Si4734 LW/MW/FM/SW 20 band radio receiver.

Kaynak dosya ve PCB linkleri
https://disk.yandex.com.tr/d/Y8FFnP6ya_djQA
https://disk.yandex.com.tr/d/imCxQ_mVU-gs0w
https://pu2clr.github.io/SI4735/
https://pu2clr.github.io/SI4735/extras/apidoc/html/
https://stringfixer.com/tr/Vestigal_sideband

Hello to everyone,

In this video, I will try to introduce you to a radio receiver that I have been working on for a while. There are many chips produced by Silicon Lab for radio receiver and transmitter circuits. I tried the si4825 chip of the same company beforehand. This chip, which you can listen to FM medium wave and short wave bands, does not need any software. There are also many videos about the making of hearing.

The subject of this video is the Sİ4734 produced by the same company. The reason I chose it was that it was cheaper than the others. Its features are almost the same as the Sİ4735, but there are minor differences. If you want to listen to the entire shortwave band with SSB and CW broadcasts, you should choose the Si4735, which offers BFO support. .At the same time, this chip also has an RDS feature. In this way, you can see the digital information flow of radio stations (weather and road conditions, traffic conditions, song information playing on the radio, etc.) in FM broadcasts.

I built the circuit on the test board. The only difficulty was to solder the si4734 in the SMD case to the smd/dip converter adapter. You may need a good magnifying glass for this. There is not much difficulty in its construction. I leave the arduino code and source files I used under the video.

With this receiver, you can listen to radios broadcasting in FM (88-108 Mhz), Medium Wave (520-1720 Khz), Long Wave (150-510 Khz) and Short Wave (1.8 Mhz-28.4Mhz) bands.

n addition to FM and Shortwave broadcasts, it is possible to listen to stations broadcasting in Long Wave and Medium Wave bands. In our country, except for FM broadcasting, only the Voice of Turkey is in the Short Wave band.
Its radio has Turkish broadcasts. There are still stations broadcasting in the Medium Wave band in Europe, America, the Middle East and the Far East.

I had a medium and long wave radio antenna that I took from an old stereo. I added these to the circuit, but if you live in Istanbul, it is not possible to listen to many stations. You can catch broadcasts more easily in coastal cities and high places.

I also prepared the PCB. Anyone who wishes can build the circuit on the PCB. The circuit is fed with a maximum of 5.5 volts. Be careful not to exceed this voltage. I did not put an amplifier stage on the PCB. You can add ready-made kits (for ex. PAM8403). I left an empty space for this.

While listening to stations broadcasting Amplitude Modulation (Long Wave, Medium Wave and Short Wave band)
AGC (automatic gain control) should be turned off. When you find a station, you can activate AGC to stabilize that signal (on). Again, you can fine-tune the frequency ranges of 1, 5 and 10 steps with the STEP button during the station search. . With the BW(Band Width button), you can change the audio frequency intonation of the Amplitude Modulated signals.

SSB (Single Side Band)-Single Side Band modulation is the technique of transmitting only half of the audio signals that we know as sinusoidal forms, by filtering. .If the receiver (transmitter) does not have this circuit, we hear the incoming (outgoing) signals intermittently and like the sound of a frog.