Re: 7834 Missing Trace
I think the faint line between the peaks at the top is the flyback line (the trace intensity looks much higher in the image than it is in real life): https://imgur.com/a/KKS7vMp
I've discovered neither intensity control works, when either are moved to the maximum position their respective trace goes out of focus. No other change is visible when moving the knobs.
After some messing around, it does seem like the storage settings are working correctly. The only hiccup is the bright dot you can see at the lower left of the image. When I enter the save mode the image remains, but the dot creates a splotch that slowly radiates out. My work-around currently is to enter the save mode, then move the horizontal control all the way to the left so that the dot goes off-screen.
The scope also seems to have a long warm up time to me. The previous image has the calibration signal set to 4V after running perhaps 10 minutes. My other confusion, and I may just be the ultimate idiot here, is that the calibration signal seems to output half of what it is labeled to output. I confirmed this with an RMS multimeter. So the 4V setting outputs ~1.97V or so. It's a square wave so the RMS should be the same as the peak to peak voltage. The other decades behave similarly. Anyway, After running for maybe 40 minutes the scope begins to properly display 2V on one channel, then a bit later on the other. So I'm not sure if these just have a long warm up time or if something isn't right.