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[Marks DTM Calib]

It is unlikely to make any difference when it goes digital as somewhere theere will be a Tv transmitter with the same frequencies as the ones used by your local station.

[Martin_1962]

Nah....you use a multi element array......this results in the interference signal being cancelled out.  

Its an old technique they also used on some early radar to try to get round jamming etc and works well for TV

How does this work then - when EM C4 is the same frequency as SC Mux1 and in a very similar direction?

[Martin_1962]

That'll explain why the freeview has gone tits up and the sky is working fine then

Is is going to be a big problem when all TV goes digital? Before wh had sky we were on the old digital set up and often lost the signal due to certain weather conditions. To be honest it is about that is stopping me from dumping sky

No because the jamming stations will be closed down - in SC EM situation there will be no shared channels post DSO

[TheBoy]

My TV never seems to suffer (only ever watch freeview), in fact not really suffered since the CB days...

[Kevin Wood]

Plenty of ham radio activity around europe on VHF / UHF tonight by the looks of things.

"Put those damned antennas up" moves up a notch on Kevin's TODO list.

Kevin

[Marks DTM Calib]

Nah....you use a multi element array......this results in the interference signal being cancelled out.  

Its an old technique they also used on some early radar to try to get round jamming etc and works well for TV

How does this work then - when EM C4 is the same frequency as SC Mux1 and in a very similar direction?

Because the interfering signal has a number of multipaths reaching your location which will be in and out of phase with each other due to it having travelled a long distance down a wave guide......add and subtract the signals on the antenna arrays in the correct manner and the interferring signal is cancelled out!

The wanted signal is line of sight which will be the dominant reception peek.....it will be unaffected

[Marks DTM Calib]

That'll explain why the freeview has gone tits up and the sky is working fine then

Is is going to be a big problem when all TV goes digital? Before wh had sky we were on the old digital set up and often lost the signal due to certain weather conditions. To be honest it is about that is stopping me from dumping sky

No because the jamming stations will be closed down - in SC EM situation there will be no shared channels post DSO

There will....given the large number of transmitters in the Uk and the small number of mux frequencies there will always be overlap.

It wont go post digital and as discussed before, digitl is more prne to multpath interference where as on analogue it would ahev been seen as a ghost image.

[Martin_1962]

Nah....you use a multi element array......this results in the interference signal being cancelled out.  

Its an old technique they also used on some early radar to try to get round jamming etc and works well for TV

How does this work then - when EM C4 is the same frequency as SC Mux1 and in a very similar direction?

Because the interfering signal has a number of multipaths reaching your location which will be in and out of phase with each other due to it having travelled a long distance down a wave guide......add and subtract the signals on the antenna arrays in the correct manner and the interferring signal is cancelled out!

The wanted signal is line of sight which will be the dominant reception peek.....it will be unaffected

Want to have a go then?

Too high for me!

Looks like 5 degree or so difference

[Martin_1962]

That'll explain why the freeview has gone tits up and the sky is working fine then

Is is going to be a big problem when all TV goes digital? Before wh had sky we were on the old digital set up and often lost the signal due to certain weather conditions. To be honest it is about that is stopping me from dumping sky

No because the jamming stations will be closed down - in SC EM situation there will be no shared channels post DSO

There will....given the large number of transmitters in the Uk and the small number of mux frequencies there will always be overlap.

It wont go post digital and as discussed before, digitl is more prne to multpath interference where as on analogue it would ahev been seen as a ghost image.

Looking at the channels - the only real problem around here is Emley

[Marks DTM Calib]

That'll explain why the freeview has gone tits up and the sky is working fine then

Is is going to be a big problem when all TV goes digital? Before wh had sky we were on the old digital set up and often lost the signal due to certain weather conditions. To be honest it is about that is stopping me from dumping sky

No because the jamming stations will be closed down - in SC EM situation there will be no shared channels post DSO

There will....given the large number of transmitters in the Uk and the small number of mux frequencies there will always be overlap.

It wont go post digital and as discussed before, digitl is more prne to multpath interference where as on analogue it would ahev been seen as a ghost image.

Looking at the channels - the only real problem around here is Emley

Today possibly.

What you ahev to remember is that after the analogue switch off most of the digital multiplexers are being moved to occupy the old analogue frequencies.....

....plus some extras (there are far more multiplers than the 5 analogue channels)

So it will probably just be another one causing the issues!

[Martin_1962]

Seen the post switch off allocations, should be fine, only Emley was anywhere near the power of Sutton.

That said I once picked up Newcastle DTTV

[Marks DTM Calib]

The trouble with the ducting is that power has little to do with it as the attenuation is small!

So you can get trouble with low power repeaters!

[Martin_1962]

The trouble with the ducting is that power has little to do with it as the attenuation is small!

So you can get trouble with low power repeaters!

In the rough direction there is only Sutton Emley and Newcastle which are horizontal, vertical seems to have no effect

[Marks DTM Calib]

The trouble with the ducting is that power has little to do with it as the attenuation is small!

So you can get trouble with low power repeaters!

In the rough direction there is only Sutton Emley and Newcastle which are horizontal, vertical seems to have no effect

Yep but your aerial will also have side lobes and receive off the rear....

[Martin_1962]

The trouble with the ducting is that power has little to do with it as the attenuation is small!

So you can get trouble with low power repeaters!

In the rough direction there is only Sutton Emley and Newcastle which are horizontal, vertical seems to have no effect

Yep but your aerial will also have side lobes and receive off the rear....

Not when there is a big hill between us and Rigde Hill