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Identifying 1 from 3 Coax cables

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Dave Liquorice

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Apr 26, 2012, 5:06:55 AM4/26/12
to
Moved the DSAT only TV/PVR yesterday. Three coax's from the dish to
the kit. All three worked before the move, one now doesn't. B-(

There is a joint (F-type plugs and a coupler) in each coax outside
that had been kept dry and ventilated in plastic bag open at the
bottom. On inspection there was no sign of damp/corrsion etc in the
joins. These joints are now exposed but wrapped in self amalgamting
tape to keep the weather out.

How can I identify which is the cable that isn't working at the
joins, without removing the SAT wrapping?

It is not really practical to chase out from the bundle the duff
cable back to the joints. I've tried a "tone thrower" as one would
use on telephone/network cabling but that doesn't get 15' from the
end of the cable.

--
Cheers
Dave.



Fredxx

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Apr 26, 2012, 5:49:54 AM4/26/12
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I can't think of any other way than investing in investing in more self
amalgamating tape and split the joints.

Unless there's any way you could start from the dish side and follow the
cable to the join?

Moonraker

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Apr 26, 2012, 5:52:30 AM4/26/12
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On 26/04/2012 10:06, Dave Liquorice wrote:
If you have, or access to a sat finder you could use that. I would
gladly lend mine, however I believe you are too far away to make it
practical.

--
Residing on low ground in North Staffordshire

Mentalguy2k8

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Apr 26, 2012, 6:31:55 AM4/26/12
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"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
Have you tried each cable in each socket on the PVR to make sure it's not
one of the inputs (or dish outputs) that's blown? In my (limited)
experience, it's usually a problem local to wherever you've disconnected and
moved things, I've never had a cable just give up when left alone.

I'd disconnect all the cables at both ends, then connect just one to the
first dish output to the first PVR input, check for picture/reception. If it
works, move it along the PVR inputs 2& 3 and check again. If all is well,
unplug that cable both ends and connect the 2nd cable to output 2 of the
dish and try all 3 PVR inputs again, repeat for third input/output.

Definitely worth marking each cable as you go; if it's the only cable
connected both ends and you have a picture, you can confidently mark *both
ends* of it with "1" or "A" or whatever, then at least you'll be able to
match them up in future.

Paul D Smith

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Apr 26, 2012, 7:40:15 AM4/26/12
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"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
Can you knock up a couple of sockets, one connected to a battery, the other
to a bulb/LED and try and power the bulb/LED via the cable? Assuming it's
straight coax I imagine it would work, except for the dead cable.

Paul DS.

RobertL

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Apr 26, 2012, 7:57:53 AM4/26/12
to Dave Liquorice
On Thursday, April 26, 2012 10:06:55 AM UTC+1, Dave Liquorice wrote:
> Moved the DSAT only TV/PVR yesterday. Three coax's from the dish to
> the kit. All three worked before the move, one now doesn't. B-(
>
> There is a joint (F-type plugs and a coupler) in each coax outside
> that had been kept dry and ventilated in plastic bag open at the
> bottom. On inspection there was no sign of damp/corrsion etc in the
> joins. These joints are now exposed but wrapped in self amalgamting
> tape to keep the weather out.
>
> How can I identify which is the cable that isn't working at the
> joins, without removing the SAT wrapping?


I haven't really understood this. is it that there are three different LNBs on the three cables but you don't know which is which at the receiver end? You could cover the LNBs one at a time with a metal box and see hiwch cable drops signal. Obviously the duff one is already dropped but this would tell which LNB is goes to.

Another htought: of it's wet that is causing the problem you migth find yo ucan spot the 'odd one out' just using a resistence meter.


Robert



Dave Liquorice

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Apr 26, 2012, 8:37:39 AM4/26/12
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On Thu, 26 Apr 2012 10:49:54 +0100, Fredxx wrote:

>> How can I identify which is the cable that isn't working at the
>> joins, without removing the SAT wrapping?
>
> I can't think of any other way than investing in investing in more self
> amalgamating tape and split the joints.

At last someone who has read the question. B-)

I think that is the only option as well but wanted to see if there
was something I hadn't thought of or how to kick the tone thrower
into working along the outside of coax.

Taking joints apart has 1:3 chance of getting the non-working cable
first time but I bet Sods Law will ensure I'll open up the two
working joints first. If the tone thrower still doesn't work at an
open joint it'll be a battery and meter job.

> Unless there's any way you could start from the dish side and follow the
> cable to the join?

Again taped together in a bundle and going over the apex of porch
roof that is not exactly accessable.

Yes, I have tried the duff feed in both inputs of the PVR and the
telly. I did half think about identing the cables yesterday but this
is only a temporary (now 7 months) arrangement. When I sort this out
I'll mark the ones I know.

--
Cheers
Dave.



Dave Liquorice

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Apr 26, 2012, 8:50:02 AM4/26/12
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On Thu, 26 Apr 2012 04:57:53 -0700 (PDT), RobertL wrote:

> I haven't really understood this. is it that there are three different
> LNBs on the three cables

One LNB with four independant outputs to feed the PVR (two LNB
inputs) and telly (one LNB input) one LNB output is unused. One of
the three cables isn't working. They all did before I fiddled... B-(

> Another htought: of it's wet that is causing the problem you migth find
> yo ucan spot the 'odd one out' just using a resistence meter.

I know which one at the receiver end is duff! B-) Each cable has a
joint in the middle of the run nicely done up in SAT. I want to know
which of these three joints is the one associated with the duff feed
so I can open it up and check it.

--
Cheers
Dave.



Mentalguy2k8

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Apr 26, 2012, 9:27:44 AM4/26/12
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"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
Re my post above, you've already got a perfectly good way to measure whether
each cable is working or not, since two of them have a perfectly adequate
signal running through them - a satellite TV picture feed. It's just a case
of taking the time to disconnect them all and try every re-connect
permutation while checking your TV screen to isolate which LNB output isn't
feeding a signal to which PVR input, and why.

Brian Gaff

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Apr 26, 2012, 9:57:33 AM4/26/12
to
I don't know what it might actually measure, but assuming its not a very
low value, measuring the resistance on all three might show one which is
significantly different.
However, I'm afraid in the end you will probably have to grit your teeth
and undo them. Make a note to mark them well before you make them again!

Brian

--
Brian Gaff - bri...@blueyonder.co.uk
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...

fred

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Apr 26, 2012, 10:02:52 AM4/26/12
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In article <nyyfbegfubjuvyypb...@srv1.howhill.co.uk>, Dave
Liquorice <allsortsn...@howhill.co.uk> writes
>On Thu, 26 Apr 2012 10:49:54 +0100, Fredxx wrote:
>
>>> How can I identify which is the cable that isn't working at the
>>> joins, without removing the SAT wrapping?
>>
>> I can't think of any other way than investing in investing in more self
>> amalgamating tape and split the joints.
>
>At last someone who has read the question. B-)
>
>I think that is the only option as well but wanted to see if there
>was something I hadn't thought of or how to kick the tone thrower
>into working along the outside of coax.
>
Order 5 rolls before tomorrow night and get free post from CPC ;-)
--
fred
it's a ba-na-na . . . .

John Rumm

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Apr 26, 2012, 10:13:14 AM4/26/12
to
On 26/04/2012 13:37, Dave Liquorice wrote:
> On Thu, 26 Apr 2012 10:49:54 +0100, Fredxx wrote:
>
>>> How can I identify which is the cable that isn't working at the
>>> joins, without removing the SAT wrapping?
>>
>> I can't think of any other way than investing in investing in more self
>> amalgamating tape and split the joints.
>
> At last someone who has read the question. B-)
>
> I think that is the only option as well but wanted to see if there
> was something I hadn't thought of or how to kick the tone thrower
> into working along the outside of coax.

I take it you have tried reversing the connections? Failing that, what
about connecting it between the screens of two of the co-axes rather
than the screen and inner of just one?



--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

John Rumm

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Apr 26, 2012, 10:15:33 AM4/26/12
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How does that help him identify which cable is the defective one at the
joint in the middle?

John Rumm

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Apr 26, 2012, 10:30:23 AM4/26/12
to
On 26/04/2012 14:57, Brian Gaff wrote:
> I don't know what it might actually measure, but assuming its not a very
> low value, measuring the resistance on all three might show one which is
> significantly different.

Likewise you could connect a power supply via an ammeter and see what
LNB current you can measure. If the co-ax is defective you may not have
a circuit... however it does not help identify which cable is which in
the middle of the run.

> However, I'm afraid in the end you will probably have to grit your teeth
> and undo them. Make a note to mark them well before you make them again!

Indeed...

Martin Brown

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Apr 26, 2012, 10:35:28 AM4/26/12
to
On 26/04/2012 10:06, Dave Liquorice wrote:
> Moved the DSAT only TV/PVR yesterday. Three coax's from the dish to
> the kit. All three worked before the move, one now doesn't. B-(
>
> There is a joint (F-type plugs and a coupler) in each coax outside
> that had been kept dry and ventilated in plastic bag open at the
> bottom. On inspection there was no sign of damp/corrsion etc in the
> joins. These joints are now exposed but wrapped in self amalgamting
> tape to keep the weather out.
>
> How can I identify which is the cable that isn't working at the
> joins, without removing the SAT wrapping?

Best I can think of is run a cable from ground at the faulty set end to
where your external connectors are and penetrate the SAT wrapping tape
with a pin to complete the circuit with a DVM on resistance. A quick
squeeze on the ones that it isn't should reseal the pinhole.

Murphy's Law says the faulty one will be the last one you test.

--
Regards,
Martin Brown

Martin Brown

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Apr 26, 2012, 10:41:16 AM4/26/12
to
On second thoughts you might be able to work it out non-invasively with
the same setup and a DVM on the capacitance range with a length of
aluminium foil wrapped around each of the contenders externally.

The right cable will have a significantly higher capacitance between its
internal shield and the external foil. Might be good enough to get it
with your signal tracer and a crystal earpiece.

--
Regards,
Martin Brown

Dave Liquorice

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Apr 26, 2012, 11:05:59 AM4/26/12
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On Thu, 26 Apr 2012 15:13:14 +0100, John Rumm wrote:

>> ... wanted to see if there was something I hadn't thought of or
how to
>> kick the tone thrower into working along the outside of coax.
>
> I take it you have tried reversing the connections?

Think so, I know I tried one connection only.

> Failing that, what about connecting it between the screens of two of the
> co-axes rather than the screen and inner of just one?

Thanks John, that's an idea. If that works and I detect the signal on
two cables I can move one thrower wire to the other and work out
which is the duffy one, or simply use the two good ones.

Something to play with whilst it's wet, cold and windy outside.

<later> Nawp doesn't work. B-( If I can detect the thrower at all
it's the same on all cables. I suspect that's because the screens are
all connected at the LNB, certainly the signal at the thrower
virtually disappears when you connect it two screens, as if shorted
out.

--
Cheers
Dave.



Bob Minchin

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Apr 26, 2012, 11:32:27 AM4/26/12
to
Pass a reasonable current between the braids of pairs of the three
cables and use a clamp on ammeter to see which cable pair has current
flow. Repeat for all 3 pairs and work out which cable is which.
Use AC or DC according to the type of clamp meter you use. DC is easier
as you can use a bench power supply on current limit but fewer clamp
meters work on DC.

Bob

Fredxx

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Apr 26, 2012, 12:31:43 PM4/26/12
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At the PVR end, have you measured the resistances of each cable, inner
to shield? And with reversing the DVM leads? The LNB should get power
so not a short. Similarly the 22kHz tone should make it's way to the
LNB for each channel. I'm just wondering if it's actually the LNB that
has failed on one output?

John Rumm

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Apr 26, 2012, 1:06:23 PM4/26/12
to
On 26/04/2012 16:05, Dave Liquorice wrote:
Can you disconnect them at the LNB?

Dave Liquorice

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Apr 26, 2012, 2:36:44 PM4/26/12
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On Thu, 26 Apr 2012 18:06:23 +0100, John Rumm wrote:

> Can you disconnect them at the LNB?

Also all done up in SAT... and because the sockets are rather close
together getting the SAT on neatly and well isn't easy. Also I rather
not go messing about with that ends as well. B-)

--
Cheers
Dave.



Rod Speed

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Apr 26, 2012, 3:55:26 PM4/26/12
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"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
Why cant you unplug them one by one at the LNB ?

Maybe you have those sealed up with tape too.

Alan

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Apr 26, 2012, 5:20:52 PM4/26/12
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In message <nyyfbegfubjuvyypb...@srv1.howhill.co.uk>, Dave
Liquorice <allsortsn...@howhill.co.uk> wrote
Could it be that you worked on the cables whilst the TV/PVR were still
switched on and supplying power to the LNBs? Have you tried swapping the
cables between equipment to see if the fault follows or are you just
assuming that, say, the input to tuner 1 on the PVR isn't working so one
cable is dead. If the latter, try turning off the equipment at the
mains plug for 30 seconds or so to see if a cold/hard boot cures the
problem

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

Mentalguy2k8

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Apr 26, 2012, 7:04:57 PM4/26/12
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"John Rumm" <see.my.s...@nowhere.null> wrote in message
news:e4mdnVN3yKcYxQTS...@brightview.co.uk...
> On 26/04/2012 14:27, Mentalguy2k8 wrote:
>>
>> "Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
>> news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
>>> On Thu, 26 Apr 2012 04:57:53 -0700 (PDT), RobertL wrote:
>>>
>>>> I haven't really understood this. is it that there are three different
>>>> LNBs on the three cables
>>>
>>> One LNB with four independant outputs to feed the PVR (two LNB
>>> inputs) and telly (one LNB input) one LNB output is unused. One of
>>> the three cables isn't working. They all did before I fiddled... B-(
>>>
>>>> Another htought: of it's wet that is causing the problem you migth find
>>>> yo ucan spot the 'odd one out' just using a resistence meter.
>>>
>>> I know which one at the receiver end is duff! B-) Each cable has a
>>> joint in the middle of the run nicely done up in SAT. I want to know
>>> which of these three joints is the one associated with the duff feed
>>> so I can open it up and check it.
>>
>> Re my post above, you've already got a perfectly good way to measure
>> whether each cable is working or not, since two of them have a perfectly
>> adequate signal running through them - a satellite TV picture feed. It's
>> just a case of taking the time to disconnect them all and try every
>> re-connect permutation while checking your TV screen to isolate which
>> LNB output isn't feeding a signal to which PVR input, and why.
>
> How does that help him identify which cable is the defective one at the
> joint in the middle?

LNB has 3 connected outputs (4 total) , 1, 2 and 3. Each cable goes into a
separate joint in the middle, then another 3 cables complete the feed to the
PVR.

Unplug all cables from PVR, connect cable 1 to PVR input 1, is there a
picture? He's only got one faulty feed, so if there is no picture, unplug
cable 1 from PVR input 1, plug cable 2 into PVR input 1. If there is still
no picture, PVR input 1 is faulty. If there is a picture with both feeds 1
and 2 in each PVR input, then PVR is OK and cable feed 3 must be faulty.

Leaving one *working* cable feed in the PVR, unplug all 3 cables from dish,
noting which one cuts the TV picture when disconnected, and mark each end
and the middle. Unplug working cable from dish and plug into dish outputs 2
and 3, checking whether the TV picture remains. If it does, the LNB/dish is
fine. If not, one LNB output has died, but if I understand correctly, he's
got a 4th LNB output so can use that instead of the faulty one.

If he then unplugs everything and plugs the other working feed into dish and
PVR, he'll be able to mark that cable at both ends and in the middle, too.
Therefore the unmarked cable is the faulty one.

Now we've got 3 working dish outputs and 3 working PVR inputs, problem is
somewhere in between. So by connecting the faulty cable from the LNB to the
PVR, we'll have no TV picture. So disconnect the middle connection of the
faulty feed which goes into the house, and connect it to one of the other
feeds from the dish, which we know are working. If the TV picture remains,
we know the stretch of cable between the dish and the middle joint must be
faulty. If the TV picture disappears, we know it must be the stretch of
cable between the middle connections and the TV indoors.


Mentalguy2k8

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Apr 26, 2012, 7:07:25 PM4/26/12
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"Mentalguy2k8" <Mental...@gmail.com> wrote in message
news:jnckau$db6$1...@dont-email.me...
* and of course the same principle of swapping around applies just in case
there's a fault in the middle connection hardware

John Rumm

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Apr 26, 2012, 7:21:35 PM4/26/12
to
The point of the exercise was to do it without unplugging the cables
anywhere other than at the receiver alas...

dennis@home

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Apr 27, 2012, 2:50:28 AM4/27/12
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"John Rumm" <see.my.s...@nowhere.null> wrote in message
news:mpCdnZRZV8gdRQTS...@brightview.co.uk...

> The point of the exercise was to do it without unplugging the cables
> anywhere other than at the receiver alas...

Its quite easy too..
just push a needle through the SAT and use a buzzer.
The needle hole should be easy to patch with a few mm of tape or may even
self heal.

Dave Liquorice

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Apr 27, 2012, 3:20:33 AM4/27/12
to
On Fri, 27 Apr 2012 00:21:35 +0100, John Rumm wrote:

> The point of the exercise was to do it without unplugging the cables
> anywhere other than at the receiver alas...

Aye and my grandma has quite enough eggs as well. B-)

--
Cheers
Dave.



Dave Liquorice

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Apr 27, 2012, 3:36:51 AM4/27/12
to
On Fri, 27 Apr 2012 07:50:28 +0100, dennis@home wrote:

>> The point of the exercise was to do it without unplugging the
cables
>> anywhere other than at the receiver alas...
>
> Its quite easy too..
> just push a needle through the SAT and use a buzzer.

Remember that all the screens are connected together at the LNB... I
very much doubt that an F-type coupler has gone open circuit on the
screen.

> The needle hole should be easy to patch with a few mm of tape or may
> even self heal.

This is true but I'm not sure it helps. Anyway it's just above
freezing, dry and fairly still this morning so I think it will be the
pick a joint and inspect until I find the duff one.

--
Cheers
Dave.



Mentalguy2k8

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Apr 27, 2012, 6:42:08 AM4/27/12
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"John Rumm" <see.my.s...@nowhere.null> wrote in message
news:mpCdnZRZV8gdRQTS...@brightview.co.uk...
AIUI, he's already de-weatherproofed the joints, so unplugging them isn't
going to make any difference, he's still going to have to re-protect them.
Whatever method he uses, he's going to have to expose *something* to test
each cable. It's a lot of buggering about but at least it only takes one
person and no special equipment.

John Rumm

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Apr 27, 2012, 8:39:49 AM4/27/12
to
Not at the time of writing yesterday... (he may have done by now however)

RobertL

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Apr 27, 2012, 8:48:26 AM4/27/12
to Dave Liquorice
now I understand.

My answer:

Disconnect the LNB and receivers. Poke a pin though the SAtape at the (halfway joins) to make contact with the outer of the F-plug. Look for the electrical continuity between this and one of the outers at the receiver.

If you don't have a meter with cables that reache that far then join two outers together at the rec end, then stick pins in halfway along to find which of the three is not joined to the others.

massage the SATape to cover pin holes afterwards.

Robert

Dave Liquorice

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Apr 27, 2012, 8:53:13 AM4/27/12
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On Fri, 27 Apr 2012 11:42:08 +0100, Mentalguy2k8 wrote:

>> The point of the exercise was to do it without unplugging the
cables
>> anywhere other than at the receiver alas...
>
> AIUI, he's already de-weatherproofed the joints,

No read the question in the orginal post:

"How can I identify which is the cable that isn't working at the
joins, without removing the SAT wrapping?"

Anyway sorted it now in the abscence of any pracical suggestions of
how to identify the non working cable without opeing up the joints
and the weather being good I went out earlier and opened 'em up and
yes the faulty one was the last one to be opened.

Some how one end of the cable had become partially unscrewed from the
F-type plug enough to make the inner open circuit in the coupler but
not enough for the cable to feel loose or fall out of the plug. The
coupler was buggered though, when trying to reuse I couldn't get the
core to go in very far and the thread was difficult to take up. So I
suspect with cold fingers the other day I gripped both the "nut" and
the knurled part of the plug when screwing the two together so as the
plug screwed onto the coupler it unscrewed from the cable. How I
didn't spot the 1/4" or so of exposed shiny braid on the black sheath
when I put the SAT tape on I do not know. At least all the cables are
now identified at both ends...

--
Cheers
Dave.



dennis@home

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Apr 27, 2012, 9:00:50 AM4/27/12
to


"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
> On Fri, 27 Apr 2012 07:50:28 +0100, dennis@home wrote:
>
>>> The point of the exercise was to do it without unplugging the
> cables
>>> anywhere other than at the receiver alas...
>>
>> Its quite easy too..
>> just push a needle through the SAT and use a buzzer.
>
> Remember that all the screens are connected together at the LNB... I
> very much doubt that an F-type coupler has gone open circuit on the
> screen.

So do I, that's why it should identify the cables with ease.
The faulty one is easy to find by just disconnecting them one by one and
watching the TV.



Mentalguy2k8

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Apr 27, 2012, 9:31:38 AM4/27/12
to

"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
> On Fri, 27 Apr 2012 11:42:08 +0100, Mentalguy2k8 wrote:
>
>>> The point of the exercise was to do it without unplugging the
> cables
>>> anywhere other than at the receiver alas...
>>
>> AIUI, he's already de-weatherproofed the joints,
>
> No read the question in the orginal post:
>
> "How can I identify which is the cable that isn't working at the
> joins, without removing the SAT wrapping?"

Fair enough, I was trying to help rule everything else out first, it may not
have been neccessary to uncover the joints if you'd found the fault
elsewhere.

>
> Anyway sorted it now in the abscence of any pracical suggestions of
> how to identify the non working cable without opeing up the joints
> and the weather being good I went out earlier and opened 'em up and
> yes the faulty one was the last one to be opened.
>
> Some how one end of the cable had become partially unscrewed from the
> F-type plug enough to make the inner open circuit in the coupler but
> not enough for the cable to feel loose or fall out of the plug. The
> coupler was buggered though, when trying to reuse I couldn't get the
> core to go in very far and the thread was difficult to take up. So I
> suspect with cold fingers the other day I gripped both the "nut" and
> the knurled part of the plug when screwing the two together so as the
> plug screwed onto the coupler it unscrewed from the cable. How I
> didn't spot the 1/4" or so of exposed shiny braid on the black sheath
> when I put the SAT tape on I do not know. At least all the cables are
> now identified at both ends...

And you don't need to remove/replace any buried cable.... great result. I
did a similar thing after we had a digital aerial installed, they hadn't
crimped the plugs onto the cable or tightened the nuts, so when I screwed
the nuts in, it just unscrewed the cable from the plug :(

John Rumm

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Apr 27, 2012, 10:42:04 AM4/27/12
to
On 27/04/2012 13:48, RobertL wrote:
> On Thursday, April 26, 2012 1:50:02 PM UTC+1, Dave Liquorice wrote:
>> On Thu, 26 Apr 2012 04:57:53 -0700 (PDT), RobertL wrote:
>>
>>> I haven't really understood this. is it that there are three different
>>> LNBs on the three cables
>>
>> One LNB with four independant outputs to feed the PVR (two LNB
>> inputs) and telly (one LNB input) one LNB output is unused. One of
>> the three cables isn't working. They all did before I fiddled... B-(
>>
>>> Another htought: of it's wet that is causing the problem you migth find
>>> yo ucan spot the 'odd one out' just using a resistence meter.
>>
>> I know which one at the receiver end is duff! B-) Each cable has a
>> joint in the middle of the run nicely done up in SAT. I want to know
>> which of these three joints is the one associated with the duff feed
>> so I can open it up and check it.
>
> now I understand.
>
> My answer:
>
> Disconnect the LNB and receivers. Poke a pin though the SAtape at the (halfway joins) to make contact with the outer of the F-plug. Look for the electrical continuity between this and one of the outers at the receiver.

This was suggested higher up the thread, but the same problem applied -
the LNB connections are also taped, and even harder to get at.

Dave Liquorice

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Apr 27, 2012, 11:06:23 AM4/27/12
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On Fri, 27 Apr 2012 15:42:04 +0100, John Rumm wrote:

> This was suggested higher up the thread, but the same problem applied -
> the LNB connections are also taped, and even harder to get at.

Yes, there does seem to be a remarkable amount of not reading the
question:

"How can I identify which is the cable that isn't working at the
joins, without removing the SAT wrapping?"

Going on. OK the LNB connections aren't mentioned but the orginal
post does say that everything was working before I remade the joints.
Slight possibilty of a knackered output on the LNB but very slight,
I'd still want to check the bits that have been fiddled with first.
Then work back to the LNB.

And who doesn't SAT wrap LNB connections? Cowboy installers who don't
crimp F-types I guess. B-)

--
Cheers
Dave.



John Rumm

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Apr 27, 2012, 12:37:49 PM4/27/12
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Some of the LNBs had a deployable "screen" that pulls down round all the
connectors. Might be ok in a sheltered location, but no use where there
is driving rain and wind!

dennis@home

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Apr 27, 2012, 1:28:15 PM4/27/12
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"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
> On Fri, 27 Apr 2012 15:42:04 +0100, John Rumm wrote:
>
>> This was suggested higher up the thread, but the same problem applied -
>> the LNB connections are also taped, and even harder to get at.
>
> Yes, there does seem to be a remarkable amount of not reading the
> question:
>
> "How can I identify which is the cable that isn't working at the
> joins, without removing the SAT wrapping?"

But the pin and buzz works if you measure the resistance and do it from the
PVR end to the joint.
Shame you didn't have a TDR to use, maybe its the next DIY job?

>
> Going on. OK the LNB connections aren't mentioned but the orginal
> post does say that everything was working before I remade the joints.
> Slight possibilty of a knackered output on the LNB but very slight,
> I'd still want to check the bits that have been fiddled with first.
> Then work back to the LNB.
>
> And who doesn't SAT wrap LNB connections? Cowboy installers who don't
> crimp F-types I guess. B-)

The last LNB sky put in had a cover for the cables and they didn't wrap
them.
Its still working after five years.

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