As mentioned, ~700 lines vertical resolution isn't unusual for a CRT RPTV. I wouldn't expect ~1080 lines for interlaced CRT RPTVs, unlike fixed-pixel displays. Assume, if HDNet has been DVRed, that reading is not in freeze frame, which usually delivers only TV fields (half frames). Here, that roughly halves vertical resolution (but not horizontal resolution).
While cleaning my year-2000 Philips 64PH9905 optics recently, I covered two lenses at a time and tweaked lens focus and the focus potentiometer for each tube by itself (using HDNet's resolution-wedge patterns). The focus pot is one of six on a small board (red, green blue pots for both focus and screen voltages); screen adjustments should be carefully avoided. Didn't improve crispness here. The lens/pot ranges for crispness were very narrow and tweaking didn't help.
If you can't see scan lines up close, that means electron beams within each tube are overlapping. Here, only saw these lines within inches of my 64" screen during, say, the first two years of use. One additional adjustment might restore scan line visibility and aid crispness somewhat: beam alignment and astigmatism, covered
here for Philips and perhaps for your brand elsewhere at that location, and likely in your service manual. This adjustment involves the shape of the CRT electron beam spots.
If you've tweaked focus while in zoomed mode, as you mentioned elsewhere, those adjustments should be corrected completely for normal viewing mode.
Horizontal resolution measured with HDNet's pattern, as outlined
here plays a key role in overall HD image sharpness. A few members with 1080p fixed-pixel displays have reported measuring close to 1920X1080. But many using cable STBs report only about 1300 lines with either
fixed-pixel displays or CRT RPTVs. That might be a maximum with most 7"-CRT displays. (Using DirecTV for HDNet, HD Lite might need to be factored in.)
Also, as my 'here' link above mentions, some cable STBs, and perhaps the city system they're used in, make a significant horizontal resolution difference, such as my older SA8000HD and its SA8300HD replacement (see measurements given). -- John
EDIT: And as this poster
reports , it's also possible CRT lens-coupling fluids have become contaminated and cloudy with age, reducing overall resolution.