TCXO / VC-TCXO for pic usage

[longpole001]

the requirement is for temp controlled XTl osc clock input to the pic , so the inernal is not used so that drift wont be an issue ( as much)

the problem lies in that i need to adjust this clock as it ages, this is done by using a OSCtune when having the internal clock , how ever when using a ext osc or xtl osc any adjustment must be external to the PIC

Some / not all TCXO have fine adjustment trim pot built in , but many do not

I looked at external time base chip , but often these are more costly an option for what i have found so far

I believe the best way , at lest at the moment is to use an RTC with the TCXO built in and use the SQW output as a referance ( ds3231 ) with sync from the internal clock to monitor / adjust the OSCtune register ,

[Heckler]

Check this out...
http://www.romanblack.com/xoven.htm

and there are a LOT of other articles regarding accurate timing on his web site, here...
http://www.romanblack.com/index.htm#elec