How to make homemade FM radio - simple DIY auto scan 100% working on a breadboard
40The details can be found on http://howtodosteps.blogspot.com/2018/02/home-made-diy-how-to-make-auto-scan.html
Radios might seem super high-tech. Here is a complete guide how to make it at home for less than $10 way cheaper than you think
Prototype demonstration how to make auto-scan FM radio receiver that does not require antenna coil like the analog radio. This is way simpler because the microchip itself control the signal and you can tune in to FM frequency using a click of a button.
WHAT YOU’LL NEED for the auto-search radio circuit
1 x BK1079 radio chip - The heart of the circuit is BK1079 radio microchip and it consists for RF Low Noise Amplifier (LNA), Analog / Digital Phase Lock Loop as well as Analog / Digital signal converter built in its internal structure. You don't have to make coil winding antenna and to make it work and to have a better reception just add in crystal oscillator into the circuit to produce the digital phase lock loop which combined with the analog phase lock loop.
1 x 100 nH - inductor
1 x 18 pF ceramic capacitor
1 x 100 nF ceramic capacitor
1 x 10 uF electrolyte capacitor
3 x 10 kOhm resistors
3 x push button (reset, seek, and volume) - you can use another 2 additional push button for seeking down and volume down. But for demonstration purposes, we just use 1 to seek/search up and 1 for volume up only. Otherwise, you can just reset if you want to go back.
1 x antenna (simple) - any antenna will do even a piece of wire will work. To make it perfect perhaps you can use a germanium diode between the antenna and the circuit as the germanium diodes are very receptive toward radio signal
2 x AA Batteries (3 volt DC) - Do not go over 5 volt and it will fried the circuit.
Step 1: Note that the BK1079 is an SMD package SOP-10 which you will need to convert to through hole board for prototyping. Therefore you will need SMD to through hole converter board which you can find on eBay which is very cheap. You can get 10 pieces for $2 USD. Otherwise, you can prototype it on SMD circuit board
Step 2: Assemble all the necessary components based on the circuit go with the BK1079 first then the inductor, capacitors, resistors. The push button is difficult to stick it on the breadboard - so you will need to solder it on permanent board with pin connector so that it can be easily connected later using breadboard jumper wire Male - Female.
Step 3: Connect the circuit to 3 Volt battery and test to search radio channel. You can easily capture the available FM radio channel that is reachable even in a closed-door room.
This demonstration work perfectly and if you want to build FM radio you don't have to do a lot of experimentation to measure the signal strength whatsoever as long as you are within the distance to receive radio signal the auto scan will seek all the frequency channels automatically.
#Howto #DIY #HomeMade #radiocircuit #electronicfordummy