Luxman LV 105U Phase 1: Power Supplies
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- เผยแพร่เมื่อ 1 ต.ค. 2024
- Power supplies are the heart of any electronic system. In this video I go through the various power supplies in the amplifier, replace missing parts and verify operation. It's gonna be a while before this thing puts out any music!
#amplifierrepair #electronic #audio #electronicrepair #vintageaudio #electronic
Another superb vid, thanks Ray. Your explanations are soclear it makes watching this an absolute pleasure. Such an interesting project. Great stuff.
Thanks Peter! I value comments like yours, because I'm never sure that I'm making things clear.
This project will be interesting for sure. Please stand by with a straightjacket in case it pushes me over the edge! 😝
Hi Ray, I sizzle like hell when I see PCB traces cut - I hate it. If I find a PCB that has been blackened by heat like this, I do three things, depending on the condition and possibilities of the given board: 1) I measure the conductivity of the burned area 2) I mill the individual paths between them and create an air gap. 3) I completely remove the burned area and replace it with a new piece. A PCB burned to black in this way can be conductive due to charring, and in addition, the conductivity changes depending on the air humidity and further burning of the damaged area - personal experience.
You're not the only one who couldn't fit the cooler, when I modified the Yamaha power supply last week to power the BT module, I also couldn't fit the added cooler, unfortunately I only found out at the very end during assembly. I chose the height according to the neighboring cooler and I didn't think it could be a problem, later it turned out to be quite a major problem because the added cooler hit the DVD drive holder. Disassemble everything again, remove the cooler, lower the height and put everything back = about an hour of extra work - sometimes we have to think in 3D when upgrading.
Nice day 🙂 Tom
Tom, in agreement about burned circuit boards. But these are discolored from heat, not charred like is often the case when tube amps short.
And yes, I despise the practice of cutting PCB traces. Especially in an amp like this, where pulling a few connectors would have done it.
Good stuff, Ray. Thanks! Don't sweat the wrong footprint. We all make that mistake, even when we check closely for that very thing. It is best to have a second set of eyes look things over. And, print the board on paper and line up every component, before placing the order. Caution = InkJet printers are known to not print 100%, even when set accordingly. The work-around is to place a 100mm scale line on the board drawing on the comment layer, include the comment layer when you make the print, and measure the scale line to make sure the print size is absolutely true. My InkJet prints a 100mm line as 98mm. So, I have to run my InkJet at 102% (custom setting, not "full scale.") HTH.
Wow, that is really good advice! Thanks for posting this. The software lays the board in a grid, which is how I got the spacing right between sockets. But printing it out is smart; I will do that in the future.
I just got the second set of boards, and it looks like they are going to work. At this point with this unit, this may be the least of my problems!
Hi Ray! Nice to see you so quickly with the rest of the work! Happy to see you in a fine morning in India! Enjoyed !Great!
Thanks! It's going to be a challenge, but that's not a bad thing.
India is a bit of a new fascination for me. I went to a wedding earlier this year, and a young man wed his college girlfriend, who's from India. Her family attended. After the wedding, I was on Wikipedia looking up the bindi, and 2 hours later I was still going down the rabbit hole.
It became a place I'd like to see before I shuffle off this mortal coil. 🙂
I do the same thing with that lead kinked.
Excelent vid Ray. I have learned a lot with you. Thank you.
Thank you, Fernando. That's the best compliment I can get, because passing on what had been passed on to me is the whole purpose of this channel.
I can see the day we will have to solder wires on SMDs to replace on our through hole components
People are already having small boards fabricated to mount SMD to adapt them for through hole applications.
SMD and microsoldering are the next frontier for me. I'm a big fan of Louis Rossmann, who not only taught himself microsoldering, but figured out how to repair Apple products with zero support from them.
Great work ! Nice try with the board but much fatter traces and you might as well put a ground copper pour on both sides as its better for the planet, the more copper still on your PCB the less is dissolved in an etchant tank somewhere. I used to make a 1to1 paper print of my PCBs and fit stuff and put the board in place and you would catch stuff like a tube socket because when your working with CAD sometimes you forget the scale ! Looking forward to the next part......cheers !
Anyd, the next part may show me being hauled off to a rubber room. This one is going to be a battle right to the end!
Ha !@@raygianelli3612
Hi Ray, can you share what brand/model visor you're using? I do not trust Amazon's Choice anymore :)
Hi Murat! It's an old Optivisor. I just tried to remember how old, and it made me feel old. 😁
I bought it at a hamfest in Miami around 1990.
@@raygianelli3612 thanks and sorry I made you felt old ;)
@@meraydin1 You didn't make me feel old. Being older is making me feel old. 😁
LOL!@@raygianelli3612
May we please know the common name/make/model/price/link, for the lead crimping tool? Thanks.
Where in the video does this tool appear?
@@raygianelli3612 At 26:48. Blue handles. For "putting kinks" in resistor pins. I kink my resistors, sometimes, too. But, I use a different tool and it doesn't do a great job. Speaking of tool tips,,, The hand tools that jewelry makers use to bend wire are very useful on the EE bench... No need to buy the expensive ones. They even have them in the craft section at Walmart. Wow, you're up in the middle of the night, too?
@@raygianelli3612 He probably meant pliers for making locks by bending wire leads.
@@Edisson. Thanks, Edisson. Yes, they are at time mark 26:48, in the video. I am still very much interested to know the details. Thanks!
I found them. No need to look. Thanks anyway.