FM radio receiver circuit

[wzhe6095]

Hi, all
I want to learn how to design high frequency circuit, so I draw this FM radio receiving circuit, could you give me some advise to revise it?
How to do PCB layout and routing, could you give me some materials.

Thanks!
Sincerely,

zhe

 

[Ogu Reginald]

PCB softwares differ slightly from each. Go to the help icon in the window of the software you are using and you will see how to work with the PCB software.

In doing PCB for high frequency circuit, please make sure that you place components as close as possible to make the lenght of the tracks as short as possible because two parallel tracks may form capacitance and as you know a capacitor is frequency dependent.
There is also a method whereby the tracks can be designed and used as antenna.

 

[Audioguru]

It looks too simple to be an FM receiver circuit. Is it the horrible TDA7000 or newer and also horrible TDA7088 IC?
An FM "radio" with it, headphones and a battery are sold for only ONE DOLLAR at The Dollar Store. Its performance is awful.

 

[wzhe6095]

Thank u for answer, it is CD2003GP, TDA2822M. i haven't put the battery and headphones in this circuit, but the interface is reserved.

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hi, Ogu Reginald,

Thank u for answer, your suggestion may be useful.

zhe

 

[Audioguru]

The datasheet of the CD2003 AM/FM radio IC is written in Chinese only. Its schematic shows a very simple and cheap radio circuit.
Its performance will probably be awful.

 

[godfreyl]

The datasheet of the CD2003 AM/FM radio IC is written in Chinese only.

Her's a datasheet in English: https://www.ak-modul-bus.de/cat/documentation/CD2003.pdf

Its performance will probably be awful.

That's a bit negative. Some people want a $500 tuner, others want a $5 portable radio.

 

[Audioguru]

That's a bit negative. Some people want a $500 tuner, others want a $5 portable radio.

Thank-you for the English datasheet.
Maybe you have not tried this $1.00 "radio" from The Dollar Store. It comes with headphones and a battery so the "radio" part is free.
I got two for subscribing to a newspaper.

It gets overloaded by strong local stations and has poor sensitivity for not so strong stations. Its selectivity is poor so it is very difficult to change stations. Its sound is distorted. It is noisy. IT IS NEGATIVE!

I bought two clock radios for $1.75 each on sale. The radio part is the same as above but the clock part is excellent.

I still have the General Electric clock radio that I won at work in 1972. It has many transistors and IF transformers and performs pretty well. I replaced its power amplifier and speaker with better newer ones and added bass boost. It still works and is used but its LED display has dimmed a lot in its 43 years. It is playing now.

 

[keith1200rs]

I cannot see the purpose of describing how bad your purchases are.

I haven't used the CD2003 but I have worked with the TDA7088 and the Chinese copies of it and the radios can be quite acceptable in normal use. They aren't communications quality but then I seem to recall I could buy complete radios based on the chip with headphones, batteries and instructions for $0.39. There is nothing wrong with working on a design with them. They can form the basis of many useful products.

As already stated - try to arrange your components to minimise track lengths.

Keith

 

[Audioguru]

I cannot see the purpose of describing how bad your purchases are.

Cheap junk has the poor performance that I described.

I also won a Sony Walkman stereo portable earphones radio at work. It has a local-distant switch to attenuate its antenna so that strong local stations do not overload it and appear all across its dial. Of course when it is in the local position then its sensitivity to weaker stations is awful. Here there are many strong local stations so the weaker ones are not received.
My not too expensive hi-fi tuner and the radio in my car work perfectly. Very sensitive, no overloading, good selectivity, low noise and low distortion.

My first hi-fi tuner was a fairly cheap kit. It performed very well.

 

[keith1200rs]

And how does that answer the questions of the original poster?

Keith

 

[Audioguru]

The original poster might live in a country without any radio stations. He is learning how to layout a pcb for a high frequency circuit he might never build.

 

[wzhe6095]

Thank u for the English datasheet and discussion. I have changed my board a little and corroded it with FeCl3 yesterday. Now it works well by strong station, but there will be some noise at weak station. I bought complete components within $1.

 

[Borber]

Antenna is the essential part of a receiver.

 

[fredd]

Avoid the jumper wire.