Operation manual (No schematic) for S-107 Mark II shortwave receiver.
Compliments of Dean Hemphill, K5DH.

Schematic for S-107 Mark II shortwave receiver.
Compliments of J.

Hallicrafters S-107 Notes from Tom, N4TL.

There are three types of S-107 radios, all use 8 tubes. S-107, S-107 Mark 1, S-107 Mark 2.

Tubes used in the three versions are as follows.

Mixer, IF, IF, ANL/DET, OSC, AUDIO/BFO,AUDIO OUT, RECTIFIER
S-107 :6BA6, 6BA6, 6BA6, 6H6, 6C4, 6SC7, 6K6, 5Y3
S-107 M1:6BA6, 6BA6, 6BA6, 6AL5, 6C4, 12AX7, 6K6, 5Y3
S-107 M2:6BA6, 6BA6, 6BA6, 6AL5, 6C4, 12AX7, 6AQ5, 5Y3

The S-107 and S-107 Mark one have a tone switch on the front. Old type headphone jacks on the back and a RCA phono jack input on the back.

The S-107 Mark two has a 1/4 inch headphone jack on the front and no tone switch. It also has an audio output RCA jack on the back.

The radio has two I.F. amplifier tubes. The AGC does not have enough range for very strong signals. So for strong signals, it is necessary to turn down the Sensitivity control to reduce distortion.

The radio also will receive SSB signals by setting the sensitivity control at about half level and turning on the CW switch. Tune on both sides of the SSB signal until the audio sounds okay. On one side it will not be clear and on the other side it is possible to understand what is being said.

Power used, measured on a Mark 2.
120 VAC, 50.8 Watts
105 VAC, 41.2 Watts

With a solid state 5Y3 tube
120 VAC, 39.6 Watts.
105 VAC, 30.6 Watts.