[Elecraft] K3 dumb Q about PPM, less dumb one about NB

[Garry Shapiro]

mHz may or may not be widely used in ham radio, but it is widely used 
everywhere else and, IMHO, incorrectly. At least one place in my ham 
life where it is used is in the Low Band Monitor published by K0CS.

Garry, NI6T

On 4/2/2010 3:53 AM, Jim Wiley wrote:
>
> I suspect the original writer is being confused with the correct
> designation of the units involved in the query.  One PPM  is equivalent
> to 1 hertz per megahertz.  Stability specifications for amateur radio
> equipment are frequently stated in reference to 1 megahertz.  In such a
> case, 1 PPM at 10 MHz works out to 10 hertz.
>
>
> The units described in the original question are stated as mHz,
> (millihertz), or 1/1000 of a hertz.  Megahertz, or 1 million hertz,  is
> more correctly annotated as MHz.   A value stated in millihertz is
> uncommon in amateur radio circles.  It is perfectly true that a
> millihertz is a valid unit, it's just not often seen.  And, as far as I
> know, has never been used, either in an advertisement or a user manual,
> to express the basic frequency stability of a piece of ham gear.
>
>
> - Jim, KL7CC
>
>
> David Woolley wrote:
>    
>> 1ppm relative to 10mHz is 10nHz (unless you are a PC salesman).  There
>> are aspects of amateur radio in which mHz are a useful unit.
>>
>> lstavenhagen wrote:
>>
>>      
>>> Just refreshing my 6th grade education here: 1 ppm variation at 10 mhz would
>>> be +/- 10 hz correct? I calibrated my K3 ref. osc. again yesterday (against
>>>
>>>        
>>
>>
>>
>>      
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