Am 10.03.19 um 01:38 schrieb jimlux:
Has anyone tried a +5V to +15V DC/DC to run an OCXO, getting the 5V
from one of those rechargeable USB power bricks. I was thinking about
portable operation.
In my case, the OCXO is something like a Wenzel streamline. I would
think that the DC/DC probably has some noise, but maybe DC/DC to a
higher voltage, then a good linear regulator to clean it up (or would
the radiated noise just leak around).
How quiet is the output from those USB battery things..I've used one
to run a RTL-SDR, but that's hardly a ultimate low noise receiver.
That's impossible to predict. These boxes normally contain one Lithium
cell and a DC/DC converter to 5V.
Its output noise depends on the skill of the designer and the mood of
the bean counter. It is probably
not a high priority. Also, there my be "effects" from the interaction of
their switcher and your's.
And the efficiencies multiply.
BUT:
3 of these Li cells deliver 12V in ultimate quality:
<
https://www.flickr.com/photos/137684711@N07/39972841815/in/album-72157662535945536/
>
The squares on the paper are 5mm.
Noise density is better than 1nV / rtHz above 100 Hz. You definitely
need a fuse. Ishort is >> 30A.
This Panasonic type is OK. There are lots of others on the market that
claim twice the power capacity
but it's a blatant lie.
regards, Gerhard
(who thinks about using a dozen of these for portable EME tests on 432 :-) )
_______________________________________________
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
