These two sections of code are between line 530 and 550 and have two changes to slow down how fast it runs through the band when the knob is at the extreme ends. And steps by 5khz instead of 10khz so you don't miss anything.
The first two lines to change in both sections are "delay(250);" I changed it from 200 to 250 to slow it down. Some people might like a delay of 300 miliseconds better with the addition of 5khz steps.
The next two lines to change are "baseTune = baseTune - 5000l;" I changed it from 10000I to 5000I to make it scan by 5khz instead of 10khz. And that is a capital i at the end of the number. Just change the 10 to 5 and save it under a name like "Radiono2". Be sure to keep your original sketch safe so you can restore it if you don't like it.
? // the knob is fully on the low end, move down by 10 Khz and wait for 200 msec
?if (knob < 10 && frequency > LOWEST_FREQ) {
? ? ? baseTune = baseTune - 5000l;
? ? ? frequency = baseTune;
? ? ? updateDisplay();
? ? ? setFrequency(frequency);
? ? ? delay(250);
? }?
? ? // the knob is full on the high end, move up by 10 Khz and wait for 200 msec
? else if (knob > 1010 && frequency < HIGHEST_FREQ) {
? ? ?baseTune = baseTune + 5000l;?
? ? ?frequency = baseTune + 50000l;
? ? ?setFrequency(frequency);
? ? ?updateDisplay();
? ? ?delay(250);
? }
