In article , starman
wrote:

Flander's Fartwhistle wrote:

DRM and it's digital broadcasting mode children will never appear
on shortwave. Mark it in your book. Analog will be here for a very
long time to come, as any digital dependent mode requires a clear
signal path for reception. When was the last time we heard a clear
shortwave program or station that had ZERO fading, noise or
propagation issues with it's signal? My guess is you can count them
on one hand.

A perfect example is how everyone has had to endure poor signal
degradation from someone using a modern cellphone. 20% of the calls
I get from people out in the field usually cut out or are partially
garbled, and I am using a brand new Samsung and Nokia digital
phone. Any loss of "data" between you and 'over there/wherever' on
the other end of the cellphone line and your call is useless or
interrupted. If it's this bad with local Verizon cell phone
service in a major metro area (NJ/NY/Ct) then how bad will it be
with a digital shortwave signal comming halfway around the world on
a much lower frequency prone to atmospherics and other
degradation...?

Digital Shortwave???? Sounds alot like New Coke or the Yugo car or
any one of another 'brilliant' consumer technology or product ideas
that are now in the rubbish bin of history.

The success of DRM doesn't depend on perfect propagation conditions.
If it did, the proponents of this technology wouldn't consider using
it for ionospheric propagation. It's a matter of how degraded the
conditions can be before the digital signal can not be decoded
properly. DRM has considerable tolerance for poor propagation. The
cell phone comparison is apples and oranges. They are two very
different technologies and frequency ranges. If DRM fails to catch
on, it will most likely be because people don't want to buy new
receivers for international broadcasting when it appears to have an
uncertain future at this time.

The FEC in DRM is pretty weak. FEC in stable medium just to overcome the
stable defects needs to be about 1/3 of the transmitted overhead. DRM
does not even provide this much for a non stable path and so it is
completely inadequate for HF propagation. DRM on SW is not unlike
pounding screws into wood with a hammer instead of using a screw driver.
The hammer will pound in the screws just like a nail but you will not
derive the benefit of using the screw over the nail for greater
fastening power by pounding it in with the hammer.

The wheels came off this technology before it even got started.

DRM - the claims amount to a Michael Bryant type of non reality.

--
Telamon
Ventura, California