On Thu, 05 Jan 2012 18:54:31 +0100, EB4APL <[email protected]> wrote:
>On 05/01/2012 16:49, David wrote: >> On Thu, 05 Jan 2012 01:44:13 -0800, Hal Murray >> <[email protected]> wrote: >> >>> [email protected] said: >>>> Have an older Tek 465 scope that is in only "fair" shape and I see nothing >>>> on that pin but milivolt level sine wave of about 60MHz. I can't set the >>>> scope to show any hint of a PPS ... >>> I do have a 465. You should be able to see a 1 uSec PPS. >> 60MHz is about a 6nS rise time and is easily fast enough to see it. >> >>> Now turn up the Intensity until you can see the pulse. It might help to >>> turn >>> down the room lights. >> This is the problem. With a 1 second repetition rate, the brightness >> is going to be very low. >> >> The old ways of viewing such a low repetition rate signal include >> using a hood or dark room, special CRT phosphors, photographic film, >> MCP (micro channel plate) intensified CRTs, and of course analog >> storage and later digital storage. >> >I agree, I've seen it in a Tek 7623A with the storage on, it is quite >difficult without it. I can not imagine using my worn 7603 to see it. I rebuilt a 7834 analog storage oscilloscope for just that sort of application although I have a 2230 analog/DSO that I repaired which would be easier to use for this. I just checked and in analog mode, my 2230 can display a 1uS/div sweep at a 1 second interval without trace thickening in room light but it is dim enough that I sure would not want to use it for other than verfying the pulse is there. _______________________________________________ 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.
