Electronics Advice

[Cursitor Doom]

There is an active group - sci.electronics.repair - which may be also of use wrt these kind of questions.

[Johny B Good]

Hence the use of newspaper to help gather the worst of the solder droplets and splashes, followed by judicious use of a brush and dustpan afterwards. On balance, using the kitchen doesn't pose any health risk even assuming tin/lead solder.

[John Rumm]

Sometimes just allowing for some loss with ageing...

[John Rumm]

Which is frequented by several experienced electronics designers, and a number of professional electronics repairers.

[meow2222]

I'm not suggseting its not

NT

[meow2222]

and...

NT

[meow2222]

soometimes yes, often not. So one cant assume

When youre dealing with rectified power thats often incorrect.

depends entirely on the design ethos

If you want to put in a smaller cap with higher ESR and lower temp rating you can. The results are predictable, more noise & shorter life. Sometimes it translates into a practical problem, sometimes not.

NT

[Johny B Good]

Ok, you win that one. :-)

[Johny B Good]

I didn't follow the link, Doh! I'd just assumed it was a repair to either a router wallwart psu or else a cap in the switching regulator in the router itself and just got hung up on the pros and cons of using replacement capacitors with alternative values from the original.

If I'd realised it was a repair on one of these hateful EM spectrum pollution devices, I'd have suggested a 100 microfarad 4v cap as a suitable substitute. :-)

[dennis]

Did you miss the one where I said take it back for a refund?

[Johny B Good]

I don't think any of us missed that so much as discounted your advice as spurious and unhelpful.

Otoh though, if you had suggested that he fit the replacement cap the opposite way round on account the PCB was incorrectly marked and the original had failed due to reverse polarity, now _that_ would have been helpful. :-)

[dennis]

There is a well known fault in them. They should be refunded under the SoG act. Then the OP can use a proper solution.

[CB]

My research before posting had located a guide on how to repair them in the event of a specific capacitor failing. I had opened mine up, confirmed said capacitor had failed and removed it; I now had options for the replacement - which I then asked advice on.

By this time "take it back for a replacement" was one of the less helpful replies I received.

But even now with further research I cannot find any information on the web about a "well known fault" that I could use to support a replacement claim on something that had been used continuously for 2.5 years.

Can you give me some pointers as these things come in pairs you know, and if its a common fault I guess the other one wont be far off failing.

Chris.

[The Natural Philosopher]

Go for same or bigger with electrlytics.

out of warranty. Not worth it. repair.

juts replace the ruddy lot if its a single manufacturer

[robgraham]

a reason they went up to 1500 in such a tight space.

en voltage costs more. So 1000uF cap can not be assumed to have enough capa citance.

ance range, with the minimum value 2/3 as much for the 1000.

Two things to add in from a recent experience.

I was given a dead HP printer - dead in that it powered up then almost imme diately powered off again; an extensive internet search located a forum cov ering this, and possibly lots of other printers, which were all fitted with capacitors from a specific Chinese manufacturer. The story goes that one m anufacturer was suspicious of industrial espionage and allowed a doctored f ormula to be released - three to four years later a lot of electronic syste ms went t*ts up with bulging caps.

I had four to replace. I'm from the electronics industry and will warn tha t getting such capacitors out, clearing the pcb holes of solder and getting a new one in is not that easy with modern solders and multilayer boards.

I did succeed and the printer works well, but I had difficulties removing t he offending items, and in the end, with much trepidation, I had to drill t he pcb holes clear of solder, having got all but a modern desoldering stati on.

[Johny B Good]

No argument (now that you've reminded us that the item in question is a PLA).

No dispute about that.

Such as ethernet cabling or, if needs are modest, a wi-fi repeater or Access Point.

However, Chris's question regarding replacement of a blown cap was what seemed to motivate all the helpful responses. If I'd realised what it actually was that he was trying to repair, I'd have simply just sat quietly on the sidelines.

[Johny B Good]

Preferably with ethernet cable rather than look for an alternative maker of such sources of EM pollution.

[alan_m]

The trick is to add MORE solder with fresh flux before attempting to clear the hole. Adding flux also helps to get the solder out of the hole.

For DIY electronic repairs don't use lead free solder.

[meow2222]

its easy if you dont clear the holes

NT

[Johny B Good]

Seconded. Lead free solder should be banned from general sale to the DIYer and, imho, it should be banned by law from the manufacturing process as well. Factory wave flow soldering is the one situation where the health risk of lead poisening/pollution can be reduced to zero.

The health risk posed by equipment assembled using lead/tin solder is extremely overhyped, again imho. You just have to ask yourself why critical medical care electronic equipment used in hospitals is exempt from this stupid "No Lead Allowed" nonsense.

The WEEE directive should automatically take care of any lead poisening/pollution issues that could arise out of the disposal of end of lifed electronic kit anyway, rendering the mandate to eliminate lead out of the manufacture of electronic kit somewhat redundent.

I dare say the OCD H&S brigade have touted property fires involving a house/shed/warehouse full of electronic kit as being a serious health hazard. It might be under the right circumstances but I believe this risk has been well and truly overhyped to our law makers. How many times in your life have you been within sniffing distance of a serious property fire? Once? Twice? Dozens of times?