transmitting clock signal

how far? how fast? how much?

martin

Hello

100 m 1 Mhz 100 $ mart> >

Ofcourse. DSC, Digital Sattelite Communication, is simply the same radio waves used for analog radio recievers your car radio uses. However instead of waves with an analog makeup, the waves have a square wave makeup, 100% comparable to your clock signal. What you will be doing is transmitting digital waves.

The maximum clock frequency is really all dependent on the recieve and transmitter ICs you are using. You could get up to gigabit rates, if you have the time to research.

In message , dated Thu, 31 Aug 2006, martin griffith writes

There is no point in asking questions; the OP clearly doesn't understand anything.

You don't need to send square waves; if you did, WWV would send them! You send sine waves, and square them up with a limiter at the receiving end.

You just want to send, and receive, an accurate frequency. So you can't use a superhet receiver if you use the carrier as the 'accurate frequency'. But that gets you the highest possible sending frequency, and current techniques will let you go beyond 100 GHz, which is likely to be too fast for any clock you want.

The answer to 'how far' is 'to the boundaries of the Universe';

The answer to 'how fast' is 'around 300 000 km/s';

The answer to 'how much' is ' about 50% of what it costs to do a good job, as usual'.

--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
2006 is YMMVI- Your mileage may vary immensely.

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

please dont top post I would suggest that you use one of the 2.4G video links. They might work with a sq. wave

martin

That depends on what you are going to use the clock for at the receive end. If it needs to be in sync with some data stream, you need to consider where that data came from and what sort of timing errors are tolerable.

--
Paul Hovnanian     mailto:Paul@Hovnanian.com
------------------------------------------------------------------
When I was in high school, I remember boys and girls slept
together all the time. We called it algebra class. -- Jay Leno

What are you doing that requires the clock signal?

Luhan

--
Why would you want to do that?

In message , dated Thu, 31 Aug 2006, koko writes

Don't top-post, PLEASE!

It's not at all difficult to get an exact square wave from a sine wave. To send square waves by radio, you need a bandwidth of at least 5 times the fundamental frequency (ten times if you use DSB AM) and more likely nine/eighteen times, because if clock symmetry matters, so will slow edges.

--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
2006 is YMMVI- Your mileage may vary immensely.

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

I think that article should not have been sent. It is just about 100% wrong.

--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
2006 is YMMVI- Your mileage may vary immensely.

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

--- Don't be sorry for Google groups, just bottom-post.

You misunderstood my question. I was trying to find out why you think it's necessary to send a square wave. Had you answered with a reason outlining the technical details, someone here might have been able to help you with an alternate solution, because the sad fact is, you _can't_ send square waves. If you try to you'll wind up sending the fundamental frequency as a sine wave and all of the odd harmonics of the fundamental, as sine waves, at the same time.

So, if you send a 1MHz square wave you'll wind up sending 1MHz,

3MHz, 5MHz, 7MHz, 9MHz, and so on, as well, which is surely going to make _someone_ unhappy.

-- John Fields Professional Circuit Designer

so john, what is your opinion about FSK (frequency shift keying), or BPSK (binary phase shift keying), does it work?

Not necessarily, if you can manage to modulate (and demodulate, of course) the aether. ;-)

Cheers! Rich