This is merely a historical archive of years 2008-2021, before the migration to mailman3.
A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/baseband-devel@lists.osmocom.org/.
Christian Vogel vogelchr at vogel.cxHi, I've measured how the 26 MHz VCXO changes frequency depending on the AFC DAC output. See the attached plots and the data file. Tapping point is between C132 and C210 (RITA Xout). On my 20 MHz scope it's 300 mVpp, but I'm hitting the bandwidth limit of the scope, the frequency counter says -0.03 V ...+0.02 V after a x10 probe (500mVpp). I'll put it in the fridge later on to check the temperature coefficient. Pictures: http://lh6.ggpht.com/_zKkNaqX3vkM/S-avbZbCmJI/AAAAAAAAAwE/EfsMRB08iJ8/s1600-h/IMG_1522%5B3%5D.jpg http://lh3.ggpht.com/_zKkNaqX3vkM/S-ave-aRv_I/AAAAAAAAAwM/3f1RfuZD05E/s1600-h/IMG_1523%5B4%5D.jpg http://lh3.ggpht.com/_zKkNaqX3vkM/S-aviUpzWNI/AAAAAAAAAwU/AshSJr3qzwM/s1600-h/IMG_1524%5B3%5D.jpg http://lh3.ggpht.com/_zKkNaqX3vkM/S-avmomSpgI/AAAAAAAAAwc/NJSJoW5fqd4/s1600-h/IMG_1525%5B3%5D.jpg http://lh6.ggpht.com/_zKkNaqX3vkM/S-avqB3veGI/AAAAAAAAAwk/uPQPARv3osk/s1600-h/IMG_1526_w_label%5B3%5D.jpg Chris -------------- next part -------------- # GPSDO locked, Ch2, Frequency, Peak/Peak: 30mV/-20mV # DAC, 1st measurement, 2nd measurement 0 25.999876 25.9998634 256 25.9999336 25.9999225 512 25.9999915 25.9999818 768 26.0000501 26.0000412 1024 26.0001089 26.0001008 1280 26.0001680 26.0001605 1536 26.0002275 26.0002203 1792 26.0002871 26.0002800 2048 26.0003454 26.0003396 2304 - 26.0003988 2560 26.0004637 26.0004581 2816 26.0005218 26.0005169 3072 26.0005791 26.0005754 3328 26.0006366 - 3584 26.0006935 26.0006915 3840 26.0007496 26.0007486 4095 26.0008047 26.0008047 -------------- next part -------------- A non-text attachment was scrubbed... Name: vcxo_meas1.png Type: image/png Size: 7854 bytes Desc: not available URL: <http://lists.osmocom.org/pipermail/baseband-devel/attachments/20100509/103dcf98/attachment.png> -------------- next part -------------- A non-text attachment was scrubbed... Name: vcxo_meas2.png Type: image/png Size: 7882 bytes Desc: not available URL: <http://lists.osmocom.org/pipermail/baseband-devel/attachments/20100509/103dcf98/attachment-0001.png>