Hi Bob,
Thanks for the quick reply, makes sense.
73
Scott
W7SLS
> On Jul 26, 2018, at 1:13 PM, Bob kb8tq wrote:
>
> Hi
>
> They are a pretty rare item. A more common approach is a disciplined
> oscillator that
> will do failover on it’s inputs. That’s still a rare item, but at least a
>
Hi
90 db will not drive the ADEV nuts, but it still will be a lot worse than a
normal standard will deliver, even at
120 db down, if the offset is a bit above 1 Hz you will still see it in an ADEV
plot.
Bob
> On Jul 26, 2018, at 5:40 PM, Scott McGrath wrote:
>
> True but if you use a good
On Thu, July 26, 2018 5:05 pm, Hal Murray wrote:
> Has anybody built a microprocessor controlled PLL to handle this case?
There are failover clock generators (integrated circuits), typically
marketed for use in telecom equipment where there is a requirement to
synchronize with a reference clock
True but if you use a good switch or PIN 90 db of isolation is easily
achievable. Yes the spur is still there but it’s 90 down and will not affect
ADEV as badly.
You could drive it further down with two switches with the alternate standard
connected to 1 port and a termination to the other.
Not quite what you are looking for, but I implemented a pair of thunderbolts
with no common parts (dual antennas power etc) into a simple RF switch.
The production manager flipped the switch on Mondays, and if either system
wasn't working I had a third system in a box ready to replace.
So for
kb...@n1k.org said:
> One interesting subtlety making something like this:
> What if the two inputs arenât quite on the same frequency? Purely as an
> example, say they are 1 Hz off from each other. If you have 60 db of
> isolation in your âswitchâ you get a 1 Hz offset spur that is 60 db
Hi
One interesting subtlety making something like this:
What if the two inputs aren’t quite on the same frequency? Purely as an
example, say they are 1 Hz off from each other.
If you have 60 db of isolation in your “switch” you get a 1 Hz offset spur that
is 60 db down. Even something much
Build one yourself, Detector diode on primary RF input when output drops use
a rf relay or PIN diode switch to fail over to backup standard.All thats
needed is a crossing detector and relay / switch driver
Yes there would be a momentary hit but it would work.
Content by Scott
Typos by
Hello,
Looking for recommendation for a ‘failover’ or ‘redundant’ switch for 10 MHz
distribution.
Not really sure of the correct term.
Something that sensed RF on primary 10 MHz, and then switched to
secondary on fail of primary.
A brief search showed several very nice $$$
