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The synchroguide circuit is basically a Hartley ocsilolator followed by a wave shaping coil. The oscillator is tuned to the horizontal scan frequency; 15,750. The wave shaping coil is tuned to twice the frequency.
One way to get the circuit close is to short the wave shaping coil with a clip lead. Center the horizontal hold control and tune the oscillator coil for a normal picture. Then remove the short and tune the wave shaping coil for a stable picture, without touching any of the previous adjustments. Once you get the circuit tuned, you can fine tune it by connecting a scope in series with a resistor, 27 K or so, to the point on the oscillator coil where the resistor and capacitor meet. Then adjust the wave shape to where the peak is equal to, or about 10% higher than the hump for best stability. That will not require much adjustment.
If you are not sure which end of the coil is the oscillator, it will be the only one that has effect when the wave shaping coil is shorted.
If that does not work, it will point to the source of the trouble.
Don
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