I purchased a DRO off ebay and the manual was pretty much worthless. The translation from Chinese to English was hilarious. This seems to be a common problem . As well the manual seemed to be for an older software version than what I had. Sent a few emails to the seller and he was very good at replying to me and sent a new manual that is actually pretty good. I had watched several youtube videos on DRO operation and those were very little help. The best I could do is pick up one or two tips from each video. Anyhow, the DRO is a JCS900-3AE and if there is any interest from other members I could share what I received. The manual is a pdf file I got by email. I am not sure how to share it but if someone needs a copy we could work it out. I have not read the entire manual yet but it is the best I have come across.