Said, Your drawing looks better than those by Bob Pease, and he was never embarrassed by his :) Thank you for your extensive contributions to time nuts
Didier KO4BB On Tue, Nov 25, 2014 at 7:28 PM, S. Jackson via time-nuts < [email protected]> wrote: > Guys, > > I never expected such an intense discussion about using and buffering the > outputs from the LTE-Lite board since the actual circuit to use can be > quite simple. > > To address these questions, I drew up a simple schematic that uses a DIP-14 > 74AC04 gate, six resistors, and two caps. Everyone who can solder should > be able to build this simple circuit as a dead-bug type build on a > copper-clad board. > > This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed > RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms > terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on > pin 14 of that part on the eval board, even though I would strongly > suggest to use a separate low noise 3.3V or 5V power supply to power the > 74AC04 > chip. > > You can add 100nF caps in series to the two RF signals before they feed > into the coax output connectors for less power consumption and removing DC > for > instruments that don't like DC inputs. > > Using a single IC for the three signals will result in crosstalk between > the signals, but it should be clear from the schematics how one could break > up the signals by using three independent ICs to minimize crosstalk. > > We use this circuit in a small box here using SMT components, and it works > really well. > > Excuse my horrible writing, using keyboards has made my fingers numb.. > > Hope that helps, > Said > > _______________________________________________ > 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. > _______________________________________________ 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.
