EMRFD Message Archive 1702

Message Date From Subject
1702 2008-06-12 07:02:09 Markus Hansen Re: Digest Number 545
Hi Rick. I am surprised how much "lore" there is bouncing around on the WEB
about analogue VFO"s and how bad they are. Most of what I have read is just
a bunch of bunk. Doug, W1FB (now a SK) and Wes, W7ZOI used high quality
test equipment to quantify VFO drift and then came up with some very good
recommendations as to how to select components build a stable a VFO. Then
Wes, showed us how to measure drift with very simple test equipment and a
warming oven, then how to employee different temp. compensations to control
drift. And following these principals you can make, as you agree, a very
stable VFO, with the added benefit that they typically have very low phase

These days, I am measuring and making more notes than I ever did before as I
build different kinds of ham equipment. Being I am not an electrical
engineer, I learn from others who have already gone down the road I am
heading. What I have learned is, 1. build in modules, 2. use tested
circuits that have been built by someone you can trust, 3, first, build the
circuit exactly as the author built it, 4. then test and measure it. 4. make
really good notes, and 5, last but not least if you think you can improve
the circuit, go ahead but at least you know where you are coming from.
Works for me.

This EMRFD Yahoo group is fantastic. I really appreciate all the input from
the different individuals who are willing to take a few moments and share
their experiments, their success and failures too. We learn so much from
each other.

Enough rambling. Happy homebrewing fellows,

Markus VE7CA
web: www.shelbrook.com/~ve7ca