Yamaha CR-620 Lamp Circuit

Anyone familiar with the lamp circuit on this model? I have a service manual from Hifi Engine but cannot read the schematic clearly. What I've read online is that the circuit is it 12 volts but some say AC, some say DC. Some say all series, some say series/parallel. I wish to replace the burnt out lamps with LEDs. Thanks for looking.

 

Bump...

 

Two sets of two lamps in series run off 24V DC supply. There is an irrelevant no-connection wire terminal on the circuit board, simply used to join them in series.

Two of the three meter bulbs are in series together. The tuner needle bulb along with one meter bulb are in series.

So: you'll have to replace the correct two at a time; all four together (using identical "12v LED bulbs" that include regulation); or better, use the 24 volt supply to rewire four or more LEDs in series along with an appropriate current-limiting resistor.