[ICOM] IC-7000 AM Modulation Problem

[w8okn at charter.net]

Absolutely.

- D C *Mac* Macdonald <k2gkk at hotmail.com> wrote: 
> To calculate dB for Voltage or Current
> 
> *                Va
> *  dB = 20 log ------
> *                Vb
> 
> 
>           OR
> 
> 
> *                Ia
> *  dB = 20 log ------
> *                Ib
> 
> 
> To calculate dB for Power
> 
> *                Pa
> *  dB = 10 log ------
> *                Pb
> 
> 
> The result  WILL  be the same for a given
> circuit, assuming linear operation of that
> circuit.
> 
> 73 - Mac, K2GKK/5
> Oklahoma City, OK
> 
> 
> 
> ----Original Message Follows----
> From: <w8okn at charter.net>
> To: ICOM Reflector <icom at mailman.qth.net>
> CC: D C *Mac* Macdonald <k2gkk at hotmail.com>
> Subject: Re: [ICOM] IC-7000 AM Modulation Problem
> Date: Fri, 7 Apr 2006 12:49:20 -0700
> 
> DB is simply a method of comparison based on logarithm
> if I recall my EE math.
> 
> The logarithm of any given number is the exponent of a
> power to which another given invariable number, called
> the base, must be raised in order to produce that given
> number. Thus, let 10 be the base, then 2 is the logarithm
> of 100, because 10^{2} = 100, and 3 is the logarithm of
> 1,000, because 10^{3} = 1,000.
> 
> So, 10 to the 3rd is therefore 2x.  3db gain (or differential
> perhaps might be easier to think about) is a comparison of
> one value to another, in simple terms.   3 dbd would then be
> 2x over a dipole.
> 
> 
> 
> ---- D C *Mac* Macdonald <k2gkk at hotmail.com> wrote:
>   > dB   ARE   dB.  They are identical in absolute quantity.
>   > The difference is that they are derived differently for
>   > voltage, current and power.  The formulas for computing
>   > dB are different, but the absolute difference in dB between
>   > two signals will be the same if calculated with the correct
>   > formula.
>   >
>   > Application of Ohms Law will show that doubling the
>   > applied voltage will also double the current, resulting in
>   > quadrupling of the power.  Figure dB change for any
>   > of these three specific quantities with the correct
>   > formula will give the same result.
>   >
>   >
>   > Mac - K2GKK/5
>   >
>   >
>   >
>   > ----Original Message Follows----
>   > From: C Whitaker <whitaker at pa.net>
>   > Reply-To: ICOM Reflector <icom at mailman.qth.net>
>   > To: ICOM Reflector <icom at mailman.qth.net>
>   > Subject: Re: [ICOM] IC-7000 AM Modulation Problem
>   > Date: Fri, 07 Apr 2006 14:20:06 -0400
>   >
>   > de WB2CPN
>   >
>   > I wonder if we get confused when we're calculating
>   > dB when we don't consider whether it's Voltage dB
>   > or Power dB, there being considerable difference in
>   > the numbers.
>   >
>   > 73  Clete
>   >
>   >
>   >
>   >
>   > ----
>   > Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
>   > Icom Users Net: Sundays, 1700Z, 14.316 MHz
>   > Icom FAQ: http://www.qsl.net/icom/
>   >
>   >
>   > ----
>   > Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
>   > Icom Users Net: Sundays, 1700Z, 14.316 MHz
>   > Icom FAQ: http://www.qsl.net/icom/
> 
> 
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/