17.10.2008
There are a lot of ready-made projects in the network with clocks, and on PICs, and on AVRs, with various indicators. At the time of creating this page, I had a TDA8425 + ATMega8 tone control installed in my homemade CD player. There were several reasons for replacing 8425 with 7313, the main one - 7313 sounded slightly better (as it seemed to me), and besides this, 7313 has several advantages.

A few words about the design: an analog grounding shield is made on the side where radio elements are installed. Through jumpers, it is connected to analog ground on the opposite side. The inputs are signaled with respect to analog ground. It is removed in the same way - relative to the analog ground. Mega8 fuses are set to internal quartz 8MHz, BOD level is set to 4V. Analog and digital grounds are separated. If it is not possible to use different feeders, then the earths can be combined at one point (preferably closer to the shielding winding of the power transformer).

27.10.2008 last update
There is no menu. Only direct commands from the IR remote control are executed (RC5): 
- volume +/- 
- bass +/-14дб 
- treble +/-14дб
- mute Rare 
- mute Front 
- mute All 
- input select (1, 2, 3)

pcb

Top Layer

Bottom

Menu

Menu

Menu

23.04.2017
Simple tone control.
Button control only.
No IR is used.
Only three adjustments are made: +/-bass, +/-treble, +/-volume.
Loudness is always on.
The signal is fed to inputs No. 3. We take the signal output from the front output.
You can connect an indicator that will display the adjustments made.

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Photoresist

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First power up