REVISIT - BUSH Boombox Transistor and Laser Replacement

Hi, this 'revisit' video shows me fitting the laser and a SMD transistor to the pink Bush Boombox that featured in the previous 'trying to fix' video.
Remember that this is just for entertainment and I am not an expert in these repairs. The processes in the video may not be the best way, the correct way or the safest way to fix these things.
I do love fault finding and trying to fix broken things so I hope that comes across in this 'Trying to FIX' series.
Many thanks, Vince.

[gregboren]

Vince, I’ve watched the whole two hours worth of this fix and I must say I am thoroughly impressed. To be honest the first one or two of your Utube’s you did not fix the item. Then I watched the R2-D2 which was awesome and now this one and I’m going to watch all of them now. Thank you so much for doing these. I can only imagine how hard they are to do. Thanks again.

[davidsmith-ihkk]

Vince you are becoming an expert at removing components and replacing them your videos have become more and more complex it is a pleasure to watch you work and by the way I don't care how you pronounce kilo killer or your h es it's just a pleasure to watch you work

[lubomirrolko]

I've replaced several lasers. The PS1, PS2, Xbox 360, all had solder drop protection. So I knew there was a problem. I also knew that your attentive eye would not miss this fact. Super work.

[RussianAigio]

Good morning Vince, woooow, cool 😎 in depth understanding of laser lens, i remember that when I was just a little kid and disassembling everything to see how things work and how they were assembled well before I learn how to fix things, from mechanical to electrical and later electronics, born june 22th 1986 soviet union products and later china came out with everything so yeah .... Man you not only entertain teaching and exploring things fixing them but also often bringing memories with your content Vince .. Thank you 😊

[mrbussey]

Fantastic fixes Vince! Had no idea about the blob you have to unsolder! I would have thought that was something to change the laser settings between different devices. If you should encounter something like this again, I would also suggest testing the headphone port and blue tooth to see if either of them had sound or could be causing problems since when you use either of these it will cut sound to the speakers. Great detective work on that transistor though!! Keep it up!!!

Just an opinion, your video length is not a problem! You keep the flow moving fine! Some fix-it videos I have watched seem to FF past the troubleshooting and slow it down on the less interesting parts. Your videos are perfect, even when over an hour!

[skonkfactory]

Laserdiodes are almost always shipped with their anode shorted to the cathode- it only takes a few nanoseconds of overcurrent to permanently destroy them or damage them. They're way more sensitive than almost anything else you can imagine. There are even special overvoltage protection devices called Lasorbs that you can put in circuit to protect them. Tweaking the diode current pot is also a good way to hurt them!

In the case of your optical pickup unit there, yep, they put that shorting blob on the PCB to stop static from the package from zapping the diode.

[ryansteve]

Thanks for doing the revisit! Learned so much

[Tokaisho]

This was fascinating Vince, I loved this repair and learned so much about the lasers, I loved how you operated the coils with your power supply, thank you for the great video!

[mikejones]

This is correct, all new lasers have a short to protect from static damage. Once removed laser will function normally.

[skonkfactory]

The light sensor that lives underneath the lens actually contains a bunch of different photodiodes- when the beam bouncing back from the disc is off to one side, the pickup control circuit- the tracking servo, to give it its technical name- puts current through the side-to-side coils to push the "spot" on the sensor back to the middle. There's a similar thing where the size of the "spot" on the sensor controls the up-and-down motion of the lens. The focus servo only controls up-and-down, and the tracking servo only controls towards-the-hub vs away-from-the-hub. There's a third servo circuit that controls the speed of the spindle from the frequency of the detected digital signal.

It's really quite neat how cheap they've managed to make them.

[nzjvx]

i never knew about that solder blob i got a faulty numark cd mix unit thats only reading on 1 side. ive ordered 2 laser assembly's one from china that took a month to get here after the first didnt work. i have swapped the boards around cables everything. and all along it was that blooming blob. glad i watched now blimey.

[phaultypmm]

That was great. Detective work at its finest

[Evaldas]

God bless your heart, Vince. I absolutely love your videos.

[geertvanpee]

What a nice revisit Vince! I am really glad you did a video on replacing that laser. And apart from the fix itself, do you know what I like about your videos? You do not simply say like: "Oh well, the laser is faulty, I will replace it and it's fixed." You also try and show how things work as much as possible and you show it while learning yourself, that is really great. Because now after watching your video,  I call myself of course not a laser expert, but I now have a little notion on how they work and what they are about. Thanks for that Vince!

[wasserman]

Hi Vince congrats i am watching you now for over a year or so and you came long way i pull my head and whats more important you are not affraid to make mistakes. As a wiseman once said we are not learning true our succeses ut thrue our mistakes. Best reguards Dipl. Ing Elektr. Axel J. Brinkmann

[skonkfactory]

The reason the laserdiode has three terminals is because there's actually not just a laserdiode in the package- there's also a photodiode that's used by the laser drive circuit to measure how much light the laser is producing, so it can accurately regulate how bright its output is. A laser diode is actually a long, thin piece of III-V semiconductor (usually something like gallium arsenide or gallium indium nitride) with two end facets cut so that they act like mirrors. One of them is almost a perfect mirror (it's the back) and the other is semi-reflective, so it acts as the output coupler. The little photodiode that's used to stabilize the laser power usually sits just behind the back 'mirror', or else it just sits off-axis near the output coupler facet of the laserdiode die.

[rush_hour]

Vince you seem to be under the impression that we want shorter videos. i cant speak for everyone but i love your long videos really interesting to watch and learn. and they are really entertaining. one of the reasons i don't like TronicsFix videos is because everything is just in fast forward almost constantly. its just boring to watch in my opinion. love how far you've progressed though time. hopefully next step is learning how to reball chips.

[Afatt]

That is anti-static solder point, to prevent static on the laser. Ps2 laser replacement also got this, need to unsolder for it to work.

[mohamedbenkhadra]

hey mr.VINCE i really like your content and i just wanted to ask why you are not involving with laptops they are really enjoyable .
i am really enjoying my time when i am fixing my laptops . thank you

[nightstah]

You have to do the same thing with a Wii laser (desolder the ball, which yes is an anti-static measure; I'm surprised you didn't know that). Good vid :)