Some of the first NexStar+ hand controls were delivered with a flaw in the international city database.
The NexStar+ hand controls look different than the previous NexStar hand controls. The most obvious differences are ridges on the arrow keys and the Celestron logo key at lower left of the keyboard layout.
The bug symptoms show when doing an alignment using the city database and only when choosing a city outside the United States. When such a location is selected, the hand control gets the wrong latitude and longitude information. Since the proper location is critical for the scope’s alignment procedure, you can’t align your scope. (NOTE: this does not affect the GPS-equipped CPC and CPC Deluxe models, which get their time and site information from the GPS satellite system and not from the hand control database.)
For locations outside the US, you can work around this problem by using the Custom Site option to manually enter your latitude and longitude when first setting up the alignment. (You can get these coordinates for your city or observing site from your scope’s manual, a map or atlas, a GPS or Google Earth.)
If you have already attempted an alignment, the hand control remembers the city you input and must be reset. Use MENU > UTLITIES > FACTORY SETTINGS. Press the zero key and cycle the mount power. You can then either begin the alignment process as above and enter the custom site or set it under MENU > SCOPE SETUP > SETUP TIME-SITE > CUSTOM SITE and manually enter your latitude and longitude.
Celestron now has a firmware fix for this problem as well. It does require a download of a special version of the new Celestron Firmware Manager (CFM).
CFM is a Java application and requires Java 6.x to be installed on your computer. To verify the installation of Java on your system, visit
and click on the big red button. That will take you to a web page that will display your current version and then give you the option to update. You only need version 6.0 or higher to run CFM.
After verifying and (if needed) updating Java, download the special version of CFM here:
Unzip this file to its own directory. There will be a folder inside with the name CFM_0.7.1333.top. Go inside of it and find the file CFM.jar.
Now your computer must be connected to the hand control using the #93920 NexStar RS232 cable. (You may also need the #18775 USB-RS232 cable if your computer does not have a RS232 serial port.) Turn on the mount.
Next, click on the file CFM.jar to run CFM.
When the special CFM version is run, it detects and connects to the hand control and goes online to download the firmware to fix the bug. A typical update will be finished in 10 seconds or so.