
See the full post with more images and descriptions on Unidentified Sound Object. Also check out this post.
Pictured here:
RACK 2
* Brüel & Kjær 1011 beat oscillator
* 6 Wavetek 110 oscillators
* 2 Wavetek 115 oscillators
* Heathkit AG 10 oscillator
* General Radio 1398-A tone burst generator

* Unit with 7 slots:
* 2 ring modulators (made by RAI)
* 1 amplitude selector (made by RAI)
* 2 ring modulators for the frequency transposer (made by RAI)
* 1 electronic selector switch (made by RAI)
* 1 empty
* Dynamic modulator (made by RAI)
* Amplitude selector (made by RAI)
* Frequency transposer (made by RAI)