UP or DOWN steps 1 or 9 kHz, STEP+UP or STEP+DOWN steps faster

use STEP button, to select 1 or  9 kHz steps.

lcd must be 2 lines, 16 characters, HD44780 compatible.

option to put your own text on second line of the lcd

[ 1 ] press UP and DOWN while powering up.

[ 2 ] use UP or DOWN to select a character.

[ 3 ] press STEP for the next character.

repeat [ 2 ] and [ 3 ] until the line is full

data is saved, and displayed on the 2nd line.

Uses 3 digital outputs for output-filter switching.

Range 1 = 512 -> 800 kHz. ( out1 = 5 Volt )

Range 2 = 800 -> 1200 kHz. ( out2 = 5 Volt )

Range 3 = 1200 -> 1800 kHz. ( out3 = 5 Volt )