FM receiver schematic TDA7000 continues scan loop

[brickman7]

New to electronics design, computer tech needs a schematic based on the simple TDA7000 ic to continuously scan through the frequenuency! I have the TDA7000s, and YDA9088s but they are surface mounts. I can get most older ICs from a supplier in China so I'll take suggestions. I just need it as simple as possible. I have TDA2822s for amps, but I can get what is needed.

I just need an fm scanner to scan thru the frequencies and not lock on a station without having to be reset to continue scanning. And output thru an earphone and speaker. Also, I do not want to mute the scanning process.

Thanks!

 

[jiripolivka]

So you need a sawtooth or triangle voltage generator which will sweep the FM band by applying the voltage to the tuning varicaps. Any FM radio can be modified this way. Use the opams to generate the sawtooth with a minimum voltage 3 V approx and 30 V maximum, try the repetition frequency of 5...10 Hz.