Re cross talk, I'd suggest: Fairly equal levels on all the used outputs, to minimize the effects of crosstalk between them. This is especially important if you're using RG-58 or similar cable, which leaks like a sieve. Crosstalk of this sort will tend to screw up the edges of a PPS pulse, possibly in a way as to lead to unreliable/unstable triggering of some of your devices.
As high a level as your devices will safely tolerate, unless you're concerned about leakage into other systems, like kb8tq's WWV receiver. Again, I suggest avoiding RG-58 and similar single-braid-shielded cables. This has been a significant problem for me, receiving WWV at 10 MHz. I've been able to some- what mitigate this with big clamp-on ferrite chokes, but I still have some issues. Dana K8YUM On Tue, Jan 21, 2020 at 9:28 AM Taka Kamiya via time-nuts < [email protected]> wrote: > I've tried daisy chaining 4 HP5335A. By the time signal got to the 4th > box, it was too weak to reliably drive the 1 pps. I had a terminator at > the last tee with short length of RG58s between boxes. I guess some box > puts relatively heavy load on the signal? > > I'd like to know why 10V is a bad idea. (besides too close to the upper > limit) Cross talk between what/where? > > To OP:I have video amplifiers Extron MDA-3V successfully used for this. 1 > port in, 3 ports out ones by Extron are very inexpensive at 10 dollars+/-. > I never did formal testing but reading on all counters matched exactly. > They are 75 ohms but it didn't matter in my use case. You can > change/adjust internal resisters if you are concerned. > > --------------------------------------- > (Mr.) Taka Kamiya > KB4EMF / ex JF2DKG > > > On Tuesday, January 21, 2020, 7:45:22 AM EST, Bob kb8tq <[email protected]> > wrote: > > Hi > > What are you driving? > > Most “normal” gear is pretty happy with a fairly wide range of input > levels. Obviously things > like termination and long lengths of coax can get into the act. For 4 > outputs, a passive splitter > with 6 db of loss should do just fine. You have only taken the output > voltage down by 2:1 …. > > Just for reference: > > https://www.avionteq.com/Document/53131A-specification-sheet.pdf < > https://www.avionteq.com/Document/53131A-specification-sheet.pdf> > > Calls out a 200 mv to 10V RMS input level as acceptable For a variety of > reasons, 10V RMS > is a really bad idea (cross talk ….). Lower is better in this case. > > Bob > > > On Jan 21, 2020, at 4:19 AM, skipp isaham via time-nuts < > [email protected]> wrote: > > > > Hello once again to the Group, > > > > May I ask what the current relatively simple options are for > > expanding a Thunderbolt or equivalent... output for distribution > > to multiple devices? > > > > Although I expect only two or three isolated / buffered outputs > > will be required in my example. I'm worried about signal level > > if a passive system (Mini Circuits divider or equivalent type) > > is used. > > > > Would appreciate a few quick opinions on what is practical and > > seems to work well. > > > > thank you in advance > > > > regards, > > > > skipp > > > > skipp025 at yahoo dot com > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
