Tunable IF with TDA7000

	Connections to the board
	A better view of the board

This circuit has 'suffered' a lot of modifications over its long life... Even the lettering on the integrated circuit was partially erased of the years.

The main motive of the mods was not that the circuit didn't work right, but were several tries to add some kind of frequency indicator to the receiver. The left RCA plug and associated components are witnesses to the last version, adding a FET buffer amplifiera and taking signal from the oscillator coil.

None of the indicator systems was satisfactory, and the actual stability of the receiver oscillator was so good that it wasn't really necessary either. A simple system with a preset resistor for each of the the desired satellites was more than enough, a simple selector switch to select the channel.

The schematic diagram

The diagram of the TDA7000 IF. It's also available in PDF format for those who can't see PNG images yet. I've also posted the TDA7000 datasheet, for which I had several requests.

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