Hello Dieter,

I had once or twice seen BTS stations which had working PLL value very different from calibrated value. In order to get them close I had to use E1 hardware with high precision oscillator, then switch the hardware to the PLL-locked mode. This operation took me plenty of time.

Please tell, is it possible to set the working PLL value directly?

Best Regards, Sergey.

On Dec 2, 2010, at 6:29 PM, Dieter Spaar wrote:

Hello Sylvain,

On Thu, 2 Dec 2010 15:20:07 +0100, "Sylvain Munaut" 246tnt@gmail.com wrote:

...

The clock of the non working one might just be too off ...

See http://openbsc.osmocom.org/trac/wiki/isdnsync for a tool to calibrate (with appropriate HW).

If you don't have the equipement ... huh, good luck. You can always try random values until it works. If you have a USRP you can try to lock onto it and compare offset ...

Its possible to set the clock calibration to a fixed value, this was a feature introduced a while ago. The original clock calibration setting workes pretty good, at least from my experience. So if the clock is off due to using the E1 clock as a reference, it should be enough to set the orginal clock calibration value and switch the PLL to standalone mode.

Best regards, Dieter -- Dieter Spaar, Germany spaar@mirider.augusta.de