Note: Q3-C is used as shorthand notation for transistor Q3, the collector terminal.

The only other points worth mentioning here are that the output of the VCO (IC17-3) should be at least 5 volts p-p and the ramp control circuit can be disconnected from the enable switch by means of W12. With W12 cut a grounded test lead connected to the square end of the jumper can be used to simulate the action of Q4. This procedure is handy when the voltage readings on Q3-C check but those on IC17-5 do not. If the above test yields good readings on IC17-5 and the same readings were bad before cutting W12, then Q4 is leaky and must be replaced.

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