Just before I purchased mine I found a scope on Craigslist for 200.00. I think it was a Tektronix - about 20 or 50 Mhz - 4 inch screen - no color. He wouldn't budge on the price. I almost bought it but I shopped around and found this one for just a few dollars more - brand new. Better deal!
I heard that Hantek found that the mod was so easy and everyone was doing it that they just sell the 200 Mhz in a 70 Mhz case. Seems they had to modify the 200 down to 70 so they just quit modifying them. I think mine is a 200 Mhz but I don't know. 70 Mhz or 200 Mhz - it works fine for me.
I wasn't interested in connecting my scope to USB either. If I didn't have this problem I doubt if I would try it but I wonder if it would allow me to adjust the controls. Might give some insight on where the problem lies. I'm going to give it a try when I have time.
I've seen several videos and photos of the inside of this scope but haven't seen anything with the front removed. I hate to dig into it if the supplier or Hantek can repair it. With my luck I'll just make things worse.