I want to use my AMSAT Transverter with external 10MHz GPSDO...
In the current setup a 40MHz OCXO is used and a GPS module V1.
I understand, that the GPS module is for additional strings output on the OLED display only.
From schematic I understand, that the 40MHz from OCXO is used to for 10MHz Reference output port and as reference signal for the Upconverter (configurable).
How can I change the setup to be controlled from an external 10MHz GPSDO signal??
Somewhere it´s decribed, that Pin5 of J2 (GPS module connector) shall be used. This is 1PPS signal.
But I do not understand why I should short pin3+4 of J2, resulting in hanging startup screen of OLED.
Which device (IC) is responsible for disciplining the 40MHz to GPSDO signal??
How can the selection be configured correctly??
Maybe a ext. 40MHz GPSDO an option (like Leobodnar device)??
Actually, sine wave signals used, what´s needed to convert the levels (3,3V to 1V)??
Thank you for your help in advance.