I want to make a radio antenna at home which will be able to receive all FM frequencies for my FM radio or Android FM. How do I make it?
Frequency it can catch : 88 - 108 MHz
Common receiver antennas for the FM broadcast band (88-108 MHz) are typically center-fed folded dipoles roundly 1.5 meters long (half wavelength for the ~100 MHz center frequency of the band); they're made from twin-lead (flat, like old fashioned TV antenna cable) cut to length, conductors joined at the ends, and one conductor cut at the center and joined to a similar length of twin-lead feed line -- at DC, this forms a simple loop. In practice, a long wire, up to about ten wavelengths (thirty meters) will do at least as well, but isn't as compatible with an indoor installation.
Adding an antenna to an Android device, however, isn't as simple as hooking up a wire antenna. Most such devices have no provision for an external antenna, or any connector for one (in a phone designed more than five years ago or so) is likely to be hidden inside the back cover of the device. Many modern Android devices use fractal antennas to give the effect of a resonant antenna for the cellular communication frequency (much higher than FM broadcast, though it varies by phone make/model and cell provider), and some of the more popular current models have deleted the FM radio receive capability in hardware (my first-gen Pixel, for instance, lacks the FM chip).