Thanks everyone, i think the key here is to repeat with faster chips. I appreciate the everyone's comments.
On Thu, Mar 24, 2011 at 4:26 PM, Bob Camp <li...@rtty.us> wrote: > Hi > > The TBolt is designed to drive 50 ohms on the 10 MHz output. Level is above > 7 dbm on the ones I have looked at. > > Bob > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Greg Broburg > Sent: Thursday, March 24, 2011 5:20 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Squaring Tbolt 10Mhz output > > what is the output drive circuit and what is the drive > level / source impedance from the Thunderbolt? > > Greg > > > > > On 3/24/2011 2:10 PM, Hal Murray wrote: > >> I'm not sure everything can handle the 10Mhz signal. > > Bingo. > > > > LM339 (National data sheet) > > Response time: 0.5 us > > > > CD4049B/CD405B (from TI data sheet) > > Rise time is 80 ns > > Fall time is 30 ns > > Those are typicals at 5 V with a 5V input signal. > > > > > > The LM399 says "low power" which usually means low speed. > > > > I occasionally go "oops" when I sanity check the speed on a circuit I'm > about > > to build using HC/LS parts. They aren't very fast, and the old 4000 > logic > is > > even slower. > > > > 10 MHz is about the corner for HC. I use the HC163 (4 bit binary > counter) > as > > an example. It has a max clock frequency of 25 MHz, so you think "no > > problems" at 10 MHz. But the setup times are 30-40 ns and the clock-out > are > > 40-50 ns so doing anything interesting at 10 MHz gets tight. > > > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Best Regards, James Fournier I.T. Services 6a Ave. de Lourdes Pointe-Claire, QC H9S-4R2 514-562-0645 ja...@jfits.ca www.jfits.ca _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.