Waveforms from the 4046 PLL

[Rydepier]

I thought perhaps these waveforms may be of interest. I have four sync signals each one squared off and 12 volts. The video line sync is extracted as normal and used to produce a 'frame' pulse using a monostable. The line sync pulses from the Nipkow disk are also used to produce a 'frame' pulse using a monostable.

I built the slightly modified club circuit for the PLL and motor driver, that includes a switch to allow the PLL to be disconnected from the motor driver. I find that the frame pulse is ideal to trigger the oscilloscope as it provides a steady uninterupted pulse.

In the traces below the blue trace is the Nipkow disk frame pulse and the red trace is the output from the PLL.

The first trace shows the PLL disconnected from the motor, but spinning slow.

The second trace shows the PLL connected , but the motor trying to reach the correct speed.

The last trace shows the PLL connected to the motor and spinning at the correct speed with frame lock.