In article , Bill Baka
wrote:

lw1ecp wrote:
I saw one with a modified Wien-bridge that had an AGC (...)
Thanks Bill for your immediate answer!. Yes, RC oscillators have
impressive f spans: you change R or C by 10:1 and f changes 10:1, not
its square root. But... my needs go into the many hundreds MHz, sorry,
I have to stick to LC oscillators.


Many hundreds of MHz? Are you trying for D.C. to daylight? I could poke
around a bit and see if I could trip over something while I look for
parts for my own projects. Are you looking to build or buy? It seems you
want a circuit to build. Am I on the right track? Some of the older ARRL
handbooks may have a circuit or two. Lately I have seen them migrating
towards VHF and UHF and higher frequency stuff.
Good luck.
Bill Baka


A typical way of getting this kind of range is to use a pair of
oscillators, at least one voltage controlled, a mixer, and a low pass
filter -- with the amplitude stabilizing loop described previously.

Use a pair of YIG tuned oscillators and a wideband mixer, and you can
get as wide a range as you want -- a lot of sweep generators work this
way.

You could use a pair of Mini Circuits VCOs in the 2 to 4 GHz range and
build a vco with a few hundred MHz range.