIRST thing is generally a 75ohm load, actually.

If the cable is separated from that, you can get nasty cable resonances.
Especially on LONG cables........

Ian Jackson wrote:
In message , Alan
writes
In message ,
Terry Casey wrote
but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or go
to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire
connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Or fit a F type 75 ohm termination to a F to a Belling Lee converter
http://www.admac.myzen.co.uk/F_coax/
A few quid for the lot from Ebay.

If you're not 'into' electronics, that's by far the easiest way to do it.

I've been in the electronics industry since the 1960s and, surprisingly,
I've never come across any commercial Belling Lee 75 ohm terminations.

How odd. I bought several from the shop that supplied my dis amp.

In contrast, F terminations are everywhere. [I presume that that is
because they are used on professional equipment in the cable TV
industry.] I've always had to make my own B&Ls, or do as suggested above.

In message on Sun, 10 Apr 2011 14:37:03 +0100
tony sayer wrote:

In article ,
Terry Casey scribeth thus
In message on Sun, 10 Apr 2011
12:30:10 +0100
MM wrote:

Can one get a terminator from Wilkinson,


Unlikely!

Yeah!, Wilkinson's do couplers...


That is hardly a terminator - and, unless they do the uncommon male-male
coupler, it won't even fit!

What do you suggest he puts on the other end of the coupler, anyway ...?

--

Terry

In message on Sun, 10 Apr 2011 16:06:39 +
0100
Ian Jackson wrote:

In message , Alan
writes
In message ,
Terry Casey wrote
but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or go to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Or fit a F type 75 ohm termination to a F to a Belling Lee converter
http://www.admac.myzen.co.uk/F_coax/
A few quid for the lot from Ebay.

If you're not 'into' electronics, that's by far the easiest way to do
it.

I've been in the electronics industry since the 1960s and, surprisingly,
I've never come across any commercial Belling Lee 75 ohm terminations.

Teleste used IEC (belling) connectors on their CATV kit and I'm sure they also
provided a 75 ohm termination ...

In contrast, F terminations are everywhere. [I presume that that is
because they are used on professional equipment in the cable TV
industry.] I've always had to make my own B&Ls, or do as suggested
above.

A resistor and Belling plug would be much cheaper though!

--

Terry

In message ,
Terry Casey writes
In message on Sun, 10 Apr 2011 16:06:39 +
0100
Ian Jackson wrote:

In message , Alan
writes
In message ,
Terry Casey wrote
but,
if your amp uses 'Belling' style connectors (like an ordinary aerial
plug/socket on a TV, find a local shop that sells components - or
to Maplin
- and buy a 75 ohm resistor (the old fashioned kind with wire
connections) and
a plug. (If you can't get a 75 ohm resistor, 82 ohms is acceptable.)

Or fit a F type 75 ohm termination to a F to a Belling Lee converter
http://www.admac.myzen.co.uk/F_coax/
A few quid for the lot from Ebay.

If you're not 'into' electronics, that's by far the easiest way to do
it.

I've been in the electronics industry since the 1960s and, surprisingly,
I've never come across any commercial Belling Lee 75 ohm terminations.

Teleste used IEC (belling) connectors on their CATV kit and I'm sure they also
provided a 75 ohm termination ...

In contrast, F terminations are everywhere. [I presume that that is
because they are used on professional equipment in the cable TV
industry.] I've always had to make my own B&Ls, or do as suggested
above.

A resistor and Belling plug would be much cheaper though!

I did have a bit 'contact' with the Teleste headend equipment. I
remember the short purpose-made jumpers, but I don't recall finding any
IEC/B&L terminations being used with it. While I'd be surprised if
Teleste didn't supply them (for use where required), I've never seen
them offered in any vendors' catalogues etc (although 'The Natural
Philosopher' has).
--
Ian

In message , The Natural Philosopher
writes
Ian Jackson wrote:



If you're not 'into' electronics, that's by far the easiest way to do it.
I've been in the electronics industry since the 1960s and,
surprisingly, I've never come across any commercial Belling Lee 75 ohm
terminations.

How odd. I bought several from the shop that supplied my dis amp.

Terry Street says that Teleste did them (from what he suggests, at
'professional' prices!), but I'm sure I have never personally seen any -
anywhere.
--
Ian