[amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some calculations)

[i8cvs]

----- Original Message -----
From: <tosca005 at umn.edu>
To: "i8cvs" <domenico.i8cvs at tin.it>
Cc: "Nigel Gunn G8IFF/W8IFF" <nigel at ngunn.net>; "AMSAT-BB"
<amsat-bb at amsat.org>; "Fabio A" <iw8qku at amsat.org>
Sent: Thursday, April 22, 2010 12:04 AM
Subject: Re: [amsat-bb] Re: Arecibo on 432 MHz Moon Bounce (some
calculations)

> Domenico: I suspect that the difference of opinion has to do with the
> difference in punctuation (',' vs. '.') used with large numbers.
>
> In typical American usage,
> 243,902,443 Million Watts = 243,902,443,000,000 watts = 243.9 trillion
> watts
> 243.902 443 million watts = 243,902,443 watts = 243.9 million watts
>
> without the punctuation ->
>
> 243 902 443 million watts = 243 902 443 000 000 watts = almost 244
> trillion watts.
>
> So, I think that if the comma is used as a 3-decade separator and not a
> decimal point, that the original posting was in fact a million times
> overstated. I hope that clarifies it.
>
> If not, then think of it this way.
>
> 400 watts x  0 dB = 400 watts
> 400 watts x 10 dB = 4000 watts = 4 kilowatts
> 400 watts x 20 dB = 40000 watts = 40 kilowatts
> 400 watts x 30 dB = 400000 watts = 400 kilowatts
> 400 watts x 40 dB = 4000000 watts = 4000 kilowatts = 4 megawatts
> 400 watts x 50 dB = 40000000 watts = 40000 kilowatts = 40 megawatts
> 400 watts x 60 dB = 400000000 watts = 400000 kilowatts = 400 megawatts
>
> They were nowhere close to 400 000 000 (400 million) megawatts of ERP.
>
> 400,000,000 million = 400 million million = 400 terawatts
> 400.000.000 million = 400 million         = 400 megawatts
>
> 73 de W0JT
>
Hi , W0JT

I agree with you that the difference of opinion has to do with the
difference in punctuation (',' vs. '.') used respectively in typical
American and
European usage with large numbers so that

400,000,000 million = 400 million million = 400 terawatt in American usage
400.000.000 million = 400 million         = 400 megawatt in European usage
like in Germany France and Italy

Tanks and

73" de

i8CVS Domenico