This file has been used on this computer to successfully update two different versions of PC-HFDL to System Table #47. The numbers changed to frequencies on both.
I make no other guarantees, because it has not been tested on anyone else's machine. Use at your own risk. It won't hurt your computer, but it might not update PC-HFDL. It should be downloaded as a binary file, and saved anywhere convenient.
In order to use it, first close PC-HFDL. Find the PC-HFDL program directory, go to the folder named "configs," and rename the existing PCHFDL.DAT to something else. Copy this new one in, and rename it PCHFDL.DAT. Start PC-HFDL and pray. If frequencies appear instead of numbers, it worked.
If it didn't work, close PC-HFDL again, delete PCHFDL.DAT, and rename the old one back to that name. Then start PC-HFDL back up.
The link is:
http://www.ominous-valve.com/pchfdl47.dat