> Azelio wrote:
>>Usually the external reference input of measuring equipment is >>internally squared, so if you feed a square or sine wave there should >>be no difference. > Some external reference inputs may be DC coupled and zero-switching, > in which case unipolar logic levels will not work well. I don't know > of any specific equipment to which this may apply, but if you try it > and it doesn't work well it is one thing to consider. An external > coupling cap (or AC coupling the output internal to divider) should fix it. > Also, 74AC logic level (~ 5 Vpp) may be a little hot for some > reference inputs. Many reference inputs present a load impedance > higher than 50 ohms to the source (often ~ 1k ohm), so you may not > get the divide-by-2 attenuation from the open-circuit voltage that > you expect in a matched system. In this case, an external 50 ohm > termination will reduce the level to ~ 2.5 Vpp. > Best regards, > Charles > _______________________________________________ > 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. 09/05/2013 19:42 Charles, Azelio. Many thanks, just what I needed, I am glad I asked, info noted, all the best gentlemen! -- Best Regards, Chris Wilson. _______________________________________________ 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.
