Limitations of terrestrial UHF

[AhmedGalal]

Firstly I'm sorry if my question is Dump :sad: I'm not a Communication Engineer , I'm production Engineer

What are the geographical limitations of tv reception system of terrestrial UHF ?
What if I used antenna array to incrase gain ? Is that can help me receive far stations ,
Is Analog transmission has more coverage than Digital transmission



Thanks in advance

 

[BradtheRad]

UHF broadcasts have slightly more snow, compared to VHF.

UHF may be processed differently inside the tv, so it may or may not be due to the higher broadcast frequency.

A good antenna does wonders for tv reception. Also the ability to aim it toward the broadcast.

Digital reception is free of snow, however its range is limited compared to analog. My digital tv goes blank if reception is weak. Or perhaps it updates the picture every few seconds.

Analog tv displays some picture from a distant weak station, even if it has a lot of snow.

 

[chuckey]

UHF transmissions are almost line off sight. To receive a distant station the first thing to do is to plot the terrain between it and you. If there is a range of mountains in between you might not get anything. Once you have established that there is line of sight, then the biggest aerial you can afford is the way to go. Elevating your aerial normally boosts the signal and gives a better line of sight.
Analogue v. digital, The transmission power is set to give equal geographic coverage, so its a bit academic.
Frank

 

[biff44]

yep, big antenna, really high up, no mountains in the way, and a booster amp after the antenna.

You MIGHT get some transmission off of sky bounce too, so try pointing antenna up at the sky.

 

[volker@muehlhaus]

sky bounce

What is that - physically?

 

[vfone]

Ionosphere doesn't help UHF signals to get a "sky bounce".

 

[chuckey]

Troposhpereric scatter was (is?) a way of communicating between Caribbean islands with SHF. Way beyond line of sight.
Frank

 

[FvM]

Apparently, troposhpereric scatter works for microwave only.

Some hints about VHF/UHF propagation beyond line of sight utilizing temperature inversion layers, but only temporarily available:
https://en.wikipedia.org/wiki/Non-line-of-sight_propagation#Anomalous_propagation

 

[biff44]

here is a good website that talks about long range tv propagation. unfortunately the calculator only works in the USA/Canada. TV stations further than around 90 miles are listed as troposphere propagation.

**broken link removed**

 

[patel999jay]

you can use the antenna array for UHF antenna if you want higher gain please consider the following link :

**broken link removed**