Marked: "DAYRAD Tube Checker / Mfd. by the Radio Products Co., Dayton, Ohio. / Licensed Under Weston Patent 1704566 Type B". Includes leather carrying strap. Tube tester designed for A.C. plug in ...

Abstract: In order to solve the phenomenon of heavy passenger flow in the metro station during the peak commuting period, the metro operating company tries to improve the metro capacity by shortening ...

If you’re planning on hosting large gatherings during the next few months, you’ll want to invest in a powerful vacuum that can tackle big messes without being a pain to use. If you’re on the market ...

Abstract: In this letter, we demonstrate a PDMS/GaN-based optical microsensor for measuring vacuum pressure. The submillimeter-sized GaN device responsible for optical emission and detection is ...