by Steven LeibsonAfter repairing and upgrading two Heathkit IM-2420 frequency counters and two HP 5314A frequency counters, I have developed a deep obsession with these instruments. I cleaned as much of the corrosion from the circuit board and the five socketed ICs on the circuit board as I could. Trionyx TR-1000 Frequency Counter. This 2-chip set makes an interesting comparison with the 1-chip Intersil ICM7226A frequency counter/timer used in the HP 5314A frequency counter that I discussed in my previous article. That’s close to what I paid for the TR-1000 frequency counter.