On Sun, 8 Jan 2012 14:23:02 -0800, Orin Eman <[email protected]> wrote:
>On Sun, Jan 8, 2012 at 1:51 PM, Clint Turner <[email protected]> wrote: > >> Hello, >> >> After posting a few days ago about one of my '5680A's having the voltage >> converter installed - but not connected - I've done a bit of >> reverse-engineering and sleuthing around and (probably) have a fairly >> complete picture of what it would take to populate that section of the >> board. That information may be found here: >> >> http://ka7oei.com/10_MHz_**Rubidium_FE-5680A.html<http://ka7oei.com/10_MHz_Rubidium_FE-5680A.html> >> >> This page is a work in progress, using my LPRO-101 page as a template and >> unashamedly stealing a good chunk of its content - most of which is >> directly applicable, anyway! >> > >Are you sure about those resistor values? They look like 5.11K and 5.62K >(standard 1% values) to me. I agree. Besides not requiring rare and expensive 4 significant digit precision resistors which just happen to match the marking of the standard 1% resistors, the nonstandard 12.95K and 11.15K on the schematic would yield 5.23 volts. 5.62K and 5.11K will yield 5.08 volts from the nominal 2.42 volt reference on the LT1376. The 5 volt resistor selection in the data sheet would have been closer but maybe they wanted the extra 7 millivolts or were compensating for the feedback bias pin current. If noise was so important I wonder why they did not use a lower noise switching regulator or the LT1375 which supports oscillator synchronization. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
