On 2006-06-05, Christian McArdle wrote:
It only costs a dB or two to have a wideband, and it is very
good insurance.

I think you'll find in general Christian, its more than that in a lot of
instances!..

Not necessarily. Indeed, take the Blake DMX10A (Band A) mentioned earlier.
According to Blake, it has 12.89dB gain, just 0.29dB more than the DMX10WB
(Wideband) at 12.60dB.

This is not a valid comparison for receiving group A signals. Because:

1. TV aerial gain is not constant over its rated bandwidth

2. "Official" aerial gain figures are usually the peak gain value

3. Peak gain for a WB aerial is typically at the top end of the UHF band

4. Group A frquencies are at the bottom end of the UHF band so you
will not get close to the WB aerial's "official" gain figure for
signals in group A.

In actual practice the DMX10WB will be 3 or more dB worse *for signals in
group A* than the DMX10A. If you are receiving a grouped set of signals
it is certainly true that a matching grouped aerial will be better than
a wide band aerial.

Right now with many parts of the country only marginally covered until
the transmitter power is increased by region over the next few years an
aerial that has 3 dB better gain may make the difference between good
and poor reception.

--
John Phillips