µwave Comm.

[KeepItSimpleStupid]

We had an old 400mhz radar on my (USS Okinawa) ship that technically was listed as microwave radiation on the

mHz = milliHertz? MHz = megahertz, Hz is capitalized because it's someone's name. mhz = ? I have no idea.

 

[nsaspook]

mHz = milliHertz? MHz = megahertz, Hz is capitalized because it's someone's name. mhz = ? I have no idea.

Learn something new everyday... Yes, it's 0.4 kMc.

 

[KeepItSimpleStupid]

Cell phone booster: https://www.ubersignal.com/cell-phone-repeater

For WIFI, you can probably use a repeater. I use one at home. It actually sits about 5 feet from where i had trouble receiving a signal and I can have WIFI outside. A straight-line path would show way too many obstructions. 7 feet of earth and a 6" cement pad and a cinderblock wall for starters.

There are a few frequencies reserved in various bands that are unlicensed. e.g. the frequency that a microwave cooks at and say 14.56 MHz. I maintained/used an 1000 W "sputtering" transmitter at 14.56 MHz. This technology could be used to put the metal on a potato chip bag. It comes in 2 flavors DC sputtering and RF sputtering. DC is used for metals and RF for insulators and semiconductors. We used it for ZnO and ITO which are metallic transparent contacts. Mo was are primary DC target. You can actually sputter glass or place a thin coating of glass on things. There is no "information" transmitted at these frequencies.

 

[KeepItSimpleStupid]

0.4 kMc is definitely "old school" . I have an old AM radio marked that way kc or kcps , I'd have to look. But i had a wierd 3-band tube car radio by Blaupunkt that was marked in wavelength for AM/FM and SW. So, there isn't a 90.1 on the FM band.