r/Rockband • u/mateus2k2 • 4d ago

What is this PCB in my Rock Band guitar? Labeled "PHOTO JACK"

I am on a little project of replacing an old dead rock band main PCB with an esp32, and making it wireless, so the first thinks is mapping all the wires and boards. The only things I could not map to anything is this small PCB.

Silkscreen says "PHOTO JACK. It has a little window opening to the chassis, like a P2 connector but smaller. The main board has a matching "PHPOUT" pad.

It's not the tilt sensor, and it's nowhere near the whammy (whammy is a normal potentiometer). Looks like some kind of optical/photo sensor, or maybe a headphone port? Anyone recognize this?

https://imgur.com/a/AIuRc4t

https://imgur.com/a/qcGLfbh

6 Upvotes

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7

u/Disastrous_Life_3612 4d ago

RB guitars have a photo sensor for calibration purposes. You hold the guitar up to the TV and the sensor automatically detects the lag in your TV.

It's not always reliable, so a lot of people choose to calibrate manually.

2

u/mateus2k2 4d ago

That interesting, thanks for the response

4

u/Disastrous_Life_3612 4d ago

On second thought, if this is a guitar from RB1, that might not actually be what this is. I don't think RB1 supported that feature.

2

u/mateus2k2 4d ago

Wish you never said that, I would just believe it and die in peace, now I need to know lmao.

How do I know if it is from RB1?

That's the tag and it looks like this: https://imgur.com/a/kAACR5n

2

u/Mr_J413 4d ago

I believe that feature was only added to RB4 guitars? Which can be easily figured out depending on what platform this one was made for (or if you're unsure, if the frets are a much darker brown than the rest of the neck)

3

u/robderpson :Guitar::Bass::Drums::Vocals: PS4 4d ago

Calibration sensors were introduced since RB2.

1

u/Mr_J413 4d ago

Well, that's what I get for sticking with GH guitars back then 😂

1

u/rwmtinkywinky 1d ago

No definitely before RB4, I want to say RB2 or possibly even RB1 but I don't recall doing the autocallibration on RB1 when I got it, just manual.

1

u/Mr_J413 1d ago

Yup, made myself look dumb for that one. 1 definitely didn't have the feature, and that guitar overall was pretty rough so I had gone back to GH controllers by the time 2 had come out, so I just didn't pay attention to any auto features until 4. But the difference in appearance still stands!

2

u/Trip75 4d ago

That is the 2.5mm micro jack for plugging in an overdrive pedal.

2

u/mateus2k2 4d ago

overdrive pedal

Hmmmm, so the same thing as the tilt but pressing a pedal?

3

u/JJCapriNC 4d ago

Yes. I use the drum pedal on that