Thanks to Owner-Manuals.com! This manual was exactly what I needed. As Amana was purchased by Maytag and later by Whirlpool, there was no way to receive it from their websites. I was lucky to find this resource.
Great to be able to set channels again, on an old but stoll fine working TV
Text excerpt from page 39 (click to view)
DOUBLER
The Doubler replicates the input in another 2 voices and adds some detune, delay and feedback for the generated replicas. This creates rich chorus type effects as well as stereo enhancing and harmonic enriching effects. The Doubler is offered in Mono, Mono-to-Stereo and Stereo. It can go from very subtle to extreme effects. MIX: Range: 0 to 100; Default 50 This sets the balance between Wet and Dry. A 0 setting gives a 100% Dry signal 100 gives a 100% Wet signal. At 50, the Wet and Dry paths mixed are mixed evenly at -3dB. DETUNE: 0 to 25 Cents; Default: 8 This is the amount of detuned chorus effect, in cents, that the Doubler creates. DELAY: 12 to 100ms; Default: 11.3ms This is the length of the Delay effect added to the signal. FEEDBACK: 0 to 100; Default: 0 Feedback controls the amount of energy fed back from the voices� output back to its input. STEREO: 0 to100; Default: 50 At a setting of 100 the replicas are fully panned to left and right. At zero the replicas are panned exactly to center.