Netcomm NB6 Routers - Bad G-Luxon

[c_hegge]

This is the fouth one I've seen get bad caps over the past couple of months. It's always been G-Luxon caps. I've been re-capping them with Panny FM and they've been fine after that. I'm gonna try FK with this one, since the FM caps are taller and I have to lie them down before they fit.

[japlytic]

Re: Netcomm NB6 Routers - Bad G-Luxon

Good repair job.
I also recommend replacing the three other capacitors that are not bulging as well.
Most equipment with poor quality electrolytics typically fail after three years, but this is an example of a unit which has failed over two years.

[c_hegge]

Re: Netcomm NB6 Routers - Bad G-Luxon

Here it is now with the Pannys. I'm using it for this post. I used FC for the three small caps and FK for the two bigger ones.

[jonesy63]

Re: Netcomm NB6 Routers - Bad G-Luxon

I just repaired my brother's Dynalink ADSL modem last weekend. It was having drop-outs every hour or so. I found it had two bad 220uF caps (the ones at the bottom of that last photo) - which were rated at 85c. Replaced with some Rubycon 105c caps and no dropouts for a week. All the other caps were rated at 105c, so stupid bean-counters strike again. >-(

[paul_h]

Re: Netcomm NB6 Routers - Bad G-Luxon

Bumping the thread because the OP seems still active, and is in Australia too.
I've got the same problem with my netcomm nb6plus4W modem/router/WiFi
It has a different board layout though.
Where most of your caps are, I just have one single 12x15mm 25V 2200uF g-lux SM

And where your Linkcom chip is, mine has 3 caps bunched together
8x15mm 25v 1000uf g-lux ?? cap
10x15mm 25v 1000uF teapo SC cap
10x15mm 25v 2200 g-lux SM cap

I've had no luck finding anyone selling caps only 15mm high, let alone 8mm or 10mm diameter. I suppose I could bend them over on long legs, but then I would still need small diameter caps I guess. So where can I get them? And what model?

[mariushm]

Re: Netcomm NB6 Routers - Bad G-Luxon

There's a high chance they don't have to be rated for 25v - they probably chose such high voltage rating to get lower ESR/impedance values and higher ripple from those G-lux and Teapo.
With better series of capacitors, the same low esr/impedance and high ripple values can be achieved by capacitors rated for less voltage and smaller

Get a multimeter and measure the voltage between the wires of those capacitors. If it's up to 14v, you can safely go with 16v capacitors (smaller and thinner).

My guess is the router is powered from an unregulated 9V adapter, which means the capacitors will be hit with anything between 9 and ~12v depending on the load, so you can probably go with 16v capacitors without worrying about it. But just to be safe, measure the voltage between the capacitors wires first.

As for brands, search on element14 for Nichicon HM/HN, Panasonic FM , Rubycon ZLH or ZL*, UCC KZE ... ZLH and HM are probably going to fit there, FM I know it's a bit larger in diameter.

[paul_h]

Re: Netcomm NB6 Routers - Bad G-Luxon

Thanks, I'll check the voltage in the morning.

[paul_h]

Re: Netcomm NB6 Routers - Bad G-Luxon

I checked voltage at the caps to the input ground from the 12v external plug transformer, (and I didn't know where else to check to).
It's 9V at the caps.

[paul_h]

Re: Netcomm NB6 Routers - Bad G-Luxon

I had a look in the shed as I have heaps of old PCBs for fridges and a/cs. they had a ton of 25v caps on them, all rubycon yxf (so at least one electronics industry has decent caps, sharp refrigerators and daikin a/cs had nihicon)
I had a go soldering them in but modem now dead. It turns on, all lights that should be on are on, but can't connect over ethernet.
Do you think it's because the yxf is too out of spec or that I probably fried something heating it up so long to try melt the lead free solder - never had much luck with that? Whatever the sharp pcb had for solder was like old solder, but whatever netcomm used was crap.
It could be that the yxf is too out of spec, but the modem worked before with completely stuffed and swollen caps. It just dropped out every few hours or when there was an incoming phone call, when connected it ran normally (full speed ADSL, wifi worked etc)

[mariushm]

Re: Netcomm NB6 Routers - Bad G-Luxon

Those 3 capacitors should all have the same 9v on them.

Near the jack, there's a capacitor that "buffers" the power coming in from the 12v transformer, so that one should get 12-14v.
From there, there's an actual voltage regulator (I can see the inductor it needs on the left of the capacitors) which converts the input to 9v.

But anyway... yes, YXF should be fine. Did you fry anything? Unlikely. Make sure you soldered each one correctly, check the polarity, the minus on each should be as the old capacitors were mounted.

Check the dc adapter with a multimeter - is it really 12v or around that value? Maybe the adapter is gone.

Can you connect to the router using a network cable and try to access the internal interface (usually http :// 192.168.1.1 or .100.1 or something like that) ?

[paul_h]

Re: Netcomm NB6 Routers - Bad G-Luxon

I can't connect with a pc at the IP address 198.182.1.1 i could before.
Cap polarity is fine.

I think I did a bad solder job with my old 30W iron though, really hard to desolder the original caps.
So I'm looking at getting a decent soldering station.
Most here are $200, but I noticed I can get a weller DES51 solder station from US amazon shipped to australia for $100.
Is it worth it as $100 is the max I can spend, and I need to recap a PC mobo soon anyway so I'm looking to upgrade the iron anyway.

I will get some proper matching caps and wait for the soldering station to arrive if it's worthwhile, probably get a new modem tomorrow anyway as well, and just practice on this one I likely stuffed.

It could be a adapter, as i couldn't read 12V anywhere, 9V was the highest, most places only read 7V. Strange I couldn't measure any voltage with no load, ie the bare plug from the adapter was 0V when unplugged from the modem but still plugged into the wall??? Using my fluke 87 iii.

[kc8adu]

Re: Netcomm NB6 Routers - Bad G-Luxon

is your wallwart ac?
that would be right if it uses a bridge and the input caps are open.
if its dc then the walwart/smps is bad.

[paul_h]

Re: Netcomm NB6 Routers - Bad G-Luxon

Yeah, I'm retarded. Sorry, it is an AC wallwart with 15VAC out of it, so used to testing DC ones.
I'm not crazy after all power wasn't coming from thin air, it's just that I am an idiot sometimes.

[Agent24]

Re: Netcomm NB6 Routers - Bad G-Luxon

Here it is now with the Pannys. I'm using it for this post. I used FC for the three small caps and FK for the two bigger ones.

Is it still working?

Can you tell me which model capacitors you used (sometimes there are multiple versions of one value with different can sizes etc)

[c_hegge]

Re: Netcomm NB6 Routers - Bad G-Luxon

^
We still use that router at work, and it still works to this day. IIRC, I used http://australia.rs-online.com/web/p/aluminium/0571656/ to replace the two bigger ones, since they were the only ones with a high enough voltage which would fit. Any Panny FC should work for the smaller ones.

EDIT: http://newzealand.rs-online.com/web/...inium/0571656/ for RS New Zealand

[Agent24]

Re: Netcomm NB6 Routers - Bad G-Luxon

Thanks, I'll have to give those a try