The Model JH7500 and Model JH7501 from JH Technology Inc., Sarasota, FL, are DC-to-frequency converters that are used to totalize or integrate measurement signals such as flow or kilowatts. The Model JH7500 has output ranges to 10 kHz and the Model JH7501 has a relay contact output for electromechanical counters (F.S. pulse rates can be as low as 1.25 pulses/min.). Both converters offer input-output isolation, AC or DC power options, and a range of input choices, including 0–5 V, 0–10 V, 4–20 mA, and 0–1 mA DC.