[AMRadio] PEP for AM


Gary Schafer garyschafer at comcast.net
Sat Dec 30 14:20:56 EST 2006



> >>
> >> P E P (AM)
> >> % Modulation = (( PEP - PC) / PC) *100%
> >>
> >> Example:
> >> Carrier Power PC = 100 W, PEP = 400 W.
> >>
> >> Determine % Modulation
> >> M% = (( 400 - 100) / 100) *100% = ((20-10) / 10) *100% = 100%


> > Hmmm, let's see, 400 watts -100 watts = 300 watts. Divided by 100 watts
> =
> > 3.
> > Times 100% = 300% modulation..
> >
> > I think they forgot the square root of the powers in the formula.
> 
> Looks like that may add to the misconception.  But I'm not sure they left
> out the square root symbol.  Could that be the reason for the double
> parentheses on the left?  Since most word processing programs do not have
> easy access to mathematical symbols, and e-mail programs may not have them
> at all, a special set of symbols has evolved for mathematical expressions.
> I am not totally familiar with them, and I sometimes get totally lost when
> trying to interpret mathematical expressions posted over the internet.
> 
> Isn't this what the formula is supposed to look like?  (the problem is
> that
> it may not display correctly if your e-mail reader does not support
> Unicode).
> 
>                                ____      ___        ___
>  % Modulation = ( vPEP -  vPC  ) / (vPC) *100%
> 
> Evidently "they" think that so few people would have a use for
> mathematical
> formulae that maths symbols are not included in the default character set.
> Just like the ricebox manufacturers who no longer include monitor scopes
> in
> their appliance product line.
> 
> Don k4kyv


This is how it should be. 

 % Modulation = (( vPEP -  vPC) / vPC) *100%

They had the parenthesis correct but didn't have the square root signs. You
need the double parenthesis at the front as there are two opposite ones
following. They must all balance. You perform the functions within the inner
set first then do what is in the next set, then do what is outside last.

I cut and pasted your square root symbols for this. Can someone tell me how
to do square root symbols on a regular keyboard?

73
Gary  K4FMX





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