<p>➀ The English Electric Valve Co. has announced the first British commercially available high-vacuum variable capacitors; </p><p>➁ The capacitors, introduced 64 years ago, offer voltage ratings of 15kV, 8kV, and 10kV, with various capacitance ranges; </p><p>➂ The use of high-vacuum dielectric reduces plate spacing, leading to a compact design and lower stray capacitance and inductance.</p>