1924 Crosley Radio Corp.; Cincinnati (OH) Broadcast Receiver - or past WW2 Tuner..This is a 1924 Crosley Model 52 AM receiver. It is battery powered, has 3 tubes, and is a regenerative receiver. The first tube is the regenerative detector, the second is an audio amplifier, and the third is a second audio amplifier. Tuning is accomplished by selecting one of 5 taps on the coil and then turning the large dial until the desired station is heard. Feedback for regenration is accomplished by pulling the knob to the upper right of the large dial in a out. Pulling it out increases the coupling and therefore the feedback. Optimum operating point for regeneration is just at the point of oscillation. The radio is similar to the 2-tube Crosley Model 51. The operating principle for both radios is the same - the only diffrence is that the Model 52 has one additional stage of audio amplification. The measurements are 13" x 6 1/2" x 6 3/4". 7lbs. The reciever has been tested and is in functioning working condition.