Re: Soldering bypass caps to QFP possible?

Yep, unfortunately that's the situation :-(

Going for the system solution now (shielding around the whole board). It looks much easier to retrofit.

At GenRad, I always asked for (and got) a clear space for the analog... and I did the layout. Digital guys have no concept of ground or shielding or coupling :-(

...Jim Thompson

I wonder what is the interference path, (and why can't the static gun test it?).

- Conducted interference from the wires entering the case?

- Or radiated from nearby wires that themselves have conducted interference on them?

- Or direct EM radiation from the lightning?

Us consultants often have to pick up the pieces afterwards and try to save the day :-(

Number three ;-)

That's interesting. I can see that happening with cell phones held near - but for some reason I would never have expected a direct EM effect from lightning. Unless very close of course!

Not on this product, but I've seen other cases where traces have been vaporized, SOT23 diodes that had no plastic housing anymore, etc. "But the lightning only struck a fence post 20ft away and the circuit had not connection to anything ..."

in the late 90s our machine shop moved across the road (we expanded). The IT department asked R&D what to do re. ethernet, and was told "fiber optics". But that cost a few k, so they strung an ethernet cable up on the power poles, beside the phone lines. About 1km away (across the road from the company our former R&D mgr and senior engineers set up) lightning hit a ground-mounted transformer, and made a hell of a mess. the resulting EMP snotted about a dozen ethernet cards, and fried the brain operating an old turret-punch that had been upgraded from relay control to PC control. Ignoring the turret punch, it cost $3k to fix all the other PCs. The turret punch, being customised about a decade earlier by nobody knows who, was essentially unfixable. When the IT department queried R&D they got a great deal of laughter, and "WE TOLD YOU SO". After this little event, they bought the thousand bucks worth of fiber optics. I believe the turret punch got sold as scrap. oddly enough, nobody got fired.

Cheers Terry

Ouch! Fiber optics isn't that expensive. We even used it inside buildings for really long runs. Possibly you could have connected it all up on the cheap with a couple of wireless routers and directional antennas. Usually a machine shop doesn't need a whole lot of bandwidth. Wireless also avoids the telco guys wondering "What's this here cable doing up on the pole?" and then just snipping it off.

I believe that was for a COTS ether-to-fiber system. bear in mind that here on the arse end of the planet, stuff can be very expensive. A pair of Levi 501s willset you back NZ$120, and a pair of Dr Martens boots NZ$250. Which is why I buy my levis when in USA (< US$20), and docs in the UK (about 40 quid). somebody here is making a LOT of money.

I recently bought a nice Tek 4ch isolated scope & 3 AC current probes, from a dealer in CA. I had it shipped to a client in SF, and neglected to tell the dealer I was based in NZ, otherwise they wouldnt have sold it to me. The NZ tek agent wanted NZ$2500 more than the US retail price

• exhcange rate. thieving weasel!

Cheers Terry

Yep, that's how I did things when in Europe. Paid my import duty, VAT and all, so it was all legit. But this cut out the hungry middlemen. Software often had a 100% markup in Europe, probably still does.

For the next scope check out the GW-Instek series. Got their top of the line here. Handles IMHO better than a comparable Tek, cost >30% less. Love it. But it is a wee bit larger.

ditto. the prices I quoted were ex. GST.

I got the Tek scope because it has 4 independantly isolated channels. and cost less than 4 P5200 diff probes. when I tossed in the power calc module it was still less than 4 diff probes :)

Cheers Terry

Joerg,

It seems as though that ought to pay pretty well though, no? You're so frugal :-) I often start thinking you must not have a lot of income, but then you describe the projects you work on and it's clear you should be making a decent income! What are you doing with all that income? Saving it? Taking high-end vacations with your wife? Donating it to charities of your choice?

Just curious... :-)

---Joel

I guess an isolation transformer that's all of a couple cm on a side doesn't hold up real well against, 100kV...

That's when you're supposed to find some savvy high-school or college kid, hire them as an intern for the summer and tell them, "See that machine there? Make it work again!"

It probably would have been impossible to prove just how much less damage would have been done if the fiber links had already been in place.

Joerg is buying pellets for his stove ;-)

...Jim Thompson

SIMILAR THINGS HAPPENED AFTER THE FIBER LINK - NO DAMAGE. oops, sorry about shouting :)

Cheers Terry

Pretty damning evidence, certainly, but I don't suppose anyone was out for blood by that point, eh?

frugal

decent

high-end

Yes! And when it comes to beer, only the good stuff.

Frugality was taught by my parents and grand-parents. If it can be fixed, don't throw it away. Keep things simple. Buy only the good stuff because it'll last. Don't buy a bigger car, TV, whatever, just because the neighbor did. And so on. Works great.

I have yet to see where indulgence and luxury brought anyone true happiness. Of course whenever I read Flying Magazine that mantra goes out the window for a few hours ...

Ok, that's specialty stuff that you kind of have to buy at the mainstream mfgs. My turf is more at the higher frequencies where a diff probe consists of a piece of coax, a 0.37" #43 toroid and some wire.