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Early Electronic Television
General Electric HM-171 and HM-185 Tube List
Television: Three channel (50-90 mHz) superhetrodyne. 5 inch CRT (5BP4) tetrode. Electrostatic focus and deflection, approx. 30 degrees.
Function
Quan
.
Type
Notes
Oscillator/Mixer
1
6F8
Video IF Amplifier
2
6AB7
Video (9.5-12.75 mHz), audio (8.25 mHz)
Video IF Amplifier
1
6AC7
Video detector/amplifier
1
6F8
Video output/sync separator
1
6F8
Horizontal (line) oscillator
1
6N7
Horizontal (line) output
1
6F8
Vertical (frame) oscillator
1
6N7
Vertical (frame) output
1
6F8
Audio IF amplifier
2
6SK7
8.25 mHz
Audio detector
1
6H6
HM-171 only
Audio detector/amplifier
1
6SQ7
HM-185 only
Audio Output
1
6V6
HM-185 only
Rectifier (HT)
1
5U4
High Voltage (EHT)
1
2X2
2500 VDC
Service notes
Technical information