Marconi Scientific Instrument Ltd. radio from 1922 скачать в хорошем качестве

Marconi Scientific Instrument Ltd. radio from 1922

A previous video of this radio showed it receiving the Radio 4 close down. This is an extended video showing it receiving multiple stations. The radio is first tuned into Radio Wales, then into Radio 5 Live (both on medium wave). Radio 5 Live is very close to Radio Wales and is quite difficult to completely tune out on a radio of this date (to improve selectivity I greatly extended the length of the aerial). I have also put it onto a trolley so that it can be turned around to show the "insides". The valves are turned off during this, as when hot the filaments are very delicate. After this the radio is tuned into Radio 4 on long wave. This radio was designed for experimenters, so pretty much every aspect of the set was provided with a panel control. This includes 5 filament controls. These were essential for bright emitter valves, as the filament resistance is much lower when cold, so the switch on current must be limited to avoid over-running the valves. There is a main filament control, plus additional controls for the first and second HF amplifiers, the detector valve (rectifier on the panel) and a single control for the note magnifiers. Additional panel controls consist of the grid potentiometer, the aerial and anode tapped inductances, the aerial and anode tuning capacitors, the reaction control (regeneration) and various switches (0, 1 or 2 note amplifiers, headphones or loudspeaker). The insides show the three main inductances (plus the reaction coil), the filament rheostats, and the aerial tuning capacitor. The anode tuning capacitor is mostly hidden. This is highly unusual for 1922 as it is "ganged", controlling both HF tuned circuits with the same control. Mostly hidden in the bottom of the cabinet are the two inter-valve transformers. Since the last video I have obtained two additional working V24 valves. These show improved gain compared to the previous video. Enjoy!