Charles
would you mind sharing 1 second frequency data that you get out of the
tbolt to get an idea what is possible. Looks like we are not the only ones
trying to improve frequency performance and hopefully some one will share
settings.
Bert Kehren

In a message dated 9/10/2016 6:42:17 A.M. Eastern Daylight Time,
csteinmetz@yandex.com writes:

Bert  wrote:

looking

greatly.

Well, I spent the holiday  weekend looking for the "safe place" where I
recorded my final Tbolt  tuning parameters -- without success.  After I
tuned them and  qualified them as fit for long-term duty, I disconnected
the com ports and  stashed them away in a very quiet and hard to access
location with just  the 10MHz coax connected, so I can't use the comms to
extract the  parameters without disturbing the Tbolts (which have now
settled nicely,  undisturbed for ~10 years).

But what I did wasn't rocket science -- I  just read up on the tuning
parameters, determined which ones would likely  affect the stability of
the 10MHz output, made some educated guesses about  the likely best
settings, and started playing.  It took me several  weeks of
experimentation (on and off), and the parameters I settled on  were
somewhat different between the two units I kept (primarily, the loop
time constant and damping, which ideally should be set to complement the
particular OCXO in each unit).

I recommend extreme caution when you  hear suggestions to use low loop
damping, or to monkey very much with the  oscillator scale factor.  I
found that high damping (far above the  1.2 default value) worked best
for my units.  (Like you, I care most  about the stability and accuracy
of the 10MHz output.  I don't even  have the PPS turned on.)

Before you do anything else, I strongly  suggest a full factory reset to
put everything into a known state, and  work from there.

You have received some advice to use the "autotune"  routine in Lady
Heather.  I seem to recall several people reporting  that it worked well
for them, and there is nothing to lose by trying  it.  However, in my
case it screwed up the tuning of both units so  badly that I had to do
factory resets and then re-enter my custom  parameters.  I might have
been using a version of LH that didn't have  the latest autotune code, or
perhaps the autotune function needs to start  from factory default
settings, or maybe the phase of the moon was wrong --  but I was sure
glad I had recorded the tuning parameters I worked out by  experiment, so
I didn't have to start over again!  Just be prepared  to do another
factory reset and start experimenting if autotune doesn't  work to your
liking.

So, I would suggest: (1) do a full factory  reset, let it run for a few
weeks, and take data; (2) use the autotune  routine, let it run for a few
weeks, and take data.  If you are not  satisfied with the results at this
point, (3) do another full factory  reset and begin experimenting manually.

Best  regards,

Charles

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Bert wrote:

You are coming very late to the Tbolt party.  There was a veritable
blizzard of posts about optimizing Tbolt performance, which began maybe
10 or 11 years ago (??) and lasted for several years, and a steady
trickle since then.  Everything that is possible to be said was posted,
often several times.  Go back in the list archives and read this
material -- it will answer all of your questions (and lots more that you
haven't asked yet).

Best regards,

Charles