Labels:text | font | black and white | screenshot | printing | document OCR: MEMORIZE AND BURN The Red Boxes of the future won't be as simple as before. We reported in the last issue that the new Red Box tones A are 2200 and 1700 Hz. The old 2200 Hz Red Boxes must be modified by adding the extra 1700 Hz. oscillator. We have 9 Switch (OPTIONAL) pictured, for informational purposes only, a 1700 Hz. osc- illator. It is a simple matter to add this to the Red Boxes in Issue 16 or Issue 25. To add this to the Issue 16 Red 15K 100K Box, one would connect point A to V+ line after the on-off .. 01 002 B switch, just as the existing oscillator is now connected in that Box. Next, the output of the oscillator must have a 100K resistor added in series with the . 01 mfd. capacitor . 992 47K Add this 100K that is there now. Just break the line before or after the . 01 and insert ...
