Thanks Pete not sure my wife will let another big box in the door. I was thinking of some thing like this : http://www.onsemi.com/PowerSolutions/product.do?id=MC100E137FN a ECL 8-Bit Ripple Counter. And a 1Ghz oscillator make the measurement of differences. This should get me to the 1ns level ? But looking at the sampling heads may be close to what I want, I will look for some manuals on the web. I would want to transfer the data to a PC, would I need a GPIB Interface and some software ? I'm trying to eliminate the extra stuff like the scope tube and it's power supply and end up with a small box to interface to the computer.
----- Original Message ---- From: Pete <[EMAIL PROTECTED]> To: Discussion of precise time and frequency measurement <[email protected]> Sent: Tuesday, April 15, 2008 3:13:02 PM Subject: Re: [time-nuts] 5 MHZ PIC PPS Divider? Stanley, Jitter measurements of moderately high frequency sources can be made directly with relatively cheap used instruments. Older sampling 'scopes from H-P and TEK appear on *Bay frequently. The H-P 54120 family boxes are down to US$500 to 800 with sampling heads capable of 12.4GHz measurements. These show up about once per month. If you're trying to buy one, wait for a complete system (mainframe+sampling head) which is listed as operational & you have confidence it's actually working. These things are HEAVY & having to return a junker is painful; even if you get your money back. These mainframes have jitter capture & analysis built in. The internal trigger jitter floor is about 1ps, good enough for most measurements. The internal timebase delay feature allows measuring multi- cycle jitter out to many screens width of data. Obviously, long delays will introduce added jitter floor contribution, but it's still quite good. Regards, Pete Rawson _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
