@matrix yea terrain will make a huge difference too.

@freemo
Yeah, we have issues receiving TV too even though the height differences in terrain here are tiny.

@matrix presumably TV is on a tall tower. so unless its far away or behind a mountain I'd suspect something else might be up.

@freemo
We have our antenna in the attic and not on the roof. TV works, just with DVBT we didn't get all the multiplexes and now with DVBT2 it occasionally drops out.

@matrix Metal roof or metal siding?

@freemo
No, I think roof is asphalt. It's the terrain, the line to the tower is covered since we live in small valley. A second floor and pole would probably be enough to compensate

@matrix Makes sense. Might not be enough people in range to be worth the cost of a full size tower either.

@matrix @freemo
I have a rooftop antenna and pick up all the high-power ATSC signals from Sacramento just fine, with KUVS-TV occasionally dropping out.
I don't know how it would work with ATSC3, but I haven't a receiver for that yet.

@camedei456

I have a roof top antenna and I can an have sent signals that go around the entire earth and I can hear myself on the receive end by the time it travels full circle back to me (though admittedly this is rare). It is not uncommon however for me to be able to talk both ways over the radio from the USA to europe or father.

@matrix

@freemo @camedei456 @matrix

>I can hear myself on the receive end by the time it travels full circle back to me

How long does this take?

@anonymoose
Very short, it sounds like a subsecond echo.never more than a second unless im bouncing off the moon
@matrix @camedei456

@freemo @matrix @camedei456


>unless im bouncing off the moon

🤯

@matrix @freemo hills are a fuck

@sjw

Its why we RF people always tell people to put their antennas as high as possible. Its all about height.

@matrix

@freemo @matrix No, it's all about line of sight.

@sjw

Sort of. Rf line of sight os not the same as visual line of sight. The horizon is a different effective distance based on frequency to some extent due to refraction.

Higher tower also significantly extends the apparent horizon and will allow it to get past some obstacles.

@matrix

@freemo @matrix Yeah, that's true.
The frequency can also play a big role.
LTE B71 (600 MHz) will act and propagate differently than say LTE B41 (2.5 GHz).

@sjw

Yup, low frequencies will bend around smaller objects like buildings like they arent even there, higher frequencies are blocked trivially by even thin metal obstacles, etc.

Then of course if you get into 10Mhz and below you start getting ionosphere bounce and can go 10,000 km without batting an eye in the right conditions.

@matrix

@freemo @matrix Bending is one thing but you also have to think about how well the signal can penetrate. Especially for use indoors or in dense city settings. E.g. VHF vs. UHF.

@sjw

For sure,, but its also not a simple measure.. higher frequencies have higher penetration depths through nonconductive material like concrete. However they tend to be less penetrating through conductive material like wet ground or metal.

@matrix

@freemo @matrix Yep yep. Radio can be complicated. Hell, planning out a large scale Wi-Fi network is hard enough. Cell network has gotta be 10x harder.

@sjw

Fer shure

@matrix

@sjw @matrix @freemo tell me about it. I'm in 'put your phone in the window to make a call' territory