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Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809 -
Re: Bypass caps articles and learning
The two most useful take-aways from the linked article are that ceramic dielectrics such as Y5V (used in the article) and Z5U have two nasty characteristics you must be aware of before using such parts. From the article:
I initially chose Y5V dielectric for the 2.2uF ceramic alternative, on the basis that temperature and voltage performance weren't likely to be significant, while small size and low cost was. But when you dial in the voltage across the capacitor you find that at 31% of rated voltage - 5V used on a 16V part - the capacitance is down to one quarter of the rated value! In other words, my chosen Y5V 2.2uF part was only a 0.55uF capacitor.If you use a Y5V part much above 40C and at as low as 50% of its rated DC voltage, the true capacitance in the circuit could be as low as 10% of its nominal rating. If the true value matters, use X7R (or X8R) with a voltage rating 8X-10X the circuit DC voltage or use CGO (NPO). With CGO, the capacitance change with temperature and DC voltage is negligible.If you are using Y5V capacitors with DC bias across them - as you always do in a supply decoupling application - carefully calculate the effective capacitance value. You could be 'out' by enough to seriously impair circuit performance and reliability.
Personally, I know large form-factor surface-mount monolithic ceramic capacitors are evil, but a necessary evil. Seriously, the things crack and short fairly readily if there is a temperature gradient end-to-end when soldered onto a board or the PCB flexes too much. Flexible termination types reduce that significantly. But they're still evil.PeteS in CA
Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells.
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To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it.
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Re: Bypass caps articles and learning
Thanks for articles like this. I have a BSEE but don't actually engineer anything. I work as an avionics technician. It is nice to read stuff to keep the education going.Comment
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Re: Bypass caps articles and learning
edn.com has so many good information and great for expanding the knowledge.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: Bypass caps articles and learning
Input cap for SMPS:
http://www.eetimes.com/design/power-...+EETimes+DailyLast edited by budm; 05-02-2013, 12:31 PM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Hello!
I have two projects on my work bench. One is a friends dead JBL Xtreme speaker with a blown voltage regulator and corresponding bulged and shorted cap. That cap has clear markings so I know what replacement I need for it.
The other project however is a whole different deal. It's a Zoom 9000 guitar effect from the 90th that has developed a devil hound howl when there is no input from the guitar. I'm guessing caps problem. So, since I don't really use this effect anymore I thought it would be a perfect project to learn on.
I have studied the board and... -
I'm trying to repair two old VCRs, they both have bad caps. One has leaky ones, the other would barely run until I subbed in some caps from another power supply I had laying around (though they are the wrong values). This vcr works for an hour or two, but then the power supply starts whining and the picture gets lines in it. I didn't replace all the secondary caps, so another voltage might still be problematic, or the values I used are too far off.
I've been on mouser and digikey but the options are a bit overwhelming. I just need some new ones that will work. They don't need to be top quality,... -
Good evening
I recently aquired a rev 1.1 Gigabyte 60XT, and was suprised of the amount of leaking caps for a motherboard of the P3 era. Especially the way the 330µf caps seems like the housing discolored even.
Now, there are some 3300µF 6.3V KZG series around the CPU. Would it be OK to replace them with something like EEUFR1A332 ? (Panasonic FR 3300µF 10V). Or was this board designed around very low ESR caps?
But I was also suprised about the bigger boys, which are 330µF 25V.
Could it be they used 25V caps because they were cheaper / available at that time?... -
I did it again – I had to fulfill my inner desire to fix yet another old piece of hardware. This one is actually kind of worthwhile, too – it’s an EVGA e-GeForce 7600 GS AGP video card, model P/N: 256-A8-N542-T2. With the popularity of “retro” PCs from the Win9x to XP era going up, and the diminishing supply of decent AGP cards, it is expected their prices will go up. Or is it? I bought the this video card rather on the cheap side (~$9 USD shipped to my door), because the eBay seller listed it for parts or repair (and correctly noted the bad capacitors.)
So, here is the... -
Good day!
I have a Samson Resolv studio monitor that has no sound output. I've opened it up and found two caps that are bulging on what I believe to be the power supply section of the amplifier board. The board is marked Resolv 65A AMP V1.2. The caps in question are YUSCON, 2200uF, 35V, 85C temp and have markings of RA(P) and are 16mm x 25.5mm tall. I've attached the schematic and the caps in question are C5 and C6. I'm assuming they are low esr caps. I've tested both caps and they test low uF, nowhere near 2200uF.
I'm going to replace the caps and I'll be the first...
Comment