Electrickery

[PilotDAR]

That's not an EM wave you're looking at it's a electric signal made from a magnetic one....way different.

All you're looking at is a change in the magnetic field...not propagating EMI...not at all...

You need a transmission line to emit...not a single conductor...there must be an electric charge movement...impedance is crucial.

Okay... I'll play:

When I witness an EMI test, it includes the magnetic compass, and remote compass, if installed. A witnessed compass swing - required by TC, as an element of the EMI test = no successful compass swing, EMI compliance not demonstrated.

If the magnetic field in the aircraft, as the compass indicates it changes, because of a change to the aircraft electrical system, the electrical system change has caused and EMI affect, which requires resolution. I don't really care how the EMI affect was introduced (wave, propagated, transmission line or single conductor) it was detected, and is therefore present.

But, if I'm witnessing the test, it's probably already a major mod approval.

If an AME, or other aviation technical person, is witnessing the same test, they are already applying 571, Appendix A, and looking for an answer to:

(10) affect instruments, or indicators that are installed as part of a system required by the approved type design?

If EMI was detected (including an affect on a magnetic compass) (10) has to be answered "yes", and the design change just became "major". The modifier is going to require approved data (probably and STC) for it.

[CID]

All you're looking at is a change in the magnetic field...not propagating EMI...not at all...

James Maxwell would be really surprised as he and Heinrich Hertz proved that changing currents in wire do in fact produce electromagnetic waves.

Pull that coil away a few inches...what do you see? ...it's disappeared!...must be magic...

Not magic at all. The intensity of the field is proportional to the inverse square of the distance to the source. Thank Gauss for that.

You need a transmission line to emit...not a single conductor...there must be an electric charge movement...impedance is crucial.

Wow. Just WOW.

[DonutHole]

Lol. A GPS installation if for vfr use only is vied as a minor alteration by the faa, and as a minor modification by transport Canada. The policy letter says so explicit, as does the advisory circular it defers to.

Within the polixy letter it tells you exactly which specified data to use, it's clear as day.

Moving the generator to bus conductor in any certified aircraft is a major modification.

Pretty simple.

[NeverBlue]

changing currents in wire do in fact produce electromagnetic waves.

Actually no...the changing fields create EM waves...E fields exist between conductors...not around them...charges do...

You clearly do not understand the difference between E fields...H fields and propagating RF fields.

[CID]

Within the polixy letter it tells you exactly which specified data to use, it's clear as day.

By definition, modifications that are not classified as "major" require "acceptable" data. "Specified" or "approved" data is required for "major" modifications. Furthermore, it's not as simple as you state. When you install the antenna for example, that portion can become "major" in a hurry. Not usually a big deal though because for non-pressurized puddle jumpers you can use AC 43.13 as "specified" data to install antennas that are classified as "major" modifications.

Neverblue, read up on Maxwell, Faraday and Hertz. You will quickly realize the correct relationship between magnetic fields and electrical fields. Trying to explain it to you is like pissing in the wind.

[NeverBlue]

...because you read up on them during this doesn't make you an expert.

[CID]

...because you read up on them during this doesn't make you an expert.

Finally! A true statement that can't be contested. You are absolutely correct especially when you consider that this is an anonymous forum. As far as you know I could be some crackhead with really good internet search skills and it's right to question statements you read here.

Having said that, I don't know of any other way to validate what I state here. So like I said, check for yourself. Am I full of shit or are you full of shit? You'll only be satisfied with the answer if you check for yourself. If you're looking for authoritative instruction then I'd need to charge you. (not electrically) When you do and you find out that I'm right I still can't declare CID an expert but my comments will be validated.

Let me know if you need any links that might help out.

[lownslow]

[NeverBlue]

I like it...

But I think we're done...

[DonutHole]

You were finished before you even started

[NeverBlue]

...you're a good man nut hole....

[DonutHole]

...you're a good man nut hole....

I would have gone with poopyface doodoohead myself.

[GyvAir]

[NeverBlue]

I would have gone with poopyface doodoohead myself

...ya but NS would've deleted it...

Apparently "poetry" is even derogatory here...

[NeverBlue]

You don't really think I'm right do you?


I don't...