Fm receiver schematic tda7000 with continuous scan loop

[dr pepper]

You are aware mason that the white sound from the tda device actually comes from a noise generator within the chip.
White sound on a 'standard' fm receiver doesnt come from the air (except during odd atmospherics) its generated within by the gain stages.

 

[MikeMl]

You are aware mason that the white sound from the tda device actually comes from a noise generator within the chip.
White sound on a 'standard' fm receiver doesnt come from the air (except during odd atmospherics) its generated within by the gain stages.

I tried to tell him that in Post#6, but I don't think he believes us

 

[JimB]

I tried to tell him that in Post#6, but I don't think he believes us

Of course not, he is not listening to you on an un-squelched FM receiver, that is why.

JimB

 

[dr pepper]

Yup.

 

[Mason Burns]

You are aware mason that the white sound from the tda device actually comes from a noise generator within the chip.
White sound on a 'standard' fm receiver doesnt come from the air (except during odd atmospherics) its generated within by the gain stages.

You mean all chips generate their own white noise like the TDA7000 does. I'm a newby to this actually. I'm a database computer programmer, then trained in networking and had training on specific computer and banking equiptment designed and built by the Unisys Corp. I have never done benchwork on electronics except motion, vibration, and ir light sensors for myself. I did have some ac/dc in tech school but I switched to programming so I learned very little although I'm a quick study and grasp quickly, Boy, did I ever wish I had stayed in electronics now. It's just that now, I know what I need and damn it seems just out of reach! Do you know anything about the ATmega16 ATmega32 TEA5767 TDA1308 ISP 5V FM Radio AVR Development Board MCU? It's AVR with a TEA5767 on board. I wonder if you can
control that IC's scanning thru it. Another dream of mine, 200ms at 1 Hz jumps!!!!LOL

Guys, I'm not insane.....I have audio proof of all the reasons I'm searching for this FM miracle!!!!!

 

[Mason Burns]

Of course not, he is not listening to you on an un-squelched FM receiver, that is why.

JimB

Squelching, the noise I desire to hear? Please educate me!! Or was that intended in another manner?

 

[audioguru]

You mean all chips generate their own white noise like the TDA7000 does.

A normal FM radio has very high RF gain. Then it amplifies its own noise when there is no station being tuned.
A TDA7000 radio IC uses a Mickey Mouse circuit that generates spurious sounds (not just white noise) between stations so it mutes those sounds and inserts a normal-sounding white noise generator.

 

[JimB]

Squelching, the noise I desire to hear? Please educate me!!

On a radio which is intended to monitor a frequency which is unoccupied most of the time, there is a circuit called a "squelch circuit".
The squelch circuit silences the audio output from the receiver in the absence of an RF signal from the antenna on the frequency to which the radio is tuned.
It it there to stop the noise from getting on everyones nerves.

So, an un-squelched FM receiver would be one which is just listening to the noise.

Or was that intended in another manner?

The whole tone of my post was to back up MikeMLs comment and that you were not listening to sensible advice from forum members simply because that advice did not arrive via the medium of "Raudive voices".

JimB