Formula....?

[pwdrive]

It's common knowledge that my maths aint to good but here goes (also posted on UKVRR):

Known...(antenna length) l = 24.4 metres, Lambda (wavelength) = 300 metres.

Formula in book: 2*pi*l/Lambda.

My calc: = 0.511.

In the book it shows....2*pi*l/Lambda = 29.3 degrees.

I can figure out 29.3 degrees by another route, but not by the above formula.

Maths not to good with me but can someone explain?

Lawrence.

[ppppenguin]

29.3 degrees is equal to .511 radians.

I'm not familiar with the formula you quote but if you're using radians there's not usually 2*PI in the formula. There are 2*Pi radians in a full circle.

[pwdrive]

29.3 degrees is equal to .511 radians.

I'm not familiar with the formula you quote but if you're using radians there's not usually 2*PI in the formula. There are 2*Pi radians in a full circle.

Cheers, I thought you might be first

I'll have to look up what radians is again......If I was writing the book I would have written the answer as "0.511 radians which equals 29.3 degrees"

Not very good, I would expect a bit better from RDH4.....Such as Zo..Zi seems to be mixed up? Can you confirm either way? Link below...book page 903, starts near the bottom (Example of Calculations)

http://frank.yueksel.org/other/RCA/Radio...-Lines.pdf

Lawrence.

[ppppenguin]

Radians exist naturally. It's the arc of a circle where the radius equals the circumference. There's a nice little animation here:
https://en.wikipedia.org/wiki/Radian

Degrees are a human idea, an arbitrary division of a circle into 360 of them. Lots of formulae work better in radians and radians per second (aka angular frequency, symbol is lower case omega, equal to 2 *PI *f)

[pwdrive]

GJ over on UKVRR has confirmed the Zo Zi error in the RDH4 text.

Lawrence.