With your multimeter, confirm that you have ~2.3v DC on pins 1 and 2 of the 494. Also confirm that you have rail voltage on the first set of rectifiers.
If you have those, the peak to peak voltage on the rectifiers may be too much for the settings you used on the scope. Set it to the highest v/div and make sure that you have the probe set to 10x (if it has a switch). If you see horizontal lines above and below the reference line, turn the vertical amplifier to whatever it takes to get those vertical lines to ~±3 vertical divisions. Then turn the timebase until you have ~3-4 cycles on the display. This basic procedure is something you'll have to do on may repairs so try to remember it.
If you have those, the peak to peak voltage on the rectifiers may be too much for the settings you used on the scope. Set it to the highest v/div and make sure that you have the probe set to 10x (if it has a switch). If you see horizontal lines above and below the reference line, turn the vertical amplifier to whatever it takes to get those vertical lines to ~±3 vertical divisions. Then turn the timebase until you have ~3-4 cycles on the display. This basic procedure is something you'll have to do on may repairs so try to remember it.
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