A 40-year old homemade Volt-Ohmmeter was refurbished using a PICAXE instead of RTL logic.
It has 8 voltage and 14 resistance 5-15 ranges, selected by relays.
There is a single control, a voltage-ohm switch.
It uses a rectifier in the meter amplifier feedback to measure voltages
of either polarity or AC without switching. AC gain is modified automatically
to correct for average-RMS of a sine-wave.
Indicator lamps show the range in use and the mode: Positive, Negative or AC
voltage, or Kilo or Megohm resistance. For details see:
http://projects.worsleyassociates.com/Auto_VTVM/index.html?
It has 8 voltage and 14 resistance 5-15 ranges, selected by relays.
There is a single control, a voltage-ohm switch.
It uses a rectifier in the meter amplifier feedback to measure voltages
of either polarity or AC without switching. AC gain is modified automatically
to correct for average-RMS of a sine-wave.
Indicator lamps show the range in use and the mode: Positive, Negative or AC
voltage, or Kilo or Megohm resistance. For details see:
http://projects.worsleyassociates.com/Auto_VTVM/index.html?