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In the Integrated Timer experiment in "Hands-On Radio" (Jun 2003 QST, page 59), the actions of the set and reset functions of the flip-flop are reversed. Correctly stated, when the set input (trigger comparator output) changes from low to high, Q goes low. When reset (threshold comparator output) changes from low to high, Q goes high.--Dan Ferreira, N1BMA

In "The Protector" schematic (Jun 2003 QST, Figure 1, page 56), resistor R13 (10 k ) was omitted. It should be in series with pin 2 of U2A (LM358) after the junction of R11, R12 and C3.--Arnaldo Drummond, PY5AQ