AT&T DumVerse

San Francisco takes earthquake safety seriously. Every batch of concrete gets tested. Welds are inspected. Bolts get pull tested. Current wood construction has steel beam reinforcement, plywood shear walls, all sorts of brackets and stuff.

Eh, maybe, but San Francisco is known for corruption. In any event, ICF is the way to go. It costs about the same as wood, but takes a lot of shady laborers out of the formula. [Hint: inspects don't inspect every last freakin' nail.] They can even poor roofs out of ICF these days.

ICF is steel reinforced concrete with foam on both sides. Fine in earthquake country, but as you know with concrete, the failure is kind of binary. Things are great to a point, but once concrete failed, the fecal matter hits the fan. Wood had the same problem, but at least the rubble is lighter.

Concrete testing is nothing unique to SF. In fact, everything you mention is routinely required in Contra Costa County.

SF land for the most part is very poor regarding earthquakes. It is fine for the steel high rises that are well engineered. But for a shack in the Sunset, nah......

In the bay area, the most expensive property is often on the crappiest land. Palo Alto and the good parts of Menlo Park for instance.

Mild steel, tensile strength 400MPa if cold drawn, so 400N per square mm or 25/4*pi*400 = 2500piN

About 800kg

should be good for about 10 SETM if a static load.

Turn off the ATT wifi and hard pipe it to your own wireless router via its hardware port (yes, it does have one). Then, you can use a better, newer router and mount it outside that box to better feed to household.

Allowable tensile force for a threaded rod is 0.33*Fu*pi*d^2/4

Using 0.185" for the nominal diameter of a 10-32 threaded rod and

Best regards, Spehro Pefhany

You're reading comprehension is really bad.

Indeed your reading comprehension is.

Though I think, in your mental derangement, you purposefully twist the meaning of other's comments. ...Jim Thompson

You can't even try to design a wideband, low capacitance, precise constant-current source!

Ex-Master-Circuit-Designer, you are.

Our building was built in the 1930's. It has concrete sides and wood floors, and sits on sand at the north edge of the Mission liquefaction zone. 1930's concrete wasn't that good to begin with. It was a prime candidate to transition from 50 feet high to 5 feet high in a few seconds.

We added huge concrete footings and three steel frames, and literally tons of epoxied bolts, brackets, and plywood. The city did inspect everything, including the nailing patterns on the plywood. The concrete was crush tested, and the epoxied bolts were pull tested, by an independent consultant. The city was very cooperative, probably because the seismic upgrade was voluntary. They were very reasonable about the handicap requirements, too. I was suprrised. Our contractor said that he had heard of one small corruption incident in his years working in The City.

That was all sort of fun.

We could do that, but the wifi is already there and configured. We could disappear the box door, or swing the wifi box out on its cables, just outside the metal box, and mount it on the wall. Maybe.

How could they be this dumb?

Am I getting this correctly? They put a wireless router INSIDE a steel box? That's not going to work without a coax cable run to an outside antenna. I don't recognize the black box but if there's no external antenna jack, the only option is to remove the door and replace it with something more RF transparent.

That's aesthetically disgusting. Replace the door with something else.

Kinda looks like the steel door can be removed at the piano hinge and replaced with a sheet of plastic or wood. It also appears to be someones structure wiring cabinet that's not really installed very neatly. You might suggest that the black box be mounted to the wall instead of hanging from the CAT5 wiring. Examples of how it could or should be done:

Or just run some coax to an external antenna.

Cheers

Phil Hobbs

Yup. That was my point. See pics I posted.

That's not going to work without a coax cable run to an

Do routers often have antenna jacks? Mine don't, but I didn't examine her AT&T router closely. Next time. She also wants track lights, dimmers, all sorts of daddy-job stuff.

I don't recognize the black box but if there's no

A plexiglas door is one option. Or maybe swing the wifi outside the steel box and Velcro it to the adjacent wall.

Cool pics, extremes of neatness and horror.

Yup, which has an advantage-- any of the stuff in the box could burst into flames and it would surely be contained by the steel box. An external antenna is very, very unlikely to burst into flames no matter what faults may occur within the box.

That rf shielding box will never pass FCC. Let's fix it. It needs some that beryllium copper spring gasketing, for starters.

-- Cheers, James Arthur

Coaxing thru to an external antenna defeats the whole point-- that releases all the 'fraidiation and launches it _straight_ into the _air_!

-- Cheers, James Arthur

some do, that's why there's reverse SMAs

some regulation says you have to use a special connector so people can't just add a different antenna

but ofcourse now you can get reverse SMA everywhere

-Lasse

I have a couple of them that do. Also there are lots of access points that use ~8 inch whip antennas.

Cheers

Phil Hobbs

Reverse TNC.

s/SMA/TNC/

Todays high fashion acronym infested wireless routers tend to use multiple internal antennas needed to make MIMO (802.11n) function.

I had a little fun yesterday at Best Buy. They had about 40 linear feet of shelf space devoted to routers and switches. I asked the sales person if they had any non-wireless routers. Nope. So I asked if they had any wireless routers with removable antennas. Nope.