harnessing lightning, or not

see my post

They are usually NOT exposed. ie under a sheath, nosecone, or dome.

see my post

Then there has to be an inductive path to ground farther upstream, at that amp. In aircraft electronics such stuff is usually done correctly and they have to follow stiff standards. Other areas, not so much, and there lots of them screw it up.

see my post

How's that going to help against lightning effects?

see my post

Telemetry equipment for the shuttle and ISS. Possibly AWACS, but the contract didn't really say. We did ship a lot of Telemetry equipment to DOD addresses and aircraft manufacturers.

see my post

What are they going to teach? It costs money to design hardened equipment, and some bean counter is always saying NO!!! Companies that are good at building hardened equipment treat there methods as proprietary information.

Sorry, but I don't work with crap.

see my post

An antenna under a dome or sheath will not be an attractor for lightning like a raw, exposed stick would, so the strike will be upon the craft, not the antenna. The only effect after that are the induced EM effects, if any.

see my post

Nowadays an inductor can be had for 2-3 cents. At least in China. Most of the time the cost change is zero because all you need to do is swing a filter architecture for T to Pi. Same number of parts but no more phhhht ... *POP*. Bean counters really like that :-)

There are applications where plastic isn't crap at all. Or do you think radio-translucent dome caps on aircraft are crap?

lightning, see my post

to

It is not about a direct strike, it is about coupled voltage spikes from strikes in the vicinity. If you don't have a conductive path right from antenna to GND that typically means more field failures. A lot more.

lightning, see my post

to

Not much of a "stick" at L1, L2, or the frequencies used by the geostationary sats for WAAS, as well as sat data/voice (eg. Iridium).

lightning, see my post

to

Most of the RF gear I work with has DC on the input so no matter how cheap the inductor is, it won't work. OTOH, I worked on $20,00 to $80,000 radios, not $10 radios.

They can be. I'm waiting for transparent aluminum. ;-)

lightning, see my post

throw a

so.

Hey,

heads

inductor to

that

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We called them Upper L and Lower L in the telemetry business. P band was common, too. All were tiny probes in a feedhorn.

lightning, see my post

throw a

heads

to

What part of the word 'induced' did you fail to learn in your study years?

lightning, see my post

throw a

heads

to

ANY sharp protrusion has a huge gradient difference compared to rounded or no protrusion.

The Iridium is a six inch long stick, BTW.

lightning, see my post

to

Same here. Except that my range does go down to around two bucks :-)

Yesterday I marveled at a friends project, he is building a Van's two-seater. Man, what an amount of work that is. All those rivet alone made his wrist hurt even though he has an air tool that he can use on many of them. And the aluminum is all scarily thin.

lightning, see my post

throw a

so.

Hey,

heads

inductor to

that

THE

That's why I am surprised you don't understand why there needs to be an inductor.

lightning, see my post

throw a

heads

to

I've seen (and remedied) situations where 2"-3" sticks caused massive field failures. Because the inductive path was lacking.

lightning, see my post

throw a

so.

Hey,

heads

inductor to

that

THE

For this reason a folded dipole is nice, since you can ground the midpoint of the upper (continuous) side. No extra inductors needed.

Spendthrift!

I did some body fork on a step van years ago. I used over 10 pounds of #6 1/2" self tapping panhead screws. There are over 650 screws to the pound. A lot of them went into aluminized stainless steel. That's the special steel developed for Catalytic converters.

lightning, see my post

throw a

so.

Hey,

heads

inductor to

that

THE

deployed

out

I sure wish I could find a 900MHz antenna like that right now. But it must be under 4dBi for license reasons and must be a vertical stick because of space constraints.

But, I guess, it'll be the usual. Fix the bugs the RF module mfgs let slip by :-(