Month: January 2026

With the insights from part 1 it is clear that we need a circuit which can produce the modulated signal: s(t)=Accos⁡(2πfct)⋅(1+km(t)) After some searching and consideration I found the AD633 from Analog Devices which is an analogue multiplier with differential inputs which does the following: From the figure one can see that it basically performs…

I posses a number of very old radio receivers from the beginning of the last century – truly beautiful artefacts from the dawn of wireless communication and I have restored them all to working condition, see below. These old receivers were mainly built to receive radio broadcasts on very low frequencies, i.e. Long Wave or…