100Mhz crystal
 

I am collecting the parts for Elso's async-clock and I am having a little trouble finding the 100Mhz crystal. Where can I buy one or can someone sell me one?

Thanks,
P. Sugano

you can do it with a lower freq xtal
 

if you overdrive a xtal oscillator you generate a series of harmonics -- just use a bandpass filter at 100MHz for a crystal whose frequency is an integer dividend of 100 MHz. (This is how I used to operate 50Mhz (6 meters) ham transmission with an 8.333 MHz crystal.

or you can buy an XO for the frequency in question.

http://www.mfelectronics.com/products/xo/

I have bought some off this place :

www.klove.nl

Not cheap though.

Regards,
Joe Ling
Malaysia

They're probably made in your country and travelled to Holland and back again ;)

Re: 100Mhz crystal
 

The 100Mhz frequency is somewhat arbitrary, Kusonoki used a 50 MHz crystal, and Elso himself once said that any frequency > 45 Mhz could be suitable.

In my ASR I use a 80 MHz canned oscillator from a old server motherboard, but maybe I'll try different frequencies as I have several of them available.

Cheers

Andrea

Re: you can do it with a lower freq xtal
 

or you can buy an XO for the frequency in question.

http://www.mfelectronics.com/products/xo/ [/B][/QUOTE]
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Doing a serch for lowjitter XOs, one soon finds that the low jitter ones all hacve ECL or PECL outputs which appears lower than TTL.

What precisely are the differences?


:confused:

ECL does not saturate, so it is devoid of problems like ground bounce that saturated stuff has. It is always on, and so the output swing will always be a small fraction of the rail voltage.

Jocko

[QUOTE]Originally posted by Jocko Homo
[B]ECL does not saturate, so it is devoid of problems like ground bounce that saturated stuff has. It is always on, and so the output swing will always be a small fraction of the rail voltage.

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Thanks Jocko; what then is comlementary PECL? And can these ECL and PECL chips be used directly in place of TTL for clockling transports and adc chips?

Pl explain also WE ARE DEVO:whazzat:

You never heard of DEVO ?!?!!? With Google it took me 1 sec.

http://www.freedomofchoice.com/devo/about.asp

Re ECL
 

As good a place to start as any.

www.onsemi.com