One customer complains the ceramic tube came out! check below photo, how can we gix it? Can we remove it for common use? The ceramic tube is from SC connector, not from the OTDR. please pull out the ceramic tube from OTDR slightly, and then install back to SC connector. If it is not easy to installed back, please buy a new SC connector. You can find many suppliers of the connector in the market.

After press booting button, power lamp is alive but display dosn't appear like the video in the link. This bug is because some system files were not loaded to memory of operation system correctly during the startup process. To solve the problem, users can press and hold power button for around 20 seconds, untill the device goes into repair mode. Then, the device will fix the bug by itself. Do not do any operations before the device turns off and turns on again by itself.

First of all, please let us know S/N number at back of OTDR. Then, our engineer will send you a software to add korean language. And then, follow these steps to upgrade your OTDR,

1) connect OTDR to PC with a USB cable
2) copy upgrade software to the root of OTDR DISC
3) disconnect from PC 
4) go to system -> general settings -> upgrade
5) Around 2 mins later, the OTDR will re-boot automatically
Do not turn off OTDR when updating.

Currently, we have these languages for customer choice when they place order,

First of all, we do not suggest users to upgrade their OTDR by themselves without negotiating with us, because we change hardware occasionally according to market supply. If any problems happen, please contact us in advace and describe the problems to our engineers. They will generate particular upgrade package for your OTDR if they think it is software (or firmware) problems. After you get the upgrade package, follow these steps to upgrade your OTDR,