- Enter your meter reading (0 – 120) into the “Meter” box.
- Choose your Range Switch position in the drop-down box.
- Press the “Calculate Gm” button and read your micromhos score.
- Press “Reset” button to clear your entries or to start another calculation.
- Invalid entry ( meter > 120 ) will automatically reset the calculator.
- calculator works for all TV-7 models: TV-7/U, TV-7A/U, TV-7B/U, and TV-7D/U
- Range A on TV-7 is only used for emission testing of diodes and rectifiers — no mutual conductance reading exists. Therefore, I have omitted Range A from the calculator. The Range A meter reading is an arbitrary emission score that is evaluated in relation to the “Minimum Value” notation in the setup book.
- Range B signal voltage is 5.0v ac with bias 0 to -40 vdc
- Range C signal voltage is 5.0v ac with bias 0 to -40 vdc
- Range D signal voltage is 1.0v ac with bias 0 to -40 vdc
- Range E signal voltage is 0.5v ac (500 mV) with bias 0 to -40 vdc
- Range F signal voltage is 0.5v ac (500 mV) with bias 0 to -4 vdc. Range F is 0 to 30,000 micromhos, not 60,000 as reported elsewhere. Click to “Read the rest of this entry” below for details.
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