Is my Coronado PST normal?

[38degsouth]

Hi all,
Having never used or viewed through a PST other than mine, is it normal for the tuning ring to become tight to turn at the 'end' where the prominence's/filaments become visible? It is easy (loose) to turn when 'de-tuned' to view the sunspots only, but progressively becomes harder to turn as the Ha details come into view. It has always been this way, nothing has changed since I first used it. I purchased it second-hand many years ago.
Thanks & regards, Dean

[GUS.K]

Dean, there is a screw under the rubber grip of the Etalon which can be adjusted to give more tuning range.

Ivan.

[axle01]

Just make sure you mark the original hole if you go the wrong way.

Al

[Merlin66]

Sounds pretty normal.

[38degsouth]

Thanks guys. The rubber grip on the etalon had started to split and has since detached itself completely, so I can easily see and access that screw. (I plan to use some wide rubber bands or bicycle inner tube in lieu of the original grip). As far as having a tinker? -I'll have a very gentle exploratory look on the weekend. But I guess if it aint broke, don't fix it -hence my original post. Thanks again :)

[Merlin66]

Dean,
Unfortunately we haven't found a suitable source for replacement knurled rubber rings..... on a couple of repairs I've done I used a stack of suitably sized O rings - worked well.
Moving the screw to the next hole can help in some cases, but the tilt of the etalon doesn't change much.....

[sil]

Would something like silastic (a bead of silicon rubber glue) do the needed job without impeding functionality? Worried my coronado might suffer the same fate as the pst.

[Merlin66]

The tuning ring still operates OK without the knurled band - just doesn't look as sexy...
I found the O ring stack to be visually acceptable.....

[sil]

thanks, hate the look of the coronado anyway so I might find it an improvement.