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Physics/frequency measurement

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Question
Dear Sir,
In the early stages of telecommunications and electronics, how did they measure the high frequency?, for example, how did  they count frequencies of an oscillator circuit  above 1 Khz?. Even if the frequency would be 100 Hz,  I canīt imagine any electro mechanic device to do this.

Answer
Hello miguel,

See additional info added at the end.

I haven't been able to find a definite answer for your question. Perhaps a way to measure frequency would have had to wait for an early oscilloscope. Then they would have to count pulses on the waveform within the horizontal grid that represents 1 second (or 1 s/10 or 1 s/100 etc.). If so, accurate timing the rate of the horizontal sweep would probably have involved a quartz crystal.

Alternative methods that I have no experience with involve an absorption wavemeter
http://en.wikipedia.org/wiki/Absorption_wavemeter
or a wavemeter based on a resonant cavity
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5299191&url=http%3A%2F%2Fi

I have submitted a request to the website
http://www.tf.nist.gov/general/museum/847history.htm
for help on your question. If I get a reply with applicable information, I will edit my reply to you. Allexperts.com will then notify you to check my answer again.

I hope this helps,
Steve

P.S.

The request to the nist website yielded images of 6 pages from a book that they had. The 6 jpg files are in the album that the link will take you to.
http://s131.photobucket.com/user/tjsail/slideshow/wwv

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Steve Johnson

Expertise

I would be delighted to help with questions up through the first year of college Physics. Particularly Electricity, Electronics and Newtonian Mechanics (motion, acceleration etc.). I decline questions on relativity and Atomic Physics. I also could discuss the Space Shuttle and space flight in general.

Experience

I have a BS in Physics and an MS in Electrical Engineering. I am retired now. My professional career was in Electrical Engineering with considerable time spent working with accelerometers, gyroscopes and flight dynamics (Physics related topics) while working on the Space Shuttle. I gave formal classroom lessons to technical co-workers periodically over a several year period.

Education/Credentials
BS Physics, North Dakota State University
MS Electrical Engineering, North Dakota State University

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