from alt.radio.digital: Calling Bill tvaerialguy

Pity the best stuff is discussed in other newsgroups.

Within alt.radio.digital, Bill of added
the following to the British audience:
Bill, Nicolas Croiset says that DVB-T receivers cannot cope with
echoes. As you've installed many DVB-T receivers in the UK I'd like
to ask your opinion of how well, or otherwise, DVB-T copes with
multipath reception.

In practical terms the answer is roughly as follows. If signal
strength is pretty good (say 10dB above digital threshold) then quite
severe short delay analogue ghosting will equate to few if any
problems for DTT reception. By 'quite severe' I mean that the
ghosting would be visible all the time, but the picture would be just
about 'watchable' although pretty annoying. If the ghosting is really
severe, with the picture breaking up and two or more images of
more-or-less equal strength, then the DTT will start to crumble and
might be totally useless. In theory this shouldn't happen with short
delay reflections, but in practice it does.
If signal strength is only just above threshold the toleration of
multipath is less.
All this assumes that the digtal/analogue comparison is valid, so the
channels must all be in the same group.
Very long delay multipath at any sort of strength is very rare, but
it can have a disasterous effect on DTT I'm told. I've never seen
this though.
A more common problem is erosion of the c/n ratio due to a co-channel
analogue signal. We suffer this in the north midlands (Emley Moor
versus Sutton Coldfield). This can really be a killer.

Bill

Look at the seller tvaerialguy on eBay. I'll be very interested to
see if that orange housing sells. It must weigh a ton!

Pity the best stuff is discussed in other newsgroups.

Within alt.radio.digital, Bill of added
the following to the British audience:
Bill, Nicolas Croiset says that DVB-T receivers cannot cope with
echoes. As you've installed many DVB-T receivers in the UK I'd like
to ask your opinion of how well, or otherwise, DVB-T copes with
multipath reception.

In practical terms the answer is roughly as follows. If signal
strength is pretty good (say 10dB above digital threshold) then quite
severe short delay analogue ghosting will equate to few if any
problems for DTT reception. By 'quite severe' I mean that the
ghosting would be visible all the time, but the picture would be just
about 'watchable' although pretty annoying. If the ghosting is really
severe, with the picture breaking up and two or more images of
more-or-less equal strength, then the DTT will start to crumble and
might be totally useless. In theory this shouldn't happen with short
delay reflections, but in practice it does.
If signal strength is only just above threshold the toleration of
multipath is less.
All this assumes that the digtal/analogue comparison is valid, so the
channels must all be in the same group.
Very long delay multipath at any sort of strength is very rare, but
it can have a disasterous effect on DTT I'm told. I've never seen
this though.
A more common problem is erosion of the c/n ratio due to a co-channel
analogue signal. We suffer this in the north midlands (Emley Moor
versus Sutton Coldfield). This can really be a killer.

Bill

Look at the seller tvaerialguy on eBay. I'll be very interested to
see if that orange housing sells. It must weigh a ton!