Rca chro-bar generator manual?

[radioal]

I just scored an rca bar/dot/chroma generator at the Shelby hamfest. It is a model wr-502a. Does anyone know where I could find a manual or a scan of one for it? It's a pretty neat looking portable unit. Looking at ads for it in old magazines, it appears that there should be some additional alligator clip leads coming from the left side.

Al

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