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Heatercathodeshort · 5th Oct 2017, 8:12 am

It wasn't exactly common but I did experience a few. The actual breakdown was caused by the connecting leads becoming detached or going high resistance from the 'element' itself. The Thorn 900/950 comes to mind.

With a complete O/C the frame collapse tended to have a kink in the straight line due to line waveform being allowed to enter the low resistance frame coils due to the O/C connection. You will only see this effect when the O/C occurs on the secondary of the output transformer, the scan coil connections or the thermistor being the usual cause. J.

5th Oct 2017, 8:12 am	#31
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Frame cramp Baird M676 help It wasn't exactly common but I did experience a few. The actual breakdown was caused by the connecting leads becoming detached or going high resistance from the 'element' itself. The Thorn 900/950 comes to mind. With a complete O/C the frame collapse tended to have a kink in the straight line due to line waveform being allowed to enter the low resistance frame coils due to the O/C connection. You will only see this effect when the O/C occurs on the secondary of the output transformer, the scan coil connections or the thermistor being the usual cause. J.