Low VHF interference

[rabbit73]

Rabbit73: How do you calculate the length of a folded dipole using 14AWG? Thank you.

It would be pretty much the same as with twinlead.

Channel 2 is 54 to 60 MHz; center freq is 57 MHz
5540 divided by 57 = 97 inches

 

[freeisforme]

It would be pretty much the same as with twinlead.

Channel 2 is 54 to 60 MHz; center freq is 57 MHz
5540 divided by 57 = 97 inches

Thats easy math.
Where does 5540 come from? Thank You.

 

[rabbit73]

Thats easy math.
Where does 5540 come from? Thank You.

Radio waves travel at the same speed as light waves, which is a constant called c:
The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is defined as 299792458 metres per second (approximately 300000 km/s, or 186000 mi/s).

The length of a halfwave dipole can be calculated in meters, feet or inches.
Mathematical Applications

λ (lambda) = c/freq

The length of the antenna is less than the free space length because of the "end effect."
Dipole Antenna Length: Calculation & Formula » Electronics Notes

The end effect is larger for VHF and UHF antennas because of the length to diameter ratio. Using the inches formula and the correction factor of 0.94:

5905 x 0.94 = 5550

Empirical tests show that 5540 works best in practical TV antennas:

5540 divided by 57 MHz = 97.2 inches

 

[navychop]

And I thought I understood this.
Thanks.

 

[freeisforme]

sorry for the long delay i didnt get email. if i did i deleted by mistake.

 

[freeisforme]

Radio waves travel at the same speed as light waves, which is a constant called c:
The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is defined as 299792458 metres per second (approximately 300000 km/s, or 186000 mi/s).

The length of a halfwave dipole can be calculated in meters, feet or inches.
Mathematical Applications

λ (lambda) = c/freq

The length of the antenna is less than the free space length because of the "end effect."
Dipole Antenna Length: Calculation & Formula » Electronics Notes

The end effect is larger for VHF and UHF antennas because of the length to diameter ratio. Using the inches formula and the correction factor of 0.94:

5905 x 0.94 = 5550

Empirical tests show that 5540 works best in practical TV antennas:

5540 divided by 57 MHz = 97.2 inches

Im good at math but, WOW. Good read.

 

[freeisforme]

I was waiting for channel master jointenna to be in stock, Came in stock Thursday, but they didnt update the LTE filter therefore i didn't buy it. When they update it, i will buy it. RF 2 does "come in, not watchable" more often then the twin lead. For now i may try different 2-ways and seen if one is better then the other. Thanks Rabbit73.