McMartin Reciever model TR-E5 need wiring diagram and operation manual

this unit has an antannae on the back a head phone jack an audio output jack,and a switch that says regular or special.
and one power/volume knob on the front
It powers on and sound comes from the speaker , my question is where on the circuit board can i input audio signal to.
the circuit board mcmartin p/n #550179,reciever

thankyou for your time directing me to this units functions or any help would be great on where to input the audio signal to its amplifier ..
David ;)