SlideShare une entreprise Scribd logo
1  sur  11
Télécharger pour lire hors ligne
An antenna is a significant part of any two way radio
system. No radio can outperform its antenna. Many
     times users have been able to improve the
performance of a communications system merely by
              improving the antennas.




antenna
The AM radio waves are below 2 MHz; these signals follow the
Earth's curvature because they are reflected off the
atmosphere Therefore AM radio signals in low-noise environments
can be received by radios that are way below the horizon hundreds
of miles away Whereas two-way radios usually fall in the frequency
range of 150MHz to 900MHz; these frequencies antenna travel in
straight lines
Radio waves can be reflected, or bounce off surfaces so the straight
line between radios, may not always be so straight Anyway as a
general rule these waves cannot travel over the horizon or behind
solid obstacles Because of this reason, you have to factor in
antenna height as well for sending signals farther
Antenna gain is measured in decibels, or dB A 0 dB antenna
(sometimes called a "unity" gain antenna), is an antenna with no gain
 More gain on an antenna will, usually but not always, give you more
range
An-Antenna-Is-A-Significant-Part-Of-Any-Two-Way-Ra10
Generally, to get more gain you need a bigger antenna A simple
"quarter wave" (0 dB, or unity gain) antenna for VHF is about 18
inches long A 3 dB antenna for the same frequency would be about
4 feet long, while a 5 dB antenna is maybe 8 feet
For UHF, a quarter wave is six inches, and a 5 dB about 2 feet
Lower the frequency, longer the antenna If you're using the 3
inch stubbies on a UHF portable, you might see a difference going to
the six inch rubber duck
Theoretically the longer antenna is better Directional antennas
achieve much of their gain by rejecting pick-up from certain areas,
such as the sides and rear in the case of a log periodic (the typical
shark fin is an example of a log periodic antenna) A higher level
signal helps improve the signal to noise ratio by overcoming the
noise induced in an antenna cable, but a signal that is too high can
cause problems at the receiver
This is why antenna amplifiers typically have jumper settings to
apply the proper amount of gain needed to compensate for loss in a
cable of particular type and length There are other factors that
affect the range of a two-way radio too such as weather, exact
frequency used, and obstructions
The radio's power output has a factor too
antenna

Contenu connexe

En vedette

Trends In Paid Search: Navigating The Digital Landscape In 2024
Trends In Paid Search: Navigating The Digital Landscape In 2024Trends In Paid Search: Navigating The Digital Landscape In 2024
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
 
5 Public speaking tips from TED - Visualized summary
5 Public speaking tips from TED - Visualized summary5 Public speaking tips from TED - Visualized summary
5 Public speaking tips from TED - Visualized summarySpeakerHub
 
ChatGPT and the Future of Work - Clark Boyd
ChatGPT and the Future of Work - Clark Boyd ChatGPT and the Future of Work - Clark Boyd
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
 
Getting into the tech field. what next
Getting into the tech field. what next Getting into the tech field. what next
Getting into the tech field. what next Tessa Mero
 
Google's Just Not That Into You: Understanding Core Updates & Search Intent
Google's Just Not That Into You: Understanding Core Updates & Search IntentGoogle's Just Not That Into You: Understanding Core Updates & Search Intent
Google's Just Not That Into You: Understanding Core Updates & Search IntentLily Ray
 
Time Management & Productivity - Best Practices
Time Management & Productivity -  Best PracticesTime Management & Productivity -  Best Practices
Time Management & Productivity - Best PracticesVit Horky
 
The six step guide to practical project management
The six step guide to practical project managementThe six step guide to practical project management
The six step guide to practical project managementMindGenius
 
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...RachelPearson36
 
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Applitools
 
12 Ways to Increase Your Influence at Work
12 Ways to Increase Your Influence at Work12 Ways to Increase Your Influence at Work
12 Ways to Increase Your Influence at WorkGetSmarter
 
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...DevGAMM Conference
 
Barbie - Brand Strategy Presentation
Barbie - Brand Strategy PresentationBarbie - Brand Strategy Presentation
Barbie - Brand Strategy PresentationErica Santiago
 
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them well
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them wellGood Stuff Happens in 1:1 Meetings: Why you need them and how to do them well
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them wellSaba Software
 
Introduction to C Programming Language
Introduction to C Programming LanguageIntroduction to C Programming Language
Introduction to C Programming LanguageSimplilearn
 
The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...
The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...
The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...Palo Alto Software
 
9 Tips for a Work-free Vacation
9 Tips for a Work-free Vacation9 Tips for a Work-free Vacation
9 Tips for a Work-free VacationWeekdone.com
 

En vedette (20)

Trends In Paid Search: Navigating The Digital Landscape In 2024
Trends In Paid Search: Navigating The Digital Landscape In 2024Trends In Paid Search: Navigating The Digital Landscape In 2024
Trends In Paid Search: Navigating The Digital Landscape In 2024
 
5 Public speaking tips from TED - Visualized summary
5 Public speaking tips from TED - Visualized summary5 Public speaking tips from TED - Visualized summary
5 Public speaking tips from TED - Visualized summary
 
ChatGPT and the Future of Work - Clark Boyd
ChatGPT and the Future of Work - Clark Boyd ChatGPT and the Future of Work - Clark Boyd
ChatGPT and the Future of Work - Clark Boyd
 
Getting into the tech field. what next
Getting into the tech field. what next Getting into the tech field. what next
Getting into the tech field. what next
 
Google's Just Not That Into You: Understanding Core Updates & Search Intent
Google's Just Not That Into You: Understanding Core Updates & Search IntentGoogle's Just Not That Into You: Understanding Core Updates & Search Intent
Google's Just Not That Into You: Understanding Core Updates & Search Intent
 
How to have difficult conversations
How to have difficult conversations How to have difficult conversations
How to have difficult conversations
 
Introduction to Data Science
Introduction to Data ScienceIntroduction to Data Science
Introduction to Data Science
 
Time Management & Productivity - Best Practices
Time Management & Productivity -  Best PracticesTime Management & Productivity -  Best Practices
Time Management & Productivity - Best Practices
 
The six step guide to practical project management
The six step guide to practical project managementThe six step guide to practical project management
The six step guide to practical project management
 
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
 
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...
 
12 Ways to Increase Your Influence at Work
12 Ways to Increase Your Influence at Work12 Ways to Increase Your Influence at Work
12 Ways to Increase Your Influence at Work
 
ChatGPT webinar slides
ChatGPT webinar slidesChatGPT webinar slides
ChatGPT webinar slides
 
More than Just Lines on a Map: Best Practices for U.S Bike Routes
More than Just Lines on a Map: Best Practices for U.S Bike RoutesMore than Just Lines on a Map: Best Practices for U.S Bike Routes
More than Just Lines on a Map: Best Practices for U.S Bike Routes
 
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...
Ride the Storm: Navigating Through Unstable Periods / Katerina Rudko (Belka G...
 
Barbie - Brand Strategy Presentation
Barbie - Brand Strategy PresentationBarbie - Brand Strategy Presentation
Barbie - Brand Strategy Presentation
 
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them well
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them wellGood Stuff Happens in 1:1 Meetings: Why you need them and how to do them well
Good Stuff Happens in 1:1 Meetings: Why you need them and how to do them well
 
Introduction to C Programming Language
Introduction to C Programming LanguageIntroduction to C Programming Language
Introduction to C Programming Language
 
The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...
The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...
The Pixar Way: 37 Quotes on Developing and Maintaining a Creative Company (fr...
 
9 Tips for a Work-free Vacation
9 Tips for a Work-free Vacation9 Tips for a Work-free Vacation
9 Tips for a Work-free Vacation
 

An-Antenna-Is-A-Significant-Part-Of-Any-Two-Way-Ra10

  • 1. An antenna is a significant part of any two way radio system. No radio can outperform its antenna. Many times users have been able to improve the performance of a communications system merely by improving the antennas. antenna
  • 2. The AM radio waves are below 2 MHz; these signals follow the Earth's curvature because they are reflected off the atmosphere Therefore AM radio signals in low-noise environments can be received by radios that are way below the horizon hundreds of miles away Whereas two-way radios usually fall in the frequency range of 150MHz to 900MHz; these frequencies antenna travel in straight lines
  • 3. Radio waves can be reflected, or bounce off surfaces so the straight line between radios, may not always be so straight Anyway as a general rule these waves cannot travel over the horizon or behind solid obstacles Because of this reason, you have to factor in antenna height as well for sending signals farther
  • 4. Antenna gain is measured in decibels, or dB A 0 dB antenna (sometimes called a "unity" gain antenna), is an antenna with no gain More gain on an antenna will, usually but not always, give you more range
  • 6. Generally, to get more gain you need a bigger antenna A simple "quarter wave" (0 dB, or unity gain) antenna for VHF is about 18 inches long A 3 dB antenna for the same frequency would be about 4 feet long, while a 5 dB antenna is maybe 8 feet
  • 7. For UHF, a quarter wave is six inches, and a 5 dB about 2 feet Lower the frequency, longer the antenna If you're using the 3 inch stubbies on a UHF portable, you might see a difference going to the six inch rubber duck
  • 8. Theoretically the longer antenna is better Directional antennas achieve much of their gain by rejecting pick-up from certain areas, such as the sides and rear in the case of a log periodic (the typical shark fin is an example of a log periodic antenna) A higher level signal helps improve the signal to noise ratio by overcoming the noise induced in an antenna cable, but a signal that is too high can cause problems at the receiver
  • 9. This is why antenna amplifiers typically have jumper settings to apply the proper amount of gain needed to compensate for loss in a cable of particular type and length There are other factors that affect the range of a two-way radio too such as weather, exact frequency used, and obstructions
  • 10. The radio's power output has a factor too