Portsdown and Langstone external GPSDO

[HB9IAM]

I want to use a GPDSO reference for Portsdown and Langstone.
With a Puto rev. C and firmware V0.32 or 0.35, the synchronization is perfect.
But to transmit an image, you need the "Dirty" firmware.
After installation, the external reference doesn't work;
the Langstone still use the Pluto's TCXO.
The Putty command "fw_printenv refclk_source" indicates "refclk_source=external,"
but the reference comes from the Pluto's internal TCXO !

What's wrong ?
Pierre HB9IAM

[g0mjw]

What are you doing wrong?

Perhaps you need to specify the clock?

https://wiki.amsat-dl.org/doku.php?id=e ... export_pdf

fw_setenv refclk_source external
fw_setenv ad936x_ext_refclk_override "<40000000>"
pluto_reboot reset

Or perhaps you are using firmware for a Rev B. As you don't specify which "dirty" firmware version nor where you got it, there is no way to tell.

Mike

[g4eml]

External reference clock support was added to the official pluto firmware at V0.32 to support the Rev C hardware.
Any modified firmware based on an earlier official version will not use the external clock settings. The environment variables can still be set but they won't do anything.

Langstone is not sensitive to firmware version and should work OK with any official or modified versions.

Portsdown needs to use the modified firmware that supports DATV.

Colin G4EML