FM receiver with TDA7000

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cybergrisu
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FM receiver with TDA7000

Post by cybergrisu »

I tried to build a FM Reveiver according to the given schematic (http://www.pcs-electronics.com/schematics/Tda7000Rx.jpg).
The frequency adjustment doesnt work and i think i know why:
It seems that the whole oscillating circuit is wrong. The 22k potentiometer is between the +5V and 0V and the output only goes to a 1uF Capacitor. So it doesnt have something to do with the frequency....

Am i right?

My solution was a redesign of this part: the output of the potentiometer goes between the varicap diode and the 10nF Capacitor. I also connected the whole ocillation circuit to +5V instead of 0V.
If somebody wants to see my solution, please tell me and i make a scan.

Christian
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pcs
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Post by pcs »

You're right. Had a look at the jpg and its not right.

Can you make a scan with your corrected solution?
I will update the pic on the website.

Thanks for pointing this out, missed this error.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
cybergrisu
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Corrected Schematic

Post by cybergrisu »

Hi!

No problem...
Here is the the corrected schematic, which works great for me:

Image

Christian
samadica
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Post by samadica »

I wanna build a fm reciver by TDA7000, but i want to simulate it with a software,how i can do that?can i do that with orcad?
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pcs
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Post by pcs »

You need spice model first for tda7000 and I don't think you'll get one.

In short, forget about simulating a complex IC like this.

Start by simulating simple circuits.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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