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cakerack · 17th Apr 2021, 12:21 pm

Hi All

Sorry for the long delay in replying - I have been trying to find where this sync loss issue was being caused. So I managed to track it down to TR63 on the S2A module. Basically a hair dryer and a can of freezer was my friend there. I changes TR63 and TR64 for good measure and now the sync appears to be spot on.

So now to the other issue of the screen fading to the right hand side of the display (photo attached). If I have the scope on a fast timebase, its fine - which suggests to me (correct me if I'm wrong) that the fault ISN'T in the HT side of things. If I have it on a slow timebase, for instance 1mS, the trace barely gets 2 divisions across the screen. Set it to 100uS and the trace gets all the way across to the right of the display. Where do I start?!

Cheers

Sean

17th Apr 2021, 12:21 pm	#16
cakerack Diode Join Date: Mar 2021 Location: Richmond, North Yorkshire, UK. Posts: 8	Re: Telequipment D75 Scope Hi All Sorry for the long delay in replying - I have been trying to find where this sync loss issue was being caused. So I managed to track it down to TR63 on the S2A module. Basically a hair dryer and a can of freezer was my friend there. I changes TR63 and TR64 for good measure and now the sync appears to be spot on. So now to the other issue of the screen fading to the right hand side of the display (photo attached). If I have the scope on a fast timebase, its fine - which suggests to me (correct me if I'm wrong) that the fault ISN'T in the HT side of things. If I have it on a slow timebase, for instance 1mS, the trace barely gets 2 divisions across the screen. Set it to 100uS and the trace gets all the way across to the right of the display. Where do I start?! Cheers Sean Attached Thumbnails