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broadcast tv signal , can you have too much ?

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https://sigforum.com/eve/forums/a/tpc/f/320601935/m/2640024424

May 19, 2017, 07:45 AM
ensigmatic
broadcast tv signal , can you have too much ?
quote:
Originally posted by JALLEN:
quote:
Originally posted by ensigmatic:
Yes, it is possible to have too much signal. Will saturate the receiver's front end and cause distortion (analog) or disruption (digital).

What would the signal level be say, 1 mile from the transmitter antenna?

Depends on a wide variety of factors, such as transmitter power, antenna design, geographic characteristics, etc.

Not close enough to overload a receiver front-end, though.


"America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe
"If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher
May 19, 2017, 10:04 AM
cne32507
bendable could try a mast mounted bowtie pointed NW and it might pick up the SE stations also. If it didn't get the NW stations, he could redirect it SE and add a better antenna for the NW stations.
May 19, 2017, 11:24 AM
bendable
quote:
Dd you check the second link I posted?


yes sir

altitudes of antennas
Quad cities 743 feet w/ 300 ft tower
walker ( cedar rapids ) 830 feet with 250 ft tower.

bennett, iowa 778 ft w/ 15 ft antenna




Safety, Situational Awareness and proficiency.


Neck Ties, Hats and ammo brass, Never ,ever touch'em w/o asking first
September 24, 2018, 10:31 PM
radioman
quote:
Originally posted by ensigmatic:
quote:
Originally posted by JALLEN:
quote:
Originally posted by ensigmatic:
Yes, it is possible to have too much signal. Will saturate the receiver's front end and cause distortion (analog) or disruption (digital).

What would the signal level be say, 1 mile from the transmitter antenna?

Depends on a wide variety of factors, such as transmitter power, antenna design, geographic characteristics, etc.

Not close enough to overload a receiver front-end, though.


here's a real world example of this 21.87 KW ERP station: https://nocable.org/browse-sta...ign/kptv-portland-or

Assume your receiver log periodic on the roof has about 6 db of gain on CH 12, and that's being generous. Ignore cable losses. Assume LOS (line of sight), but your path loss will likely be greater since you may not be LOS.

Use this equation: https://www.pasternack.com/t-calculator-friis.aspx
use 0 db for transmitter antenna gain since we already know ERP. Enter the 21870 watts
Channel 12 is 207 MHz.

Get an answer of Received Power = 0.0004465 W at one mile. Note what happens at 10 miles.

Play with the numbers to get a feel for things.

Some of the UHF stations are a million watts ERP Eek But the MHz is higher. So try that trade off.


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Let's Go Brandon!