I have a Zonet ZSR1104WE Wireless Broadband Router. It's about 3 years old, and until last night worked just fine. After a storm last night, the router quit working. It shows no signs of life.
I've tested the AC adapter with a meter, and it's showing 16V (no load.) So, I opened the case up and started tracing the circuit. One diode (D1, IN5.... (can't see the numbers)) near the power input has shorted (tests open both ways), but my question is where to go next? I've looked unsuccessfully for a fuse of some sort, the next components in the circuit are a B1412 transistor (Q5) and a choke (L1.)
From the B1412, the circuit continues to RT34063a (u9) and then to a series of resistors (R9-R5).
Any help would be appreciated.
Puckdropper
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A 1 amp diode should be ok for a test but I think you've got problems further down the line from my experience with lightning damage warranty repairs. I hope you don't though :)
If it works, use it and don't worry about the diode. :)
12 V at 1 A can't hurt a 1N400X.
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Meat Plow wrote in news: snipped-for-privacy@news.alt.net:
The diode was a 1N5817, a schottkey. Out of the circuit, though, it tested fine. Guess that means there's problems somewhere else.
I tried putting it back in, but ran in to problems with one of the holes filling with solder.
My guess is there's problems on down the line, and they're network side related. All three network devices I had (2 routers and a switch) are acting funny.
Puckdropper
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Wise is the man who attempts to answer his question before asking it.
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Yeh I've replaced loads of switches and other net appliances after lightning strikes when I worked for a networking company several years ago. Those things just don't tolerate it well.
Need a little more experience in sodlering -- don't you? Good techniques can be demonstrated in 5 minutes or less to a 'newbee' or garage tree home repairer -- and I have seen these devices ruined due to frustration, lack of patience and anger management issues.
Get some good solder wick and a sewing needle.
You may not have taken a direct hit -- it may have been an "induced" power surge.
You may also have damage through your Ethernet (10/100) ports.
I have seen an induced surge (from lightning striking within 500 feet of location) vaporize copper traces right off serial (RS-232) cards from external modems. That strike had no effect on AC, but rather came through phone lines -- right through external modem (back to Hayes) and to serial card (grounding through computer ground)
Jumpered the missing traces -- and everything worked (in my case).
"w9gb" wrote in news:Sq2dnXLemf2hqBjbnZ2dnUVZ snipped-for-privacy@comcast.com:
I was getting frustrated earlier, so I quit. I'll try it again later today, and hopefully get that hole cleared out without damaging the board.
Everything you said sounds like it's what happened. There's NO physical evidence of damage on the boards, all three devices are acting strangely. (Well, except the dead router.)
I've got a replacement router and switch on the way, I just wanted to try to repair the ones I have for the experience.
Puckdropper
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Wise is the man who attempts to answer his question before asking it.
To email me directly, send a message to puckdropper (at) fastmail.fm
It is routine for a direct strike to leave no visible damage. Also routine is for many to assume a surge entered on phone line when unknown is a protector installed on all telephone subscriber lines (for free).
Best evidence is the dead body. Damage is how a human learns where effective protection was missing; where a surge was permitted to enter the building.
How large was the surge? Routers already have effective internal protection. The surge had to be so large as to overwhelm that internal protection. The surge found earth ground, destructively, via that router. That is a direct strike.
Long after surge electricity was flowing through everything in a path from cloud to ground, only then something in that path failed. What died inside that router? What was the path through that router? A destrutive electical circuit formed by overwhelming internal protection because a direct strike was not earthed before entering the building. Learn from that damage so that future damage need not occur. It is routine to have direct lightning strikes and no damage; when an effective solution is installed. Use information from the 'dead body' - the electrical path in and out of the router - to find and eliminate the problem. Where did a surge enter the building? That is where a solution is installed.
The transient that BBQ'ed the router, could have scrambled the settings down stream. Follow the manufacturers instructions to reset defaults.
It hardly seems worth your trouble but I know the Holy Grail Syndrome all too well. No doubt, there are caps to ground, electrolytic, tantalum, film or ceramic, that are placed both before and after the diode. This should be the source of your short if the diode is in fact OK. You need to use the 200 ohm setting on a good meter to narrow things down. Touch the probes to each other to set or at least see zero ohms then probe each component directly, looking for the least resistance, then unsolder to verify.
Get yourself some solder-wick, rosin soldering paste and some quality solder (Sn 63 multicore tin/lead if you have a choice). Clean your iron's tip with scotchbright until you break through any dark oxide. Sometimes scraping lightly with a single edged blade is better. This is lead so, no food, wash hands etc. Do not scrape through the plating.
Heat the iron and dip it in the rosin as it's getting warm. Hold a piece of solder against it. As soon as it begins to melt, quickly coat the entire tip. Wipe the hot tip to remove excess solder and rosin, then apply a bit more solder. This is how the tip must look before it is put away and just before you use it, Bright, shiny and fully coated with a slightly noticeable bit of extra solder near the very tip.
The solder must be wiped and renewed just before each operation.
Touch the iron to the hole in question and add a bit of solder.
Remove the heat when it begins to flow.
Place the solder wick on top of the hole and press the iron on top of the wick. The solder should be drawn into the wick.
A solder sucker could also be used but fresh solder wick is a better bet for a beginner.
The terms "short" and "open" mean specific things in the field of electronics and people will misunderstand you if you use them interchangeably for anything that isn't working. "shorted" means that something does conduct electricity, "open" means that it does not conduct electricity.
i concur, impulse emf from millions of amperes flowing nearby does indeed do some remarkable things!
almost as if by majic, i had a coiled extension cord on a bare plank porch, it was clear of anything and completely unconnected to anything. after a strike about 30 feet way, it was melted and fused together, no copper showed any hint of black conduction damage, only the nice clean smell of lotsa heat!
better u spend time finding a replacement router than hours trying to fix this!
TMI wrote in news: snipped-for-privacy@n60g2000hse.googlegroups.com:
I tried that first. I think it's press and hold reset for 20 seconds, but it could be longer. I'm hoping the memory isn't fried.
There's about 5 of them near the power input. I'll give them a look and see what they're doing.
I don't have the rosin soldering paste, but I do have ZnCl flux. Is this the same kind of thing, or do I need to go looking for the rosin soldering paste?
I'll give your suggestions a try. I'm wondering if there's a lead free solder used on the board, due to the trouble I had desoldering the diode. (I had done other desolderings from other boards and this one was much more difficult...)
Puckdropper
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Wise is the man who attempts to answer his question before asking it.
To email me directly, send a message to puckdropper (at) fastmail.fm
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