Amps
[Top] [All Lists]

Re: [Amps] RMS VS Peak VS Average power and the Bird 43 wattmeter

To: Dennis12Amplify@aol.com, Amps@contesting.com
Subject: Re: [Amps] RMS VS Peak VS Average power and the Bird 43 wattmeter
From: TexasRF@aol.com
Date: Mon, 28 Mar 2005 16:19:03 EST
List-post: <mailto:amps@contesting.com>
 
And, along a similar vein: If a string of 50% duty cycle dots at say 50  
words per minute are transmitted, what should the Bird meter show for power  
output compared to full carrier?
 
73,
Gerald K5GW
 
In a message dated 3/28/2005 3:14:31 P.M. Central Standard Time,  
Dennis12Amplify@aol.com writes:

For the  EXPERTS.....,

I have a question which I believe will combign the two  most  interesting and 
informative threads we have had going here on  the reflector  for quite some 
time.

Why is it that a Bird 43  with a calibrated peak reading kit only  reads 
THREE times the power  for a peak reading of a 100% modulated AM  waveform, 
instead 
of FOUR  times the power as the textbooks all say it  should?

Is it because  the 43 is responding to a Half wave  rectified signal but  
'calibrated' to read as though it was responding to  something  else?

I believe I have an answer, and it is directly related to  both  threads, but 
I was hoping for some open discussion of the  subject to see where  it goes, 
and if it goes in the direction of my  solution or not...

Hint: It is a mathematical relationship between the  average response  of the 
43's analog meter movement and the FCC's  definition of power  output.

Regards,

Dennis  O.



It is surely the best thread we have seen on this reflector  in a long long  
time. Very comprehensive, informative and lots of fun  to  follow.

Thanks to all,
Alek. VK6APK

At 08:33 PM  27/03/2005,  David Kirkby wrote:
>John and Mary Powell wrote in a  different  thread:
>
> >Is there a body of opinion out  there that considers  the above subject 
> has gone on far too  long, or got out of hand. To me  it appears as if 
> academic  intransigence has got in the way of the  Reflector dealing with 
>  it's core business. I noted an earlier plea for  an end to of 
>  this  uninteresting topic, which evolved from a  simple enquiry as  to 
> accuracy of the Bird 43 Wattmeter.
>  >
>  >Cheers
> >John Powell.   ZL1BHQ

_______________________________________________
Amps mailing  list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps




_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>