Economy 7

[JohnW2]

Surely Economy 7 is the system. The tariff can be increased (price rise).

Well, it's one of those situations in which we all know the situation, and what is being said, so I'm not sure that the words matter too much.

I guess it depends upon what one means by 'the system'. The electricity supply to the property is obviously the same whether it is E7 or not. It's the meter and any load switching which turn it potentially into an 'E7 system' - but, as has been said, there are different flavours of E7.

However, I think it's understandable that eric regards E7 as a 'tariff - since the tariff doesn't just determine 'a price', but it determines the prices for peak and off-peak electricity. If, hypothetically, those two figures were the same, then it wouldn't be functionally E7, even if 'the system' (meter etc.) was "E7" - so it could be said that, by specifying a lower price for off-peak electricity, the tariff is, in some senses, what makes it (functionally) E7!

Kind Regards, John

 

[winston1]

Or when BBC R4 LW ceases transmission, since the necessary spare parts for the transmitters have almost run out (controversial).

Very controversial as spares are still manufactured. Maybe the current providers don't have much stock, but that is not the same thing.

 

[JohnD]

is somebody making the big valves again? I heard there were only about five in the world.

 

[JohnD]

here...

maybe things have moved on

https://www.theguardian.com/media/2011/oct/09/bbc-radio4-long-wave-goodbye

"A handful of specially crafted glass valves each measuring one metre high are all that is stopping the historic home of Test Match Special, Yesterday in Parliament and the Daily Service going suddenly and permanently off air.

BBC Radio 4 long wave, which transmits on the 198 kilohertz frequency, relies on ageing transmitter equipment that uses a pair of the valves – no longer manufactured – to function.

The valves, at Droitwich in Worcestershire, are so rare that engineers say there are fewer than 10 in the world, and the BBC has been forced to buy up the entire global supply. Each lasts anywhere between one and 10 years, and when one of the last two blows the service will go quiet."

 

[JohnW2]

.... The valves, at Droitwich in Worcestershire, are so rare that engineers say there are fewer than 10 in the world, and the BBC has been forced to buy up the entire global supply. Each lasts anywhere between one and 10 years, and when one of the last two blows the service will go quiet."

This is all very well, but, in my opinion, it's a bit of a lame excuse.

It might well be that the BBC has bought up all existing stock of these valves, and maybe even true that it would be catastrophically expensive to commission someone to make some more. However, we have not lost our ability to design and construct high-powered transmitters, even if they would not today utilise massive thermionic valves.

Kind Regards, John

 

[winston1]

Indeed. Algeria recently replaced its LW Tx on 252kHz with a new solid state one.

By the way the BBC does not own or operate the transmitters any more so why would they buy up the stock? Don't believe all you read in newspapers.