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<DIV>In a message dated 2/27/2008 3:17:42 A.M. Westeuropäische Normalzeit,
chris@chris-bartram.co.uk writes:</DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2><BR>If
it's designed well, a low-noise VCO based on a quarter-wave ceramic coaxial
<BR>resonator could be locked to the 125MHz oscillator using a sampling phase
<BR>detector (or a suitable harmonic mixer...). I'm still working on that. A
<BR>phase/frequency detector isn't suitable and a divider chain would have its
<BR>own noise contribution. If the loop bandwidth is kept reasonably large and
<BR>the oscillator stays within the lock-in range of the loop, that could make
a <BR>relatively simple and compact 1GHz reference.<BR><BR>Vy
73<BR><BR>Chris<BR>GW4DGU<BR></FONT></BLOCKQUOTE></DIV>
<DIV></DIV>
<DIV>That is correct, a harmonic sampler/mixer and a VHF crystal like 125 MHz
based, and a modern multi resonator based VCO will do the trick. I never need
exactly 1GHz but some offset to avoid spurious signals.</DIV>
<DIV> </DIV>
<DIV>73 de Ulrich, N1UL</DIV></FONT><BR><BR><BR><DIV><FONT style="color: black; font: normal 10pt ARIAL, SAN-SERIF;"><HR style="MARGIN-TOP: 10px">Delicious ideas to please the pickiest eaters. <A title="http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/2050827?NCID=aolcmp00300000002598" href="http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/2050827?NCID=aolcmp00300000002598" target="_blank">Watch the video on AOL Living.</A></FONT></DIV></BODY></HTML>