Well, I took a look at a non-repetitive/single-shot waveform today and indeed in a room with the lights turned down a 465B scope *will* display a waveform up to and including the top sweep setting of 20 ns per division. The waveform is weak but present at 20 ns/div. The wave form will not be seen if the room lights are on, however - even 'shielding' the CRT with one hand won't do it - the room must be dark. Given three of four 'shots' I can deduce the amplitude and pulse-width of said single-shot event. A pulse train of three or four pulses at 40 KHz was rather straight forward at 10 us per division. Reading the data bits would take a little practice and I have used such 'cheats' in the past as a small piece of paper demarking where the 'bits' that are to be should appear on the CRT ... Even in the bygone days of 'analog storage scopes' (preceeding digital storage scopes) this was often the technique used because of the limitations of the 'writing speed' of most storage scopes. The biggest use I ever for 'storage' scopes was in spectrum analyzers when set for the narrowest IF bandwidths requiring a a sweep rate of one or two seconds/div im order to observe 60 or 120 Hz 'sidebands' due to power supply ripple on a transmitted TF carrier ... Jim ----- Original Message ----- From: "Donovan Parks" To: Sent: Thursday, April 18, 2002 8:21 PM Subject: [EE]: viewing non-periodic waveforms with an analog scope Hello, I have a Tektronix 465 analog scope and it works wonderfully for viewing periodic signals. I've now come to the point where I need to view a 40kHz square wave that lasts for only three periods (and thus is non-periodic). I can set the scope to single sweep mode and get it to trigget on the first rising edge, but the signal disappears far to fast for me to analysis it. Turning the time base down doesn't help as the width of the signal shrinks in proportion. Is there any way to use an analog scope to view this waveform? Would a digital scope solve my problem (I could at least try and capture the screen with a digital scope)? What do others do when trying to observe non-periodic waveforms? Thanks, Donovan -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body