Newbie's First Questions RCA TS 721 Restoration

[Chris K]

Originally Posted by Electronic M

If it's a working generator odds are it will work for audio IF signal injection...IIRC a friend of mine has the same generator and has used it for FM work. You can check it by using an FM radio set to a dead channel in the 88-95MHz range and trying to tune the generator to make a signal in that range. If the FM radio tunes it then there should be enough FM slop in the generator for it to work with TV audio.

Before you start with IF injection first try audio injection at the first audio stage grid. That knight generator should have an audio output you can use. If the set passes audio from the 1st audio grid decently then IF injection is the next troubleshooting step. If it doesn't pass audio injected at the 1st audio grid then troubleshoot the audio stages and make them work before messing with the audio IF.

We can walk you through audio IF injection if you end up needing to do it.

So my RF generator is set at 21.25MHz. The grid on the 1st audio tube, 6AT6, is pin 1. Do I need to ground the black generator output lead or just touch pin 1 of the 6AT6 with the red lead from the Knight? Sorry for the very basic questions here but this is virgin soil for me!