[R-390] WWV Frequency Standard

[rbethman]

Roger,

I never said "our" hobby needed the level of accuracy that Uncle Sam 
maintains.

I was referring to a "very"minuscule difference between a signal 
generator output, the counter reading it, and it's "zero beating" in a 
receiver.

In THAT context, the use of WWV was problematic, ESPECIALLY at 2.5MC.  
It would be preferable to use 10MC signals.  This was what 
manufacturer's of old boatanchors built-in to their equipment for 
"calibration" of the internal crystal calibrator.

This is MORE than adequate for Amateur Radio use.

Uncle Sam has needs that FAR exceed what "WE" require.

Bob - N0DGN

Flowertime01 at wmconnect.com wrote:
> Fellows,
>
> There is a difference between absolute time and frequency.
>
> Count time ticks from WWV and time ticks from your local standard.
>
> After six months or so review the difference on your two counters.
> Then adjust your local time standard up or down a bit.
>
> You frequency standard is within one 1 second time tick over six months.
> I suggest that is close enough for government work.
>
> In 1975 in Okinawa we would trigger two counters and let it run 24 hours.
> We expected zero difference. We perforned this test as a monthly 
> maintenance procedure. This was just for a frequency standard.
>
> For time we used a dual trace scope and an off set time delay number 
> provided by the military to us. There was a document with lots of 
> locations and expected time delay.
>
> Again we measured the delay with a dual trace scope and averaged the 
> delay over lots of time (weeks). The "clock" had an offset in it. The 
> frequency standard tick edge was any where it wanted to be. The clock 
> would let us have any number of steps up to 1,000,000 between the 
> frequency edge and the time edge. Then you could set the time display 
> to tick any second from the time edge.
>
> In the Army with lots of techs working 24 X 7 you could put 6 or 8 
> guys on the job of guarding the "maintenance procedure" for 3 or 4 
> days each month. You did not watch it all shift but you set up the 
> procedure and passed it from shift to shift.
>
> In the Army you just did not clown around with some activity going on. 
> Hundreds of guys and girls worked in the radio rooms and just left 
> things alone for ever and ever.
>
>
> You can have a standard in your shop that is closer than a RCH.
>
> And then I ask you what for?
>
> The American Military has run planet wide RF communications and 
> reportedly off planet communications with R390's, TS505s, TS352s, TEK 
> 505s, and AN/URM25's since the 1950s.
>
> What are you doing in your hobby that needs better resolution than 
> what you can get with that equipment?
>
> You cannot prepare kebelsa sausage with better resolution.
>
> Roger AI4NI
>
>
>
>
> /
> /
>
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-- 
Bob - NØDGN