[time-nuts] No 1 PPS output on a Tbolt
pvince at theiet.org
Fri Feb 12 12:24:51 UTC 2010
I put a dual-colour (red-green) LED in a BNC plug for just this
sort of purpose. No series resistor - the 50-ohm source impedance
limits the current nicely. With dual-colour, I can see both positive
and negative pulses. 100ms pulses are perfect, 10ms OK, 1ms are very
dim, but there is no chance of seeing the 10us pulses from the
As others have said, I set the (analogue Tek 2445) 'scope to
10us/div, 2 volt/div, 50 ohms, DC positive edge trigger, and waggle
the trigger level. The display is dim, but visible. A slightly
slower scan would narrow and brighten the pulse on a tired tube.
On 8 February 2010 15:15, Robert Darlington <rdarlington at gmail.com> wrote:
> Try hooking the output to an LED. It's very difficult for me to see the
> pulse on my analog scopes but there is no arguing with the blinking light.
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