tag:blogger.com,1999:blog-7396057548824140336.post354727965027139968..comments2023-07-31T22:42:16.719-07:00Comments on WA0UWH - Electronics & HAM Radio Blog: A New Master ClockEldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-7396057548824140336.post-17928754051086763552012-03-05T12:02:01.779-08:002012-03-05T12:02:01.779-08:00Christoph,
Thanks for the ideas and pointers, I n...Christoph,<br /><br />Thanks for the ideas and pointers, I now have several TCXO's on order. One at 40MHz and another at 52MHz each with a stability spec of +/-0.5ppm. <br /><br />See: http://goo.gl/8f4Mv<br /><br />I think each will work with a configuration of: <br /><br />_CLKMODE = XTAL3 + PLL2X<br /><br />I like to stay with the standard 80MHz clock speed, but it is fun to Over-clock as well.<br /><br />Eldon - WA0UWHEldon R. Brown SRhttps://www.blogger.com/profile/16271671761017534867noreply@blogger.comtag:blogger.com,1999:blog-7396057548824140336.post-36077172670002963782012-03-05T03:36:33.624-08:002012-03-05T03:36:33.624-08:00Hello Eldon,
have you thought about using a TCXO a...Hello Eldon,<br />have you thought about using a TCXO as your master clock?<br /><br />They are available in SMD package sizes similar to the chip you selected and you would have about the same or better absolute frequency accuracy as your RTC.<br />The downside is that I haven't seen one with a frequency above 52MHz or below 8MHz.<br /><br />If you're interested, take a look at http://forums.parallax.com/showthread.php?137941<br /><br />Also, I think that for your current configuration you should probably have<br /><i>_CLKMODE = XINPUT</i><br />instead of<br /><i>_CLKMODE = XINPUT + PLL1X</i><br /><br /><br />ChristophChristoph_Hhttps://www.blogger.com/profile/11248214763329220616noreply@blogger.com