The oscillator is not working, based on second radio test. Can someone explain to me the oscillator circuit in this radio re: troubleshooting?

Plate voltage (200) and screen voltages (100) are there, appear to fluctuate by about 25 to 50 volts higher at times. Pin 5 is positve.

:The oscillator is not working, based on second radio test. Can someone explain to me the oscillator circuit in this radio re: troubleshooting?
:

The oscillator is contained in the converter stage. This link has a basic trouble shooting and possible cause.

http://www.portabletubes.co.uk/sitefiles/restore.htm

Bottom of page. The converter stage #4