Entry, ugliest ECO competition

Did it solve the problem? Needs stabilizing hot-glue.

Gnarly. The lead going round to the bottom is the pie`ce de re?sist ance. ;)

On the other hand, one has to admire the chutzpah involved.

Cheers

Phil Hobbs

(who uses blue wire-wrap wire for ECs on blue boards)

Man... any dog that sticks its nose out of the car window like that is _sure_ to end up running smack into the hind end of a wasp, and getting stung.

I've seen one that was at least as bad. Years ago I bought an Ethernet card, on which the manufacturer had ignored the chipset documentation and omitted about half of the 'absolutely required' bypass caps, including the critical ones right by the chip's analog rail pins. Just as the chipmaker had warned, the receiver suffered from ground-bounce and would drop bits on some packets.

When I complained, they sent me an ECO'ed card. They'd glued two .1 uF ceramic caps to the top of the Ethernet chip, and run long wires to the Vcc/Vdd pins. Possibly thanks to the parasitic inductance of the wires, the additional bypass capacitance didn't work for beans, and the card still didn't receive reliably.

We noted who signed the ECO approval.

Right, I figure it needs some goop, to hold in place.

George H.

I did worse once as a repair. To my surprise it worked fine.

NT

Yes. The VM rail is the shared VCC/2 reference for a dozen AC power amps. But each bleeds a little signal current into the bus, and each has a little gain from the bus, and there weren't enough bypass caps. So crosstalk.

We have got to remember to seed all our boards with a lot of ground test points. It was hard to find a place to ground this cap.

Use red wires and own up to your sins.

(What was that dreadful book they made us read in high school? The Scarlet Letter?)

It'd be extra nice if they were 'gnd' labeled alongside 'tp21' .

A few extra through-holes (with or without plated-thru) would make the mounting of a radial capacitor easier and more secure. That'd double for daughterboard attachment, just in case...

istance. ;)

The Scarlet Pimpernel?

NT

I went to high school in Canada in the '70s, so we got fed mostly modern local crap, e.g. The Stone Angel, Pilgarlic the Death, Duddy Kravitz, and The Manticore. My new-agey Grade 10 English teacher made us do a book report on Jonathan Livingston Seagull. (*)

Hawthorne would have been a great relief.

Cheers

Phil Hobbs

(*) He expected everybody to fall for the author's ridiculous Buddhist/Christian syncretism and compare the big cheese seagull to Christ. My mother, who was a philosophy major, put me on to Book 6 of Plato's Republic (the allegory of the caves). I got the Cliff's notes and hammed it right up. He loved it, and my punishment was that I had to read it out to the class. Took weeks to live that one down.

My school was pretty progressive; we had a very discreet sex-ed class that was probably illegal in Louisiana at the time. I think they had us read The Scarlet Letter because what's-her-name (Hester?) had actually Done It.

But they still made us read a lot of teen-boring drivel. Why not some PG Wodehouse or Raymond Chandler or even Jane Austen?

Back on topic, I think I'll create a new part TPG, which looks just like TP but has a silked square or hexagon instead of the circle. Those will be the obvious grounds without a lot of text cluttering things up.

Or just use thermals on the pad--the cross shape is pretty obvious.

Cheers

Phil Hobbs

?sistance. ;)

rn

Not in my layout program. Even for large pads it uses rather thin connecti ons across a very narrow gap. I expect this can be altered for any given p art. I just use a particular pad shape or better... label them with a circ le around them.

There would only be visible thermals if there were a layer 1 ground pour, which we rarely have. Ground is usually L2, hidden by the top solder mask and maybe 10 mils of FR4.

Too bad the silkscreen layer isn't in colors. I guess that could be done for dollars. But then that might get tacky.

Well, I'm the guy who approves ECOs.

The Hound of the Baskervilles

I'd never heard of the scarlet letter. A quick glance and I can see why. The hound of the baskervilles is ok, an old murder mystery.

NT

You were supposed to say "That's not so bad, John."