My old '465 will trigger on the 1pps, but it's far easier to see the trigger LED flash than finesse the brightness/sweep to make it visible - something possible only on a 'scope with a decently bright tube. Another cheap/easy trick to detect the 1pps pulse is simply to "listen" to it with an audio amplifier. While it can be heard on my Tbolt and '3801 with just a headphone connected, a cheap audio amplifier works better, stretching the pulse out and making an obvious "tick" at the 1 PPS rate. I suppose that a diode/cap (1N914/1000pf) could be used to further stretch it... Clint

Set the scope sweep speed to 10 milliseconds per division and then even a dull scope is easy to see. You are looking for trigger events from the 1PPS, not the 1PPS itself. John WA4WDL -------------------------------------------------- From: "C. Turner" <turner@ussc.com> Sent: Monday, July 23, 2012 2:26 PM To: <time-nuts@febo.com> Subject: Re: [time-nuts] Trimble T Lassen 2 -suitableantenna....advice.....questions > My old '465 will trigger on the 1pps, but it's far easier to see the > trigger LED flash than finesse the brightness/sweep to make it visible - > something possible only on a 'scope with a decently bright tube. > > Another cheap/easy trick to detect the 1pps pulse is simply to "listen" to > it with an audio amplifier. > > While it can be heard on my Tbolt and '3801 with just a headphone > connected, a cheap audio amplifier works better, stretching the pulse out > and making an obvious "tick" at the 1 PPS rate. I suppose that a > diode/cap (1N914/1000pf) could be used to further stretch it... > > Clint > > > _______________________________________________ > 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. >