RVFM Electrometer, DC Amplifier

Designed for ease of use and superior performance while used for measurement of small current, small charge or time constant for RC experiments. Rotary switch of extremely high insulation resistance (>500GΩ) is employed to select resistors or capacitors, to discharge the capacitor or leave them open.

Typical half times for this unit, for the built in 1nF 100GO or 100nF 1GO RC pairs, are from 67 to 71 seconds against theoretical values of 69.3 seconds. Charge or current is tabulated on a table on front panel for easy reference.

• Measurement range from 1pA to 100nA, 0.1nC to 100nC
• 1V auxiliary output is provided for data-loggers
• Complete with a UHF male to 4mm plugs lead
• Professional electrometer IC
• Input leakage current for amplifier guaranteed less than 25fA
• Built in moving coil meter
• Analogue outputs available for dataloggers or external meter
• Input resistance over 1TΩ
• Selection of 1nF 1% or 100nF 2% capacitors
• Selection of 10MΩ 1%, 1GΩ 1% or 100GΩ 1% resistors
• x1 and x10 gain switch provides the decades between the built-in resistors
• Suitable for Key Stage 3+ (age 11 and above)