I'm new, so please don't be too hard on me. I already got some experience with Arduino and coding in C (not very good, I might add), did the basic tutorials and now was thinking about my own first project. I'm not quite familiar with all the accessories out there, so maybe you could give me a push in the right direction.
I have an old record player laying around and wanted to use an arduino uno to control the tone arm with servos (not while playing, just to strat and stop). This part, I guess, I can handle.
My second idea is to scan the surface of the record and detect the pauses, so I can use that information to set the tone arm at the start of any desired track or maybe skipping tracks.
The fact, that vinyls are black and there is not much contrast maybe difficult to handle. A barcode scanner could work. Maybe an optical sensor driving from the outside to the inside and logging the surface reflection...
So if anyone of you got a decent idea I'd appreciate your anser.
I just got a Johnny Cash CD collection from local library - the discs were all black! Played just fine.
The spaces between tracks on a record are smooth, yes? Vs a V groove where the music actually is.
The flat space will reflect a light (laser) pointer, while the V groove will deflect it.
So you could make a pointer/sensor with a narrow beam and look for reflected light back.
Trouble is keeping it really light so as not to press the needle into the track, and pay attention to the tone arm balance.
@robtillaart: This really looks quite interesting. This shows at least it's possible. Although I probably won't go as far to scan the whole record But it sure would be interessting to hear the quality they can accomplish.
@CrossRoads: Now that you mention it i remember that the old Playstation disks where black on the backside as well. But I'm probably not goint to use something as powerful as a CD/DVD laser to read the surface. I'll see if I can get a hand on an old laserpointer. Then i still have to find a proper detector though.
The weight should not be a problem, as the tone arm has counterweights to ballance is out. While scanning one of the servos could support it. Another approach could be to install an extra arm just for scanning.
If you don't scan the entire record, how will you know where are the pauses? If you look only at the place where the needle is at that point, you get no useful information.
@Shpaget: Of course you have to scan the whole record to get a decent information. Either you scan a line with a linear sensor like a barcodescanner or the linear camera Grumpy_Mike suggested or you could ta a selectiv sensor on a carriage scanning the record from outside to inside, thus creating a surface profile.
@Grumpy_Mike: This looks very promissing. although the resolution of the camera you posted should be to low. At a scanning width of ca. 80mm and 102 pixels resolution, one pixel only represents about 0.78 mm. Pauses on records are not that long. Do you know any other name for that kind of camera? I can't find any aside frome the one you already posted.
(sorry of my interpunctuation. My sentences look horrible)
I see, there are some CCD Array sensors out there. Most of them out of my price range. The cheapest way to get one would be by taking appart an old fax device. But I think creating an interface would excel my abilities.
I will probably experiment with the laserpointer/photoresistor version and come back to this if I can't get it to work. So far I experienced a noticeable difference in resistance when the beam is deflected by either the dull or shiny surfaces of the record. But the beam probably has to be focused or masked to make the laser point even smaler.
I'll let you know if I make any progress. Thanks so far!
But it sure would be interessting to hear the quality they can accomplish.