Trouble getting a good PEC with PEMPro on my 1100GTO


Bradley Rode
 

Ray (and others), I'm hoping you can help diagnose a problem I'm having getting a good PEC on my 1100GTO.
The guiding has been erratic recently, so I decided to redo the PEC.

I've included the following log files and associated PPC files:
1. PEMPro-2021-07-22-223127 is the original capture of 6 cycles with PEC off;
2. using only the worm fundamental and ignoring all others, I generated a PPC and loaded it into the mount;
3. PEMPro-2021-07-23-000156 is the verification run of 5 cycles with PEC on;
4. I then tried a refinement (fundamentals 1 and 2) by adding the xxx127 and xxx156 curves and reloaded that into the mount;
5. PEMPro-2021-07-23-010201 vfy is the verification run of the refined curve.

Unless I'm totally misreading the data, I'm not getting much, if any improvement. I'm certainly not getting down into the sub-0.5" range that I've seen others talk about. I'm seeing some odd frequencies in the graphs, but not sure how hard to chase correction on those.

Any help would be greatly appreciated. I'm losing too much sleep on this :)

Brad


Ray Gralak
 

Hi Brad,

PEC works best with consistent data. Your data with PEC off shows a variation in the 1.0x fundamental's magnitude with time, so the result is not optimal. This may be caused by very poor seeing conditions (tube currents), incorrect gear meshing, or possibly some contaminants in the grease.

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Bradley Rode
Sent: Friday, July 23, 2021 3:08 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] Trouble getting a good PEC with PEMPro on my 1100GTO

Ray (and others), I'm hoping you can help diagnose a problem I'm having getting a good PEC on my 1100GTO.
The guiding has been erratic recently, so I decided to redo the PEC.

I've included the following log files and associated PPC files:
1. PEMPro-2021-07-22-223127 is the original capture of 6 cycles with PEC off;
2. using only the worm fundamental and ignoring all others, I generated a PPC and loaded it into the mount;
3. PEMPro-2021-07-23-000156 is the verification run of 5 cycles with PEC on;
4. I then tried a refinement (fundamentals 1 and 2) by adding the xxx127 and xxx156 curves and reloaded that into
the mount;
5. PEMPro-2021-07-23-010201 vfy is the verification run of the refined curve.

Unless I'm totally misreading the data, I'm not getting much, if any improvement. I'm certainly not getting down into
the sub-0.5" range that I've seen others talk about. I'm seeing some odd frequencies in the graphs, but not sure how
hard to chase correction on those.

Any help would be greatly appreciated. I'm losing too much sleep on this :)

Brad