Question on micro waves ???

[Quasar44]

I know MW can vary in size but do they normally pass through walls
Many times I get a signal through concrete walls then other times I don’t

My guess is it passes through walls, but only has very limited range as in WiFi signals

 

[Mushroom]

I know MW can vary in size but do they normally pass through walls

Depends on the power used.

Most WiFi routers operate at around 25-45 watts. Most microwave ovens operate at around 1,000 watts. At peak power, a PATRIOT fire control RADAR runs at around 200,000 watts. And yes, I have been radiated by one and you can unquestionably feel the side of your body facing the RADAR get much hotter than the side of your body pointed away from the RADAR.

 

[EvilEyeFleegle]

Depends on the power used.

Most WiFi routers operate at around 25-45 watts. Most microwave ovens operate at around 1,000 watts. At peak power, a PATRIOT fire control RADAR runs at around 200,000 watts. And yes, I have been radiated by one and you can unquestionably feel the side of your body facing the RADAR get much hotter than the side of your body pointed away from the RADAR.

Back in the day, aboard ship we liked to amuse ourselves by cycling the fire control radar..1 time--while the seagulls were perched in its line of emission. This was popular around 7am--Officer's Call. The one cycle would kill the birds, appearing to cook them from the inside out. They would plummet 150 feet to explode on the deck, showering the officers with guts.

Good times~

Edited..thanks Crepitus

 

[Gabe Lackmann]

I know MW can vary in size but do they normally pass through walls
Many times I get a signal through concrete walls then other times I don’t

My guess is it passes through walls, but only has very limited range as in WiFi signals

Why Does Wi-Fi Use the Same Frequency as Microwaves?

When you start your microwave, do you lose Wi-Fi signal on a nearby device? Wi-Fi and Microwaves both operate on a similar frequency, which can lead to interference. But why? And if that’s the case why doesn’t Wi-Fi cook you?

www.howtogeek.com

 

[Crepitus]

Back in the day, aboard ship we liked to amuse ourselves by cycling the fire control radar..1 time--while the seagulls were perched in its line of emission. This was popular around 7am--Officer's Call. The one cycle would kill the birds, cooking them from the inside out. They would plummet 150 feet to explode on the deck, showering the officers with guts.

Good times~

That would take millions of watts + microwaves cook from the outside in just like any other cooking method.

 

[cnm]

microwaves cook from the outside in just like any other cooking method.

Yes. It's not like the centre of potatoes are cooked and the outside raw.

 

[EvilEyeFleegle]

That would take millions of watts + microwaves cook from the outside in just like any other cooking method.

Yes..from the outside in...however, the liquid molecules are excited first..and release their energy by boiling, the appearance was that the birds were untouched on the outside--although after the falls...was rather hard to tell. At a distance of 18" or less it did not take..millions of watts...6 to 8KW was more than enough. Not saying that the birds were cooked through or anything..just enough to kill them dead. Probably embolism or something.
But yeah...the inside out thing is a myth, for sure.

Post edited..thanks.

 

[Crepitus]

Yes. It's not like the centre of potatoes are cooked and the outside raw.

People get that idea because it will cook through things that don't absorb microwaves like plastic packaging, glass cookware, and eggshells.

 

[Crepitus]

Yes..from the outside in...however, the liquid molecules are excited first..and release their energy by boiling, the appearance was that the birds were untouched on the outside--although after the falls...was rather hard to tell. At a distance of 18" or less it did not take..millions of watts...6 to 8KW was more than enough. Not saying that the birds were cooked through or anything..just enough to kill them dead. Probably embolism or something.
But yeah...the inside out thing is a myth, for sure.

Post edited..thanks.

A previous post points out that standing in front of 200,000 watts makes one side of your body warm. 8,000 watts just won't cut it. If it could do what you claim it would leave a line of live steam every time it pulsed just from atmospheric moisture.

 

[ProfessorHawthorne]

I know MW can vary in size but do they normally pass through walls
Many times I get a signal through concrete walls then other times I don’t

My guess is it passes through walls, but only has very limited range as in WiFi signals

Depends on the power used.

Most WiFi routers operate at around 25-45 watts. Most microwave ovens operate at around 1,000 watts. At peak power, a PATRIOT fire control RADAR runs at around 200,000 watts. And yes, I have been radiated by one and you can unquestionably feel the side of your body facing the RADAR get much hotter than the side of your body pointed away from the RADAR.

Microwave is a bit of a generic term. The real factor that determines the signal's properties is the wavelength. As the frequency goes up, the wavelength gets shorter. The new 5G cellular is based on using some sub-6GHZ frequencies that are in use now for existing 4G LTE service. The "real" hotdog super fast speeds will come with the use of what's called the "mm band" or millimeter band - referring to the wavelengths at 28GHZ and up. These short wavelengths do not penetrate walls and have limited range because they bounce off just about everything. Hope this helps.

Now, to Mushroom.
Wi-Fi routers do NOT operate at 25-45 watts. They operate as Part 15 unlicensed devices and are limited usually to less than 0.5 watts or 500mW. Usually the router will operate with around 100mW unless it has been hacked. The idea of 45 Watts of 5GHZ energy circulating in a home is downright scary. It's fine, I guess, if you have tumors you want to shrink, but I wouldn't want to spend much time in close proximity to it. Also, with the waterfall conversion several years ago upgrading the Patriot A/D converters from 10bit to 12bit, RADAR power could actually be decreased, if necessary, while still achieving greater resolution and detail of the target. The company I retired from produced several electronic components/subsystems for Raytheon and the PMDS.
Cheers

 

[Mushroom]

A previous post points out that standing in front of 200,000 watts makes one side of your body warm. 8,000 watts just won't cut it. If it could do what you claim it would leave a line of live steam every time it pulsed just from atmospheric moisture.

And the PATRIOT RADAR only cycled up that high when firing. It was one of the most powerful mobile RADAR systems made, and had a massive power plant composed of two 150 watt diesel generators. That like most generators in the system, at that time would ramp up beyond the "red line" to give the power needed for firing.

But that is only during firing, it was still a beast though. They are operated almost daily around Fort Bliss in El Paso, Texas. And if they were as deadly as claimed, the landscape would be littered with dead wildlife. The safe range is actually only around 100 meters from the system when it is radiating. And there is a procedure the RADAR crew is supposed to follow when they start radiating. Including sounding a horn to warn all downrange of the unit to stay clear.

My worst exposure came in my final year in the field with the system. I was walking back from my launcher, and noticed I was getting warm. At around 70 meters I made a sudden turn, and walked until I was out of the RADAR's cone. And I got to the control van just as the Chief Warrant Officer came up to chew me out. I asked why the warning horn had not sounded, and at about the same time somebody from another crew asked the same thing, he had from from a launcher on the other side.

Turns out it was a new crew being trained, and they had indeed forgot to sound the warning. Or turn on the light that is a visual cue for the same thing. But it is perfectly safe to walk in front of one, it will not kill you or really harm you in any way. And it really is just an offshoot of the AN/SPY-1 RADAR that the AEGIS Navy system uses.

 

[HenryBHough]

Getting back to the concrete wall.....

Plain concrete has a tiny metallic content so can pose an obstacle to very low-powered microwave devices.

Concrete with re-bar inside....common with concrete blocks....is more of an obstacle. At microwave frequencies generally not better.

Poured concrete with steel mesh inside is a more effective barrier. It's somewhat more complex depending upon the frequency of the microwaves vs. the "tightness" of the mesh; the metal used and whether the mesh is effectively connected to (Earth) ground.

Many of the buildings I work in have grounded copper mesh inside the walls (generally under the exterior siding) to keep radio-frequency energy OUT. For example, when the buildings are very close to high-powered AM radio antennas.