splitting an aerial 6 ways?
 

Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.

splitting an aerial 6 ways?
 

In message , Raymondo writes
Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.

There may be some splitters with a marginally better spec, but this one
seems fine. I certainly wouldn't bother chasing a better one.

The insertion loss is 12dB (which is typical), so you'll need to replace
your 24dB with a 12dB. However, rather than fitting a single 12dB
attenuator at the input, it might be 'better' practice to fit six
individual attenuators (still 12dB) at the output side (to ensure that
all ports are well-matched under all conditions). But, to be honest, a
single input attenuator is cheaper, and will work OK.
--
Ian

splitting an aerial 6 ways?
 

I don't know about modernsets, but I found that having too many sets only
isolated by passive splitters, resulted in patterning on signal when some
sets were on some channels. Quite what effect any low levels of interaction
might have on digital signals, I do not know.
Brian
"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point
from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.

splitting an aerial 6 ways?
 

In message , Brian Gaff
writes
"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point
from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.


I don't know about modernsets, but I found that having too many sets only
isolated by passive splitters, resulted in patterning on signal when some
sets were on some channels. Quite what effect any low levels of interaction
might have on digital signals, I do not know.
Brian

If this happened with digital signals (for example, if the local
oscillator of one TV set or set-top box fed back up the aerial input
feed to the splitter and, because of inadequate isolation, then emerged
as an interfering signal from the other outputs), presumably it would
reduce the BER of the signal. This wouldn't cause pattering, but could
kill all the channels carried by one of the multiplexes - or at least,
cause blocking.

My suggestion to fit individual 12dB attenuators on each output (or at
the TV end) will provide an additional 24dB of isolation between output
ports (which could certainly eliminate any such problems).
--
Ian

splitting an aerial 6 ways?
 

"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point
from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.

Your logic is impecable. I would use an eight way splitter. At UHF the loss
on a 6 way is about 10dB and on an 8 way about 12dB. An 8 way would give you
two spares. There's no need to terminate these, really. 24dB of attenuation
seems a lot. I should try the splitter with no attenuation first, and
possibly add a 6dB atten if necessary.

Bill

splitting an aerial 6 ways?
 

In article ,
says...

"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point
from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.

Your logic is impecable. I would use an eight way splitter. At UHF the loss
on a 6 way is about 10dB and on an 8 way about 12dB. An 8 way would give you
two spares. There's no need to terminate these, really. 24dB of attenuation
seems a lot. I should try the splitter with no attenuation first, and
possibly add a 6dB atten if necessary.

Bill

As you (presumably) only have one outlet at present but now want to
increase this sixfold, perhaps you might want to consider a future
proofing exercise in case there is another demand explosion later on?

Rather than an 8-way splitter, how about an 8-way tap? A 20dB tap
provides lots of isolation and has an output with only 2dB loss (which
MUST be terminated if not in use) which could feed 17dB tap in the
future to give a further 8 outlets with a similar output level, etc.,
etc.

Blakes have a suitable range:

http://www.blake-uk.com/page/amplifi...eption_protaps

A 3dB pad on the input would restore the attenuation level.

However, as Bill says, 24dB of attenuation does seem rather a lot - it
might be a good idea to experiment a bit to see what minimum attenuation
is needed and plan again on that basis.

Another advantage of using taps is that they can be tailored to suit
different cable lengths - I think it unlikely that all 6 outlets will
need the same length of cable.

Say 2 of your new feeds are the same length as the existing one but the
other 3 are some distance away and need an extra 25 metres of cable.
Allowing about 20dB/100metres @860MHz for WF100 cable, that's 5dB loss.
A 4-way 20dB tap feeding a 17dB tap will give the same levels at each
outlet. If the 3 long feeds are located close to each other, you could
move the 17dB splitter to a suitable common point and feed it with a
single cable.

The results would be the same but you would use a lot less cable which
could be important if you are tight for space on your cable run (as well
as saving money, of course!)

Note that there appears to be a mistake on Blake's web site - I think
the proTAP4xx series should be shown as 4-way taps, not 3.

The pdf version of their catalogue is correct:

www.blake-uk.com/downloads/catalogue.pdf

--

Terry

splitting an aerial 6 ways?
 

"Ian Jackson" wrote in message
...
In message , Brian Gaff
writes
"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a
better
My suggestion to fit individual 12dB attenuators on each output (or at the
TV end) will provide an additional 24dB of isolation between output ports
(which could certainly eliminate any such problems).
--
Ian

I think we're solving a problem that doesn't exist here. Those inductive
splitters generally isolate by about 18-20dB between ports. You have to add
the downlead loss (interferer to splitter) to that.

Of course, having said that, if the s/n ratio of a mux was (unavoidably)
marginal, any little bit of crap could make things significantly worse.

Bill

splitting an aerial 6 ways?
 

"Terry Casey" wrote in message
om...
In article ,
says...
As you (presumably) only have one outlet at present but now want to
increase this sixfold, perhaps you might want to consider a future
proofing exercise in case there is another demand explosion later on?

Rather than an 8-way splitter, how about an 8-way tap? A 20dB tap
provides lots of isolation and has an output with only 2dB loss (which
MUST be terminated if not in use) which could feed 17dB tap in the
future to give a further 8 outlets with a similar output level, etc.,
etc.

My own way of doing this would be to fit a two way splitter on the aerial
feed. One leg terminated for future use; the other to feed the 8 way
splitter. We all have our own funny little ways!

Bill

splitting an aerial 6 ways?
 

"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a better
type?

http://tinyurl.com/nboxys

I live 4 miles from winter hill and have a clear view of the mast from the
roof aerial. I currently have an attenuator fitted which is 24db. If I
remove the attenuator and then go thro the splitter taking in to
consideration the new insertion loss (around 15db) and feed each point
from
there in theory I should have a stronger signal than I had before, then if
necessary I could fit a milder attenuator to the splitter input if
necessary, is that correct?

Thanks in advance.


Use the splitter shown.

Fit a 12db attenuator for now, but remove it when analog switches off on 5th
November.

splitting an aerial 6 ways?
 

In message , Bill Wright
writes

"Ian Jackson" wrote in message
...
In message , Brian Gaff
writes
"Raymondo" wrote in message ...
Will this be ok for splitting an aerial 6 ways or should I go for a
better
My suggestion to fit individual 12dB attenuators on each output (or at the
TV end) will provide an additional 24dB of isolation between output ports
(which could certainly eliminate any such problems).
--
Ian

I think we're solving a problem that doesn't exist here. Those inductive
splitters generally isolate by about 18-20dB between ports. You have to add
the downlead loss (interferer to splitter) to that.

Of course, having said that, if the s/n ratio of a mux was (unavoidably)
marginal, any little bit of crap could make things significantly worse.

These days, I'm not sure how much local oscillator comes out of the
aerial input of digital TVs and STBs - or even what the frequencies are
(do they still use the 'traditional' 38.9MHz IF?). It's just that Brian
Gaff suggested that isolation (or lack of) could be a potential problem,
and I remembered that as well as ensuring a better impedance match (by
using individual attenuators on the output side of the splitter), this
also improves the port-to-port isolation.

Of course, another reason for using individual attenuators (at the TV
end) is to keep the signal level on the drop cables as high as possible.
This will minimise the effects of interference from ingress.

While all of this is probably a lily-guilding competition, it's always
worth thinking of the solution which gives the best results. You can
then think of reasons why not to implement it!
--
Ian