Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

FM RECEIVER - simple diagram needed

Status
Not open for further replies.

ighani

Newbie level 3
Joined
Dec 6, 2009
Messages
4
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Location
pakistan
Activity points
1,317
FM RECEIVER

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

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498
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.
 

adamltc

Newbie level 3
Joined
Dec 7, 2009
Messages
4
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Location
SG
Activity points
1,297
u can try to search for the diagram by using this engineering projects search engine.

www.mylab.tk
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
49,159
Helped
14,391
Reputation
29,046
Reaction score
13,143
Trophy points
1,393
Location
Bochum, Germany
Activity points
283,318
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.
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498
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.
 

GSM Man

Banned
Joined
Apr 15, 2009
Messages
671
Helped
168
Reputation
338
Reaction score
94
Trophy points
1,308
Location
New Jersey, USA
Activity points
0
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
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498
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.
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498

penrico

Full Member level 5
Joined
Aug 28, 2001
Messages
286
Helped
27
Reputation
54
Reaction score
8
Trophy points
1,298
Location
Argentina
Activity points
2,393
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.
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498
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.
 

zlatkoMM

Full Member level 5
Joined
Apr 4, 2008
Messages
296
Helped
13
Reputation
26
Reaction score
7
Trophy points
1,298
Location
Croatia
Activity points
2,884
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.
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498
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.
 

Audioguru

Advanced Member level 5
Joined
Jan 19, 2008
Messages
9,293
Helped
2,143
Reputation
4,280
Reaction score
1,968
Trophy points
1,393
Location
Toronto area of Canada
Activity points
58,498
I answered but this site did not post my answer.
Thee obsolete TDA7000 and newer TDA7088 "radios" have terrible performance.
 

Tahmid

Advanced Member level 5
Joined
Jun 17, 2008
Messages
4,758
Helped
1,792
Reputation
3,576
Reaction score
1,651
Trophy points
1,393
Location
Silicon Valley, California, USA (from Dhaka, Bangl
Activity points
30,543
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.
 

betwixt

Super Moderator
Staff member
Joined
Jul 4, 2009
Messages
15,216
Helped
4,958
Reputation
9,938
Reaction score
4,783
Trophy points
1,393
Location
Aberdyfi, West Wales, UK
Activity points
129,201
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.
 

Tahmid

Advanced Member level 5
Joined
Jun 17, 2008
Messages
4,758
Helped
1,792
Reputation
3,576
Reaction score
1,651
Trophy points
1,393
Location
Silicon Valley, California, USA (from Dhaka, Bangl
Activity points
30,543
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.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top