A time interval counter or equivalent with less acoustical noise and
internal jitter than the Wavecrest would be nice.
Bruce
Said Jackson wrote:
Guys,
The dts needs to be driven by square waves, driving them with sine waves gives
jitter values that are displayed significantly too high due to trigger noise.
Holzworth makes a small sine wave to square wave converter that can drive 50
ohms. Use a DC block and an attenuator on the cmos output to avoid damaging the
dts inputs. You can make your own converter using a single fast cmos gate,
resistor, and blocking cap. By using hand-selected gates I was able to achieve
less jitter with that circuit than what the Holzworth box was able to achieve.
Doing that conversion can bring down the measured rms jitter on a very good
10MHz sine wave source from 10ps+ to less than 2ps - basically at or below the
noise floor of the dts.. Once you run at the units' noise floor, you know your
source is quite good..
Bye,
Said
Sent From iPhone
On Aug 20, 2013, at 18:51, Ed Palmer<[email protected]> wrote:
Adrian,
I used Timelab to assess the reaction of the DTS-2077 to different sine wave
inputs. The differences in the noise floor are surprising. The attached
picture was made by taking the output of an HP 8647A Synthesized Generator
through a splitter, and then through different lengths of cables to the inputs
of the DTS-2077. The combination of splitter and cable loss meant I couldn't
get +7 dbm @ 1 GHz. If I could have, the 1 GHz line might have been lower than
it was.
Ed
On 8/20/2013 4:42 PM, Adrian wrote:
Ed,
thanks for posting!
I'm still looking for a MUX board for my faulty 2077.
Is there anyone using a DTS-207x with TimeLab?
Adrian
Ed Palmer schrieb:
FYI, I did a teardown on my Wavecrest DTS-2077. It's posted here:
http://www.eevblog.com/forum/testgear/wavecrest-dts-2077-teardown
Ed
<DTS-2077 Noise Floor.png>
_______________________________________________
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.
_______________________________________________
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.
_______________________________________________
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.
