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FM RECEIVER - simple diagram needed

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ighani

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FM RECEIVER

A.O.A my new project in communication systems is "fm receiver" . I need a simple circuit diagram for this . thanks
 

You can buy a very simple FM receiver at The Dollar Store for only $1.00. Because it is so cheap then its performance is horrible.

You can make your own FM radio if you can buy the special parts somewhere and borrow the expensive test equipment to align it.

An FM radio that performs well is very complicated, not simple.
 

u can try to search for the diagram by using this engineering projects search engine.

**broken link removed**
 

Your intention isn't clear. Are you looking for a low complexity receiver design? In this case, analyzing the said dollar store
products or possibly a cheap radio from your home would help. Or do you mean a low part count, but rather complex function
single chip receiver?

In my opinion, two building blocks are mandatory for a FM receiver, a frequency selective frontend (most likely involving
some gain) and a FM demodulator. Everything else is optional.
 

I hate to mention a poorly performing single transistor super-regenerative receiver. There are a few of them on the internet. It is really an AM radio but receives FM by "slope-detection" when it is tuned to one side of an FM radio station. They are overloaded by strong local stations easily.
 

There are several companies that make single-chip FM receivers that can be controlled with a serial input. SiLabs is one **broken link removed**
92_1260210308.jpg
 

The tiny SiLabs chips are used in cell phones and are not very good. They are a little better than the garbage Philips chips that the Chinese copy and are sold as a radio for $1.00.
 


Use the TDA7000 it's easy to implement and very good option. I really don't know if it is obsolete, but in my country you can still get it.
 

The TDA7000 was a very poor FM radio. It is not made anymore and is replaced by the TDA7088 that "scans" for changing stations. Its performance is just as bad.
 

Same story talk Audioguru - everything someone suggest he call garbage.
Garbage Man...ha ha
Simpliest solution is one Fet radio which give solid result for such a small device
and of course Silab chip is very good option.
 

Good FM radios have a 10.7MHz IF amplifier with crystal filters. The TDA7000 and TDA7088 have opamp active filters operating at only 70kHz for the IF amplifier.
A huge difference.
 

Hi

please see under link, you will see some simple project for fm receiver :

**broken link removed**

regards
 

Everyone's suggested TDA7000, take a look at TDA7088 as well. Has automatic scanning with switches.
 

I answered but this site did not post my answer.
Thee obsolete TDA7000 and newer TDA7088 "radios" have terrible performance.
 

Hi audioguru,
I have a small pocket radio I bought about a year back. Once I opened it and saw the TDA7088 chip. But the performance of the radio is quite good. Good reception as well as clear audio output. It sounds really good to me. And it's also quite popular over here. Costs about $0.5 - $2. I got mine for $1.5.
 

I think the point Audioguru is making is that in these days of cutting costs to the bone, a lot of quality has been sacrificed just to save a few pennies.

Although the quality of the TDA7000, TDA7088, SC108 and others is reasonably good, they will never match the performance of designs that use properly filtered IF stages and linear discriminators. Those ICs have poor overload characteristics, poor phase response and audio distortion figures many times greater than is achievable with just a few extra components. In other words, the manufacturer has designed them for lowest cost rather than highest quality. Whether that is acceptable is of course a decision to be made by the end user. My own choice would be $5 for a high quality receiver rather than $2 for a poor one.

Brian.
 

o, ok, that's what he meant. I was just stating that the quality is reasonably well. It's acceptable as I get clear output and that's all that matters to me. Although I must say I am really impressed by the radios in the Sony Ericsson and Nokia cell phones.
 

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