60 Hertz Tolerance???

[Roy McCammon]

Steven Swift wrote:

I promised a long term plot, but I did a collection of data over
the weekend.

At: http://novatech-instr.com/PDF_files/60hz.pdf

you can see a plot of Seattle City Light's 60Hz power. The data was
taken once per minute with ten readings averaged per point. The 60Hz
was dervied from a transformer runing about 12volts RMS and RC-filtered
to remove spikes. The first 15minutes and last 15minutes were connected
to a "perfect" 60Hz source (GPS derived) to verify stability.

Looks like a longer plot will be interesting.

Steve.

interesting.

Can you integrate it to get accumulated time error?

--
local optimization seldom leads to global optimization

my e-mail address is: rb <my last name> AT ieee DOT org

 

[Steven Swift]

Roy McCammon <rbmccammon@mmm.com> writes:

Can you integrate it to get accumulated time error?

the least squares fit is almost perfect-- so yes, it looks like a smart
servo loop/disciplining circuit could be used. I'll make the week's data
over Christmas available.

Maybe it's time to gin up a "poor man's frequency standard."

--
local optimization seldom leads to global optimization

my e-mail address is: rb <my last name> AT ieee DOT org

--
Steven D. Swift, novatech@eskimo.com, http://www.novatech-instr.com
NOVATECH INSTRUMENTS, INC. P.O. Box 55997
206.301.8986, fax 206.363.4367 Seattle, Washington 98155 USA