Electrolytic caps -- lifespan/longevity, new-old-stock, gently used - Page 1
Forum section: electronics / beginners

author: 13hm13
author_rank: Frequent Contributor
timestamp: December 08, 2013, 09:56:52 am
content: I have devices -- such as early 1990s portable CD players (Discman) -- that use electrolytic caps ... and these may be causing various performance and reliability issues -- poor tracking, clicking noise in audio signal -- I've noted in these now-antique devices.These caps are mostly low-voltage Japanese brand -- and WRT to PSU, only see clean/pure DC (battery). Now that does NOT mean they see no frequency (e.g., the XO and noise from the D/A converter, as well as PCM noise from the decoder and laser).GENERALLY speaking, how long do electro caps last if gently used, used very little or even new-old-stock?BTW ... I don't have an LCR or ESR meter to troubleshoot, but may invest in one soon. I can't see any visible signs of trouble (leak, bulges, etc.).Thx!

author: amyk
author_rank: Super Contributor
timestamp: December 08, 2013, 10:26:35 am
content: They will dry out - the seal is not perfect. If you want to reuse NOS then check them with a capacitance meter and reform them first.

author: 13hm13
author_rank: Frequent Contributor
timestamp: December 08, 2013, 11:02:41 am
content: Quote from: wilfred on December 08, 2013, 10:09:15 amYeah ... know about the lube issue with transport (worm drive) ... I re-lubed using stuff similar to OEM grease, but the tracking problem persistsAnd, on another portable CDP, there's a weird electronic cyclical / thumping sound I hear in the audio -- like a playing card in bike spokes.

author: 13hm13
author_rank: Frequent Contributor
timestamp: December 08, 2013, 02:24:17 pm
content: Another thing I've noticed is higher-end PC motherboards claiming better reliability/performance via switching to use of solid caps.Asus:MSI:Gigabyte:Other ("better") PC components -- e.g., PSU's -- also increasingly use solid caps.

author: SeanB
author_rank: Super Contributor
timestamp: December 08, 2013, 03:09:40 pm
content: Thumping is a bad ram, or a dry joint on the one pin of the RAM, the audio processor or a through hole joining the RAM to the processor. Most likely is the RAM though, a single bit error will make that noise. Poor tracking is often a worn laser diode though, it will have a lower power output, and with a worn mechanism and poor tracking it will struggle. Run through the power setup and adjust it. With Sony units those small capacitors are rather infamous for dying, especially the ones under 6V. those really need to be replaced with new ones, buy new stock rather than 20 year old ones, they are likely to last longer.

author: 13hm13
author_rank: Frequent Contributor
timestamp: December 08, 2013, 05:29:09 pm
content: Quote from: SeanB on December 08, 2013, 03:09:40 pmThx ... some things I forgot to note were that although these units are old, they have very few hrs of total powered use (<100, if that). And that was gentle use -- not portably at all, but as firmly placed bedroom unit connected to main stereo or computer speaker system. Not sure a laser diode can wear out in such limited use.

author: SeanB
author_rank: Super Contributor
timestamp: December 08, 2013, 05:51:30 pm
content: They wear out with time only, operating them worsens it. Have you checked the optic are clean, they are dust magnets. My one died from old age only after 5 year, had to get a new KSS210 for it, and currently it has died again, but as I use it as a radio only CD is no longer a worry, that is why I have a PC and some good speakers and a good USB interface.

author: 13hm13
author_rank: Frequent Contributor
timestamp: December 08, 2013, 08:21:23 pm
content: Quote from: SeanB on December 08, 2013, 05:51:30 pmAre you referring to the laser diode? If so, this remark is incorrect. Laser diodes, for optical disc units, don't "worsen". They either work or fail catastrophically (all of a sudden). Like an LED or diode. Also, laser failure is more an issue with high-power devices that are also designs more than 20 years old.

author: nukie
author_rank: Frequent Contributor
timestamp: December 09, 2013, 11:02:42 am
content: Any examples?? The ones I know of has only a few on the output side and not fully equipped.Quote from: 13hm13 on December 08, 2013, 02:24:17 pm

author: 13hm13
author_rank: Frequent Contributor
timestamp: December 13, 2013, 02:52:51 pm
content: Quote from: nukie on December 09, 2013, 11:02:42 amSorry, I meant to say Japanese electros and SOME solids...here's an example fromhardwaresecrets.com test lab review:above: Seasonic-X-Series-KM3-650-W-Power-Supply-Reviewbelow:http://www.hardwaresecrets.com/article/Corsair-HX650-Gold-Power-Supply-Review/1705/5

author: SeanB
author_rank: Super Contributor
timestamp: December 13, 2013, 06:46:19 pm
content: Quote from: 13hm13 on December 08, 2013, 08:21:23 pmTell that to the UV leds in my office in a bank note detector that I rebuilt. They have been on test ( I want to see how they age) for about 4 months now on 24/7 at around 15-20mA ( depends on the mains voltage to the very simple power supply) and they are down about 50% in emission. Not that I expected much from cheap no name brand clear UV LED's, but they are definitely dying slowly at rated current through them.