[time-nuts] cheap 5V OCXO in 14DIP has about 1E-9 drift per day

[Chuck Harris]

Magnus Danielson wrote:
> On 04/09/2011 11:57 PM, Chuck Harris wrote:
>> Hi Brooke,
>>
>> My recollection of first seeing the 4K7 style of marking was
>> around about the time computers started being used for inventory
>> control... 1970's. It was only the European companies that
>> were doing it. It eliminated the confusion caused by the US/Eu
>> "." and "," decimal points. It also is less prone to losing the
>> "." on a component, or PCB mask.
>>
>> I acknowledge all of that. But as far as I know, it has never
>> been used for time and frequency. That is what I am concerned
>> about. It seriously degrades the readability of the emails that
>> are formatted that way.
>
> For components yes, for other usage... no.
>
> Unit must be know for component type.
>
> I see it as a short-hand being practical and avoids the . or , issues
> (confusion and loosing them).
>
> Outside of the component value situation I think SI should be applied.
> I prefer 1 nF over 0,001 uF, 1000 pF or 1000 uuF. Also, 10 mF should be
> used over 10000 uF. It's not that hard to do right...
>
> Cheers,
> Magnus

My general feeling is if a 9th grader couldn't figure out what the meaning
of the text is without asking someone, it might be a bad idea.

Any 9th grader will understand 4.7 kohms, or 9.6 pf to be a quantity of something
called a kohm, or a pf.

What will they think when they see 4K7 ohms, or 9P6  farads?

Or back to the original item, 10M000 Hz?

SI is what we should be using for all of this correspondence, not some hacked
up system that manufacturers devised for marking components.  You wouldn't
consider telling us to use a yellow violet red and a white blue gold as a
low pass filter.  Why tell us to use a 10M000 oscillator?

-Chuck Harris