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Mini-circuits ZFSC-8-1 a a reference distribution

MS
Mark Sims
Thu, Apr 13, 2017 2:39 AM

My UCT-2008 rubidium reference uses the same splitter.  It is driven by a LPRO rubidium through an amplifier circuit which also drives a divider chain for producing several TTL level frequencies.  One issue to be aware of with splitters can be poor reverse isolation of the outputs.  I have not seen any issues with mine, but I don't use it for anything where that is likely to be a problem.


I recently purchased the subject device, Mini-circuits ZFSC-8-1

My UCT-2008 rubidium reference uses the same splitter. It is driven by a LPRO rubidium through an amplifier circuit which also drives a divider chain for producing several TTL level frequencies. One issue to be aware of with splitters can be poor reverse isolation of the outputs. I have not seen any issues with mine, but I don't use it for anything where that is likely to be a problem. -------------------- > I recently purchased the subject device, Mini-circuits ZFSC-8-1
JH
Jerry Hancock
Thu, Apr 13, 2017 5:29 AM

I have circulators but not on the splitter.  Since there are no mixers down stream, would reverse isolation be necessary in this application?

On Apr 12, 2017, at 7:39 PM, Mark Sims holrum@hotmail.com wrote:

My UCT-2008 rubidium reference uses the same splitter.  It is driven by a LPRO rubidium through an amplifier circuit which also drives a divider chain for producing several TTL level frequencies.  One issue to be aware of with splitters can be poor reverse isolation of the outputs.  I have not seen any issues with mine, but I don't use it for anything where that is likely to be a problem.


I recently purchased the subject device, Mini-circuits ZFSC-8-1


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I have circulators but not on the splitter. Since there are no mixers down stream, would reverse isolation be necessary in this application? > On Apr 12, 2017, at 7:39 PM, Mark Sims <holrum@hotmail.com> wrote: > > My UCT-2008 rubidium reference uses the same splitter. It is driven by a LPRO rubidium through an amplifier circuit which also drives a divider chain for producing several TTL level frequencies. One issue to be aware of with splitters can be poor reverse isolation of the outputs. I have not seen any issues with mine, but I don't use it for anything where that is likely to be a problem. > > -------------------- >> I recently purchased the subject device, Mini-circuits ZFSC-8-1 > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
BK
Bob kb8tq
Thu, Apr 13, 2017 1:23 PM

Hi

If the circulators are good to 10 MHz and you have eight of them to play with, then certainly they can
be turned into isolators. Unless you have a really unique source of them, that kind of gets this out of
the cheap seats.

The “why” of isolation is very application dependent. Without knowing what you are trying to do, there is
no way to tell if it’s an issue or not. To some degree it’s one of those “if I can do it cheap why not” sort of
things. You do run into back feed issues in all sorts of setups. They can be a major pain to track down.
My main reason for mentioning it is because normal mixer isolation numbers assume pretty darn good
terminations. There are unterminated combos that also give good isolation. There are some that give
really rotten isolation. That’s right back to being a pain to track down ….

Bob

On Apr 13, 2017, at 1:29 AM, Jerry Hancock jerry@hanler.com wrote:

I have circulators but not on the splitter.  Since there are no mixers down stream, would reverse isolation be necessary in this application?

On Apr 12, 2017, at 7:39 PM, Mark Sims holrum@hotmail.com wrote:

My UCT-2008 rubidium reference uses the same splitter.  It is driven by a LPRO rubidium through an amplifier circuit which also drives a divider chain for producing several TTL level frequencies.  One issue to be aware of with splitters can be poor reverse isolation of the outputs.  I have not seen any issues with mine, but I don't use it for anything where that is likely to be a problem.


I recently purchased the subject device, Mini-circuits ZFSC-8-1


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Hi If the circulators are good to 10 MHz and you have eight of them to play with, then certainly they can be turned into isolators. Unless you have a really unique source of them, that kind of gets this out of the cheap seats. The “why” of isolation is very application dependent. Without knowing what you are trying to do, there is no way to tell if it’s an issue or not. To some degree it’s one of those “if I can do it cheap why not” sort of things. You do run into back feed issues in all sorts of setups. They can be a major pain to track down. My main reason for mentioning it is because normal mixer isolation numbers assume pretty darn good terminations. There are unterminated combos that also give good isolation. There are some that give really rotten isolation. That’s right back to being a pain to track down …. Bob > On Apr 13, 2017, at 1:29 AM, Jerry Hancock <jerry@hanler.com> wrote: > > I have circulators but not on the splitter. Since there are no mixers down stream, would reverse isolation be necessary in this application? > > >> On Apr 12, 2017, at 7:39 PM, Mark Sims <holrum@hotmail.com> wrote: >> >> My UCT-2008 rubidium reference uses the same splitter. It is driven by a LPRO rubidium through an amplifier circuit which also drives a divider chain for producing several TTL level frequencies. One issue to be aware of with splitters can be poor reverse isolation of the outputs. I have not seen any issues with mine, but I don't use it for anything where that is likely to be a problem. >> >> -------------------- >>> I recently purchased the subject device, Mini-circuits ZFSC-8-1 >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.