REVISIT - Catch Up - PART 1

Hi, this video is a catch up on some recent 'trying to fix' videos. These videos don't warrant their own video so every now and then I will group them together and release a catch up video.
Thanks, Vince :-)

[StezStixFix]

Hi Vince. The Line Out is the right way to go on the CD player as it is unamplified - the headphone out is amplified, which is why you could lower the volume and lose the distortion. The problem will be with the wiring, you need a DIN connector for your B&O. 5 pin DIN to 3.5mm would probably do the trick for that setup.

[faithless]

Hi Vince! When revisiting the B&O tape recorder, you presented a ‘fix’ for the recording level, by turning the headphone output. This is NOT the problem. You are using the microphone input to make a recording, for a line level device, such as a discman. Every microphone input uses a pre-amp. Like you would find on a turntable or phono input (they use pre-amps as wel). But when using a line level device, the pre amp of the mic input wil amplifie the signal too much, since it’s allready a high level output. You NEED to connect your discman to the other pins of the amplifier connector. The pins you haven’t used in your previous video, are actually left and right inputs! A DIN connector has 5 connections. One ground, left and right output, and left and right input. And also turn of the mic switch when making a recording via those inputs.

Greetings! 🙂

[dom]

Hi Vince, Great Vid, glad you made some progress with these things. In regard to the MSI laptop and to answer your question about the constant current draw, don't let power supply terminology fool you it's not that complicated once you've wrapped your head around the idea and just simply liken the draw to that of a resistor or even a heater. I also read some of the comments stating that setting the power supply to 5V wasn't an issue as it was a constant current load pulling the voltage down to < 1V and so therefore the chip is "safe" unfortunately this is not the case, current draw would not be instantaneous in this case and the reason people say it "pulled" the voltage down is because that also is not instantaneous, therefore you would be exposing the chip to the volatge set on the supply (5V in this case) until the voltage drops low under the increasing current draw, some bench power supplies are quick enough to show this happening real time by showing CC and the CV display trading places, some of the cheaper ones aren't quick enough to display this and some don't even tell you if your in a constant current state ot a constant voltage state.... if your PSU is in the latter you could connect up your scope to the shorted output and you would see it start at 5V and then after start dropping or decaying until it ultimately drops to the <1V under load that the PSU was showing. In the case of the watch COB, i don't see a reason why putting your meter in diode mode wouldn't also work for testing the LCD segments as there is also minimal voltage present on the probes in this mode (and other modes) and may be more convenient. As for peeling back the cob without damaging the traces on the ceramic, you might try heating the resin/epoxy like material up and using a plastic spudger to peel rather than chip away. Again thanks for the effort in your vids :)

[caliclark]

I love seeing the little updates. So curious on some of the videos

[joshm]

It's so cool to see you learn over the couple of years since the start of this series, also crazy to think that a how-to channel with 100K subscribers would end up being my favorite YouTuber of all time

[MeDicen_Rocha]

Vince, cassette recording crash course:
Its not that you dont want it to hit the red, its that you want it to not _stay_ in the red. Its fine if it peaks from time to time into the red thought but the type of tape determines how much margin you got. Generally for good Type 1s, +2 is fine, maybe +4 in a very good one in a deck thats calibrated for it. Type 2s, specially chrome tapes, you want to keep out of the red zone always. The lower hiss of a chrome will make up for the reduced volume. For Type 4s, some very good ones can go all the way up to +8 without distortion, its really up to the deck if its actually able to go all the way up there. Also for the love of god, ditch the Hi Tech tape and get a few TDK D's or Sony HF's

[stepheng]

The headphone out is a dodge workaround. You were right with the line out just wrong at the din end, you need a din to RCA cable.

[jaredl]

Thanks for the updates! I'm sorry you've given up on the laptop cause I really still have hope for that thing. Perhaps you could get in touch w someone like Adamant IT for some guidance?

[thecaptain]

@My Mate VINCE
What would make that chipset proper center is as follows: First you need to solder up the ball pads on the bottom of the chip and then again on the board. Then apply a very generous amount of no-clean liquid flux to both surfaces and lay the chip down on the board holding it generally and gently in place. Then with a heat-gun, apply heat to the top side of the chip in a circular motion until the solder melts. the chip should then center itself. Let it cool and you should be good to go. The key point is the flux. Flux allows the solder to have proper surface tension and will join the pads on the chip to the pads on board without any of the solder migrating. This process is called "reflowing" and is the same as one would do on a PS3 or Xbox 360. It's a fairly common thing. I watched that last video, you did not do any harm with the voltage you applied.

[coll]

To clarify for the laptop thing in the start. Constant current means that it'll adjust the voltage to maintain the current that you have set on your meter. Since V=I*R if R changes for any reason the device must change voltage to continue to output at the current you have set. This is very useful for charging certain types of batteries. Constant voltage is similar. It'll try to maintain the voltage you set regardless of how R changes. So current will vary to make sure the voltage stays at the setting you specified. For the laptop you set the voltage for you read a specific voltage because there is some short somewhere dragging the voltage down. Like you said if for some reason that short disappeared you could potentially blow up more chips on the board that may use that voltage line. Usually it is not good practice to feed voltage from a source directly into a device because of the inter-connectivity of the chips unless you absolutely know what you are doing. But similarly it can help determine short faults like this as you'll feel heat or be able to find it with an IR camera.

[MikeB_UK]

Vince, thanks for these updates. Your videos are great fun to watch. Please keep them up. I deleted my past comments as I am old and disagreements/arguments stress me out. Fixing things, especially electronics is such a rewarding thing as it invites us to learn more about so many things which is both addictive and fun. All the best.

[MalcolmCrabbe]

Vince, the 5 pin DIN socket on the rear of the tape deck marked AMP will have L/R line in and L/R line out with the centre pin common ground. The levels are typically 1v peak to peak. The Microphone socket will be for levels a lot lower... the problem wasn't so much the line out level from the CD player, it was the fact it was connected to the more sensitive MIC socket. - If you you the LINE out from the CD player and connect it to the LINE in pins of the AMP DIN socket you'll have better fidelity

[dodgydruid]

Wait until you put something like Quadrophenia or most of Pink Floyd through the record deck of the B&O and experience its astonishing quadrophonic sound, Jeff Wayne's War of the Worlds is another must have for old hi fi and seriously cool even though its quite old now. Jean Michael Jarre another awesome old hi fi choice esp the Oxygene compilation as you get to hear the sub and super harmonics which modern stuff misses a bit unless you have super expensive Denon sort of gear (my £10 Denon hifi is epic, still ain't fixed the CD, got the belts but discovered using a 3.5mm male to male lead it plays off my fone or daughters iPad perfectly well but the clarity is astonishing)

[nicwilson]

I honestly believe you shouldn't give up on the laptop yet. I know you're busy as hell and have all sorts of other stuff to fix, but I reckon you're actually getting somewhere :)

[robtitheridge]

hi vince if you use the amo socket on the B&O instead of the mike socket you will be able to use the line output on the CD player and get realy good sound quality.

[TheCodr]

Good video as always, nice to have a few in one to mix things up a little 😃 the laptop i do still think it would be repairable. I'm not sure if you've seen my video on hand reballing but maybe try hand reballing it and putting it back on again? Either that or I probably have a stencil to match that particular ic that you could have

[solidamber]

Hi vince re cassette recorder the recording inputs are the the two spare pins on the socket marked amp, the mic input is for a mic only.
To set levels it should flick into the red occasionally, or the level will be too low.

[berndeckenfels]

Just a side Note, cheap lab bench supplies have a poor constant current limit as they have caps which charge up to the set current, so it’s important for them to not connect the load after you turn it on.

[unimportant]

Constant current is simple, just understand ohm's law: V = I * R (voltage equals current times resistance.) So if you set your power supply to 10V and 3A, for example, and feed the shorted chip that has let's say 0.2 ohms of resistance, then the power supply will have to limit the voltage to 0.6V (3A * 0.2 ohm) to keep the current at 3A. Any higher voltage will allow more current to flow. This is constant current mode (CC) - limiting the voltage on the load in order to limit the current. However, if you now connect a load with 20 ohm's of resistance, for example, then the set 10V is not enough to reach the 3A limit (I = U / R : 10V / 20 ohm = 0.5A). So now the power supply is in constant voltage mode (CV), outputting the set 10V and 0.5A of current will flow.

So yeah, pretty sure you didn't kill the chip. But next time try removing the decoupling capacitors ON the chip package before removing the chip. Those go short sometimes too and are replaceable.

[GadgetUK]

Great update =D I was surprised at that line out thing - I thought you were doing the opposite, using headphone level. Lineout tends to be quite low and often you would feed line level into a tape deck like that.