CapXons about to blow their top - Page 1
Forum section: electronics / repair

author: TomS_
author_rank: Frequent Contributor
timestamp: December 20, 2015, 10:05:06 am
content: This device (Cisco 877W broadband router) has been running like a champ for 8+ years at least. Popped the hood to have a look at how well it was fairing internally having been in a beach side property for about the last 7-8, everything still looks pristine but there are two CapXon caps that are starting to bulge.Every other cap appears to be a Nichicon and appears fine.Unfortunately don't have any tools as this is at my parents house in Australia and I live in London, so it'd either be 1 more year and bring my tools with me, or I buy tools and caps while I'm here, or I replace the router now and bring this one home with me and fix it back in London.How long would I have left on these before I should replace them? Guessing they would be fairly close to popping/fizzing out by now...!?

author: DimitriP
author_rank: Super Contributor
timestamp: December 20, 2015, 10:34:01 am
content: Kinda hard to predict when it will fail.No neighbors with a soldering iron?Other than "do nothing" , replacing it is most obvious answer.Then you don't have to worry about how long it will last or your parents having to deal with it, or buying tools you already have to use once.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 20, 2015, 10:52:44 am
content: Yeah didn't think it would neccessarily be an easy thing to predict. And I'd definitely prefer not to have to rebuy tools. My dad is highly unlikely to use them afterwards.Another question, are Nichicon generally considered a decent brand? I've just realised that a lot of the smaller caps are tilted with a bit more lead showing on one side than the other. It doesn't really look like there's anything bulging out the bottom (kind of hard to see, might try tomorrow in the sunlight), no signs of leakage, maybe just that they were soldered in a bit wonky?What's a usual failure mode for these smaller caps, will they start to push out on one lead first?Just trying to work out the extent of the refurb required. :-)

author: jitter
author_rank: Frequent Contributor
timestamp: December 20, 2015, 12:39:19 pm
content: Quote from: TomS_ on December 20, 2015, 10:05:06 amIn my book a bulging cap has actually already failed and it's just a matter of time before its guts are going to be spewed out. This router may appear to be working fine, at the moment, but I wouldn't be surprised if stability issues or intermittent failures are about to occur soon. The wear/failure mode of 'lytics starts slow and then accelerates faster and faster due to the physics involved. The bulging indicates a pretty advanced state of wear and tear. Definitely not wait another year.Personally, with a 7-8 year old router, I would just replace it with a new item now and not bother repairing it. IMHO repairing it could be false economy. This old router may well be a bottle neck if it's the oldest part in the system. The new router would most likely have better bandwidth, wired and wireless, and a lower power consumption. Other bonuses might be a friendlier user interface and better security.Edit: in your last photo, I'm looking at datecodes of late 2005, early 2006. That router may be even older than your estimate.

author: madsci
author_rank: Regular Contributor
timestamp: December 20, 2015, 12:57:48 pm
content: They have already failed.If you were to pull those out and put them on an ESR meter, the ESR would be far higher than spec. The device likely still works because of filtered power coming from elsewhere or a good built in safety margin in the design that allows the device to function with sub par filtering.As for knowing when a small cap has failed, that's tricky.Non catastrophic small cap failure mode is a gradual loss of electrolyte via evaporation. There is usually no visual sign of trouble. I use intuition...is the cap in a hot area? Is the circuit the cap is in malfunctioning in a manner that suggests faulty caps? If so, test and or change the caps and see what happens. This intuitive method is how I got a big JBL amp to stop its protection circuit shenanigans after all the test points in the service manual tested good.One very notable exception for small cap leakage being invisible is Matsushita caps made from about 1975-1985 or so which leak at the lead seal and cause the leads to become green with corrosion. This particular fault has felled many pieces of Technics brand equipment and creates an opportunity to get a nicely designed bit of audio kit for cheap if you're willing to quite literally change ALL of the dark blue sleeved capacitors under 2200µF. The lavender sleeved caps from Matsushita don't tend to fail in this manner nearly as often but I usually change them out too.Of course, new Matsushita/Panasonic caps are just about bullet proof and have been since the late 80s. I use them extensively and in warranty repair rates are nil.

author: voltz
author_rank: Frequent Contributor
timestamp: December 20, 2015, 03:10:17 pm
content: If you're thinking of coming back a year later with tools, try getting your tools through airport security! They wont like it.Looks you may have to repair it on site with new (cheap) tools or find someone local (like a radio ham etc) and get some help. But you should be able to get a cheap iron from somewhere.. It only needs to work once.Those Caps looks very low voltage rated at 6.3v. I would uprate those to say at least 10v. Should last longer.good luck.

author: PA0PBZ
author_rank: Super Contributor
timestamp: December 20, 2015, 03:18:02 pm
content: Just buy the cheapest iron you can get, some solder and new caps, replace the caps and throw away what's left. Done for under $20.-

author: helius
author_rank: Super Contributor
timestamp: December 20, 2015, 03:35:46 pm
content: Nichicon are one of the most trusted capacitor brands, alongside United Chemi-Con and Rubycon, but like those their brand is sometimes faked.The leads are uneven because that's how they were stuffed, it doesn't tell you anything about decay. Signs of small electrolytics decaying will be the plastic jacket getting stretched so the metal case begins to protrude above the jacket. They could still be out of spec before that happens.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: December 20, 2015, 03:57:05 pm
content: Ask around - perhaps a neighbor has some tools.

author: wblock
author_rank: Regular Contributor
timestamp: December 20, 2015, 04:12:39 pm
content: Is it worth repairing an eight-year-old router? Any other brand, and the answer would usually be no. Cisco claims it supports WPA2, so apparently they have been updating firmware.2005 and 2006 were during the capacitor plague. Capxons were prone to failure. Nichicon is a good brand, but they and other higher-end brands also had problems during that time. So the two Capxons might just be the first. There might be more in the external power brick. The photo does not show the other side of the Capxons to identify the series. If they are a low ESR type, can you even get low-ESR caps locally, or be there long enough to order them?As far as soldering, just removing those might be challenging. The multilayer boards really suck the heat away, and some of the early lead-free solder was terrible stuff that preferred not to melt, ever. Even with a good soldering iron.I'd probably replace it and take the failed unit back to repair with proper tools and supplies.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 20, 2015, 07:17:11 pm
content: Quote from: voltz on December 20, 2015, 03:10:17 pmCheck the rail voltage first. Most routers have the main rail running at 3.3V and a 6.3V cap would be more than good enough. But those are big caps so I suspect they're supplying the power for the PAs and those commonly run at 5V in higher end routers. In that case, going up to 10V can be a good idea. The increased ESR on that rail will most likely just cause loss of range, which might be why it still seems to work.I don't really recommend Cisco nowadays. It seems like Netgear and TP-Link are the brands they buy at work nowadays. I've had plenty of issues at work with the Cisco AP used in a test setup. (Still way better than the "soft AP" they decided to put in a new setup, but that's another story...)

author: dundee
author_rank: Regular Contributor
timestamp: December 20, 2015, 08:54:52 pm
content: CapXon... desoldered them today from a cheap power supply:

author: voltz
author_rank: Frequent Contributor
timestamp: December 20, 2015, 09:09:11 pm
content: QuoteThe idea was if the Caps have broken down, you can pretty much guarantee this is a 5v rail. And he does not have a test meter or any other tools for that matterJust uprate them if possible. 10v is prefect for a 5v rail. The 6.3v caps would have been a cost cutting 'built in obsolescence' exercise to save money. 6.3v is the bare minimum for operation - lucky if you get a few years out of them at that rating. Just saying. That's my advice. Good luck.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 20, 2015, 09:18:10 pm
content: Quote from: NiHaoMike on December 20, 2015, 07:17:11 pmIve had TP-Link, and will never buy it again.Ive had the worst run of luck with TP-Link over the last 2 years, it just re-affirmed the reason why I never bought TP-Link in the first place - its just cheap crap. One unit I bought wouldnt pass IPv6 packets - its 2015!!I also had a little USB powered AP which was great when travelling, but like a colleague, it died after about 3 months.For me, Cisco is the way.Quote from: jitter on December 20, 2015, 12:39:19 pmIt quite probably is older than the dates I quoted, I bought it second hand, probably a couple of years after it was made and the business that bought it originally depreciated it or some such. Based on date codes I see on all of the chip packages, probably late 2006.Its a good router. I work as a network engineer by trade so I know how to drive these things. The Interface is a CLI rather than a GUI and although there is a GUI you can use with it, you can do more on the CLI than you can with the GUI.Its definitely not the worlds fastest router, but when all you can get is ADSL2+ its still pretty good. My parents are pretty light on Internet usage too, so even though its only got 802.11G wireless at best they'd be hard pressed to even work up a sweat with that.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 20, 2015, 09:21:20 pm
content: And thanks to everyone else for their replies. Currently looking at upgrade options for this router, and if I can work that out I'll bring this one home with me and do repairs where I have proper tools.I have another use for this router elsewhere once I repair it, so no wastage.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 20, 2015, 09:24:52 pm
content: Quote from: wblock on December 20, 2015, 04:12:39 pmOn the back of the caps is written:KF 105 deg CC6 02VENT

author: wblock
author_rank: Regular Contributor
timestamp: December 20, 2015, 10:35:58 pm
content: KF series is low ESR:http://www.capxongroup.com/files/2016-catalog-139-KF.pdf. Ratings on low-end capacitors usually have an element of wishful thinking to them, those are rated at 2.3 to 3.2 amps ripple and 2000 to 5000 hours at 105C.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 21, 2015, 04:25:19 am
content: Quote from: voltz on December 20, 2015, 09:09:11 pmOr they're dealing with a large ripple current, in which case increasing the voltage rating will not help. In particular, dual/triple band MIMO routers (which that one is not) can have a large combined load as the PAs used in some high end routers draw about 1A each when transmitting.What PA chip(s) does that router use? The datasheet would then tell us what voltage the PA stage runs on.

author: jitter
author_rank: Frequent Contributor
timestamp: December 21, 2015, 08:07:49 am
content: Quote from: TomS_ on December 20, 2015, 09:18:10 pmWell, I won't be making decisions based on past experiences again, neither good or bad... I recently got taught this lesson with a Canon multifunctional.I used to have an MP550 which worked a treat until it broke after about 5 years and lots of prints. Based on this good experience I replaced it with an MG5650 without looking at reviews. It turned out to be a pile of utter crap. Lesson learned.I did read reviews on routers before I bought one, and that led me to a TP-Link (TL-WR1043ND, V1) of which I have no regrets whatsoever. It and its wall wart (usually the weakest link) have been working flawlessly for several years now.But results can vary, whatever the brand that's on it, so the next one may not be a TP-Link.QuoteI used to have this reasoning as well when I still had a 25 Mbps internet connection. I used a cheap Cisco router with 10/100 Mbps LAN thinking this should be more than fast enough for the job. Well, long story short: this router imposed the same speed limit on the LAN connections as the WAN (internet) connection. So transferring data between my devices, all with gigabit connections, never went past 25 Mbps until my ISP decided that 100 Mbps was going to be their slowest speed. All of a sudded my LAN also went to 100 MbpsSuffice to say that shortly after I had discovered that, I bought a router with gigabit LAN.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 21, 2015, 08:37:50 am
content: Quote from: jitter on December 21, 2015, 08:07:49 amNot Cisco as in "used to be Linksys" Cisco, but proper "used in enterprise and service provider" Cisco?Ive never heard of something like that happening with the enterprise/service provider models.... It just seems ridiculous, coincidental, not possible for such a stupid thing to occur?!?For me, ent/SP Cisco has been flawless for the last +/-15 years that Ive been using them, theyve got a pretty decent track record for me that would be hard to beat. Ive been through a handful of consumer brands, but none of them cut the mustard. But I probably have slightly more "eccentric" use cases for my routers, I run IPSEC and routing protocols like BGP, forming my own little VPN (aka playground) between friends and family. You cant do that with most off-the-shelf consumer brand router unless you flash it with one of those 3rd party images ..... the names of which escapes me right now as I type this.But ent/SP Ciscos, particularly the lower end models, have never been known for raw performance. They might have 10/100 even gigabit ports on them, and while you may be able to switch data, i.e. Layer 2, at those speeds you'll be hard pressed to route, i.e. Layer 3, at those speeds. They arent necessarily built for performance, just lots of features, some obscure features that various enterprise customers need for their LANs and WANs. You cant chuck something like a 2600XM with two 10/100 ports in somewhere and expect to get anywhere near 100mbit through it just because it has 100mbit ports... Suffice to say, if youre going to buy a "proper" Cisco, do your research first. Understand what it is the box was designed to do in the first place, and buy accordingly.

author: jitter
author_rank: Frequent Contributor
timestamp: December 21, 2015, 09:01:37 am
content: Quote from: TomS_ on December 21, 2015, 08:37:50 amIt's a cheap consumer type router (WRT54GH). It says "Cisco" on the top, but on the sticker on the back it says "Linksys by Cisco".QuoteOpenWrt?If it's an enterprise Cisco, I can understand why you would want to repair it.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 21, 2015, 09:11:45 am
content: Quote from: jitter on December 21, 2015, 09:01:37 amYeah, thats the one! Drew a total blank on that. I think theres a couple of others, but OpenWrt is the more popular one from what I can gather.I guess its not so much because its an enterprise router that I want to fix it, its more of a "its been working so great and does everything it needs to do, why change it" kind of thing.Unfortunately its probably a bit of a ticking time bomb now, so will have to do something about it.

author: jitter
author_rank: Frequent Contributor
timestamp: December 21, 2015, 09:39:41 am
content: Quote from: TomS_ on December 21, 2015, 09:11:45 amAgreed, those CapXons are about to blow (literally). But their state also has me wondering about those inside the powerbrick.I recently repaired a cheap WiFi repeater in which the 'lytics in the secondary side of the PSU had failed. I neglected to replace those in the primary side which looked fine, no bulging at all. Less than two months later the thing failed again. You guessed it, now the primary caps had gone...If I were in your place, I would probably still buy a new router for the parents.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 21, 2015, 06:32:26 pm
content: I used to have a 24 port Cisco 10/100 switch that worked just fine for over 10 years. The switch itself was made in 1996, I got it used in the early 2000s, and retired it in 2009 or so when I decided to upgrade to gigabit.Contrast that to a Cisco VPN router I bought new in 2005 and it started going intermittent after two years, while a cheap Belkin router of about the same age was still working fine. Three of my friends have also had Cisco routers break down on them in 2-3 years. Cisco seems to be just like HP - once considered one of the best, now one of the worst.

author: madires
author_rank: Super Contributor
timestamp: December 21, 2015, 06:59:39 pm
content: Quote from: NiHaoMike on December 21, 2015, 06:32:26 pmThere is a huge difference between Cisco's consumer stuff and enterprise/service provider NEs. If you are looking for consumer stuff, there are better and less expensive products from other manufacturers.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 21, 2015, 09:08:14 pm
content: Quote from: madires on December 21, 2015, 06:59:39 pmExactly. I think they tried to brush off a bit of their "expectation of quality and things" on to Linksys when they bought it by plastering their logo all over that stuff.But it was still designed as consumer gear, and probably "cut a lot of the same corners" that other consumer gear used, so you still got the consumer experience regardless of the Cisco logo. Possibly a bad move on their part...The Cisco gear Im using runs IOS and has serial console ports that are deliberate - the real stuff. :-)

author: jitter
author_rank: Frequent Contributor
timestamp: December 22, 2015, 11:29:31 am
content: Quote from: NiHaoMike on December 21, 2015, 06:32:26 pmMy advice would always be to first try another AC/DC adapter (aka wall wart, plug pack, powerbrick) of suitable ratings before condemning the router/modem/whatever is powered from it. I've had routers, modems, repeaters and media players fail on me, most with intermittent symptoms at first. So far it *always* turned out to be the power supply (wall wart or built in) and not the actual device itself.I then either repaired the built in PSU with decent caps or replaced the adapter with a 50% higher rating (e.g. from 1 A to 1.5 A). This increase in capacity greatly increases life expectancy and usually costs only a few $/€ extra.

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 22, 2015, 06:57:38 pm
content: Actually, I opened the router itself and it was bad caps. I replaced them with some surplus OSCONs and it was good to go for a few more years. Also fixed another Cisco for a friend and it was also bad caps. But those power supplies do often fail.13.6mF is a lot of capacitance especially for an old G router. My AC1200 Trendnet, in contrast, came with a 1000uF cap on the PA supply rail, which I upgraded to 2200uF along with a few other upgrades like better cooling and high gain antennas.

author: nukie
author_rank: Frequent Contributor
timestamp: December 22, 2015, 10:41:05 pm
content: Quote from: voltz on December 20, 2015, 03:10:17 pmHey school holidays is it???I travel with an assortment of electronics tools that isn't small, europe, Asia, usa, been checked by quarantine X rays no questions asked. There was once two rolls of solder was mistaken for handcuff in Singapore, was asked to open my bags, that was it. I fly five times a year. Always check in my tools. If i cant bring my tools then my job is gone. Please don't spew nonsense here keep your bullshit to your self, merry Christmas.

author: TomS_
author_rank: Frequent Contributor
timestamp: December 22, 2015, 11:07:40 pm
content: Quote from: nukie on December 22, 2015, 10:41:05 pmExactly. Theres generally no issue with tools in checked luggage. You'd be a fool to try and bring them with you as carry on.I travel frequently for work, and bring a Peli case full of tools with me, from knives to screw drivers and spanners etc. I just check it in and have never had any grief from security.I have however, accidentally, managed to get a Leatherman through security - twice - without it being detected. Was tucked away in the bottom of my backpack. I had wondered where it was...

author: Stonent
author_rank: Super Contributor
timestamp: December 23, 2015, 12:05:44 am
content: Quote from: helius on December 20, 2015, 03:35:46 pmFor repairs like this, even genuine nichicon, rubycon, nipponchemicon or panasonic caps are only 10 to 20 cents each if you can get them from a reputable supplier.You might check local TV repair shops and see if they will sell parts from their stock.

author: nukie
author_rank: Frequent Contributor
timestamp: December 24, 2015, 10:54:38 am
content: Quote from: TomS_ on December 22, 2015, 11:07:40 pmI did this many times, only stopped once before the 9.11 incident. It was accidental at first but after a few times I didnt care anymore. Its funny they want to look at my wifes little rounded end scissors but they completely miss my multitool with 2" blade and you know how much damage can a Leatherman wave saw can do? Carrying multitool onboard has been normal for me those security checks are useless.

author: SeanB
author_rank: Super Contributor
timestamp: December 25, 2015, 07:04:27 am
content: Quote from: nukie on December 24, 2015, 10:54:38 amI carry a knife and a multitool in my wallet all the time. Took 3 years for the bank security to notice it, even though it went through Xray every time. After the first time I just simply moved it to clip on my shoe when going there, as I wear steel capped shoes it does not show as I tripped the metal detector every time with them, so they were used to it. Eventually they wised up that this was just very expensive security theatre, and removed it all. Improved and probably more secure, as here the major danger is not terrorism, not by a long shot. Armed robbery is by far the most common, and the government wants to disarm the legal gun owners while doing little to curb the supply of illegal firearms.

author: BradC
author_rank: Super Contributor
timestamp: December 25, 2015, 11:20:03 am
content: Hell, there are plenty of Aussies here. Why not ask if anyone in the general vicinity would mind giving you a hand to procure and replace 2 caps. Can't be more than 3 beers work.