I just remember the 19 kHz was way off until I replaced the cap that supposedly drifts beside the trimmer. I could get 19 kHz only near the end of the trim pots travel.
Here's the schematics from the PL5000S2 Owners Manual that was unavailable for download and I had to buy and have mailed. Yes, the Owners Manual. Never did find a S2 black dial Service Manual. Not sure they ever had one.
One of the schematics was very faint, not a good scan, but here it is.
