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MotorBikeLes · 13th Jan 2018, 9:32 pm

This sounds a bit like an unblanking problem to me.
A WME-Bill said, make sure STABILITY is set fully over to ensure trace will run. You see some initial timebase display, but it then disappears. Set your timebase speed very slow, say 0.1 secs per division. Connect a voltmeter, PREFERABLY ANALOGUE**, between one X-plate connection (collector of TR113 or TR114. You should see the pointer go from 0 to to about 50v, then quickly back again. Similar on each X output point. If that is happening, but you see nothing happening on the screen, then the X amp is OK, but the unblanking is not. Check TR109, Tr111 and TR115, replacement being easy as Bill said.
**If you don't have an analogue meter, set timebase speed to 1sec/div, and MAYBE a DVM will show the same, but it will take 10 seconds to rise fron 0v to 50v.
Les.

13th Jan 2018, 9:32 pm	#10
MotorBikeLes Nonode Join Date: Dec 2012 Location: Kirk Michael, Isle of Man Posts: 2,350	Re: New member and a Telequipment D54 This sounds a bit like an unblanking problem to me. A WME-Bill said, make sure STABILITY is set fully over to ensure trace will run. You see some initial timebase display, but it then disappears. Set your timebase speed very slow, say 0.1 secs per division. Connect a voltmeter, PREFERABLY ANALOGUE, between one X-plate connection (collector of TR113 or TR114. You should see the pointer go from 0 to to about 50v, then quickly back again. Similar on each X output point. If that is happening, but you see nothing happening on the screen, then the X amp is OK, but the unblanking is not. Check TR109, Tr111 and TR115, replacement being easy as Bill said. If you don't have an analogue meter, set timebase speed to 1sec/div, and MAYBE a DVM will show the same, but it will take 10 seconds to rise fron 0v to 50v. Les.