Smart Meters
CALMU Smart meters are not a new idea. I was a member of a project in the early 1980s which designed and rolled out a prototype smart meter which was far ahead of it’s time. The unit was called a CALMU (Credit and Load Management Unit). It was capable of recording electricity consumption with several tariffs, gas consumption, with a connection to a suitable gas meter and water use, with a connection to a suitable water meter.
Read more →Mullard 5-20 Amplifier
Many years ago one of my brothers’ friends brought me a faulty military surplus valve amplifier which used 807 valves for the output. It appeared to have suffered a flashover which had destroyed much of the wiring and components inside the chassis, but the tagboards appeared to be reusable. I had a copy of a Mullard amplifier book, Mullard Circuits for Audio Amplifiers at the time, which I subsequently lent so someone who never returned it.
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