I’m like yourself, this has not been one of my strong areas of expertise. But as a result of your query, I am now learning fast.
Much written On-line on this subject. The onr thing I will say upfront is always conect to your radio using a Capacitor inline with your Probe. This to keep you from smoking your Signal Generator. Some Signal Generators already have one such Capacitor installed internally in the Signal Generator itself. If your unit has such an internal Capacitor, be certain to replace it, A capacitor around .01-.5 mF will be sufficient. Also as your unit is an older one, make certain it is Calibrated accurately. Your unit is also RF and Audio Frequency capable, so make certain you set it up properly when working on either the Front End or the Output End of the Radio. Hope this information helps.
Elements of Radio Servicing, below is a good resource. Pages 21-48