Lunt 60 Tha tuning

[wkyee]

The tuning on my Lunt 60 THa seems to have changed. Before at each end the disk was featureless except for sunspots, with all the detail brought out when the tuning wheel was near the center of its travel. Now only one end is featureless, and the best tuning is at or near the other end with no de-tuning beyond that.

Does this sound like something is wrong?

[Allcart]

Not sure, but it sounds to me that you may have turned the wheel past its limit and started on a new thread position. I know that might seem hard to understand, but its hard to explain.
When I got my LS60f the instructions were to turn the tuning wheel but not to force it past the stop. I did accidentally go too far and the adjusting wheel seemed to start tuning again but with a pre-tilt on the etalon. I carefully turned the wheel back again to its original position and its fine now.

Of course I could see the LS60f etalon and could see what had happened, but with your etalon being inside the scope, you may not be able to see this at all.

[colinsk]

Temperature and altitude will affect the wheel position as well.

[wkyee]

Well, the problem continues. There is something wrong with the tuning, and I feel I am not getting the full range out of it. Is it time to contact Lunt?

[solarchat]

that makes perfect sense as the air pressure has changed drastically with the season. Has the temperature changed a lot since you got the good tuning in the center? Have you changed altitude by any chance?

[wkyee]

Well, it did get warmer as summer came. No change in altitude.

[solarchat]

well, thats why it has such a wide range, to compensate for changes in air pressure due to heat or altitude. It wont always be "in tune" in the same place, or there wouldnt be a need for a tuner...lol

[swisswalter]

Hi Willie

don't worry be happy. You can always show us pics from what you get and we can comment on them

[wkyee]

Pictures I am not so good at. But the problem seems to be getting worse. I cannot get a good overall tuning of the disk. Time to call Lunt methinks.

[swisswalter]

Hi Willie

they will most probably also ask for pics in order to better understand what happens at your end