On 04/02/2018 04:35, wrote:
tabb wrote:
It was, it only allowed 5 channels.

No it didn't. With 8MHz per channel and an empty channel between each
used channel it allowed 24 channels.

That is not the same as building an entire *network* with lots of
channels. When the UK was developing colour TV transmission here they
were thought to be over egging it by most of our continental neighbours,
because they were designing the system to support two channels with the
possibility of expansion to a third. Most other countries were designed
for one, with an expansion option to a second.

When you take into account the inability to tolerate multipath at the
receiver, and the relatively coarse filtering available at the
transmitters of the day, you romp through available/useable channels
very quickly.

Adding channel 4 was quite a technical challenge, and channel five was
never really possible to do completely, and even then it required use of
channels previously set aside for other applications.

Where I lived I could easily pick up about 12 channels.

And how many of those were ostensibly a duplicate channel from a
different transmitter? Also keep in mind that the whole populous does
not live in your street! Some areas posed a far more complicated
geographical challenge to getting proper coverage with just the three
main channels.



--
Cheers,

John.

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