[R-390] WWV Time

[rbethman]

George,

Here is your original message requoted:

george stringe wrote:
> OK so here is a test for all the slide rule junkies: I have my Wavetek 
> sig gen all warmed up and my BA Hallicrafter SX-71 tuned to WWV at 
> 2.5Mhz.  When the generator is
> set at  2.50000 Mhz, I am guessing that I get 4 beats/second,  if I 
> set the gen at 2.50001, I get 2 seconds per beat.  So, what is my 
> generator accuracy percentage?
>
> As a second question, which doesn't require a slide rule, how do I 
> reply or keep messages in the same thread?
>
> Cheers,
>
> george
> WG0S
First problem:  "set at  2.50000 Mhz, I am guessing that I get 4 
beats/second"

So we "begin with a GUESS".  Is the second part ANY more accurate? "if I 
set the gen at 2.50001, I get 2 seconds per beat."

I see NO reason to begin even TRYING to get out the slide rule with that 
sort of detail, or lack thereof.

It is precisely WHY my signal generator sat on the bench - WITH my 
oscilloscope - for 72 hours in the Electronics Lab/Repair facility.  
Their frequency references ARE traceable to NIST.  They have to be for 
the research they are doing.

Bob - N0DGN

george stringe wrote:
> With all due respects guys, and I appreciate your input but this 
> really was not an exercise in how to best measure frequency.  Even if 
> I am only 40 miles from the WWV transmitter, I realize it is not 
> perfect, it was just an exercise for all those who have professed a 
> love for the slide rule....and as such, the responses are slim so far 
> ;-)  If I am 5 Hz off in 2.5 million, my calculator says that is 
> .000002 percent.  That can't be correct can it?
>
> george
> WG0S
>
>
>
> Gord Hayward wrote:
>>> Using WWV to ascertain the generator accuracy percentage is VERY 
>>> problematic.
>>
>>
>> It is - the path length is important for absolute time, then there's 
>> the variance of the reflection height.
>> That gives a variable path length as well as a Doppler shift with the 
>> motion.  WWVB is better.
>> Cheers, Gord.

-- 
Bob - NØDGN