Scopex 4D 10 oscilloscope. - UK Vintage Radio Repair and Restoration Discussion Forum

fast eddieg · 19th May 2017, 7:51 pm

I will try again to enter a thread. Last time I tried I hit a key and it all vanished.

I would like some help with my Scopex oscilloscope 4D10, which I have the circuit diagram for. The scope trace just went dead while in use. The only sign of a trace now is when turned off the spot moves to the tube centre just like an old CRT TV. The circuit board all looks fine and clean and I do get -1000v on the EHT at D607. I am reluctant to go poking about without some direction, so look forward to all your comments and help for a learner. Thanks Ed.

WaveyDipole · 19th May 2017, 9:04 pm

First thing to check is usually is all PSU line voltages. You mentioned you checked HV and you have -1000v, but have you checked all of the low voltage lines? Are they consistent with what the service manual states they should be?

19th May 2017, 7:51 pm	#1
fast eddieg Retired Dormant Member Join Date: May 2017 Location: Blackpool, Lancashire, UK. Posts: 1	Scopex 4D 10 oscilloscope. I will try again to enter a thread. Last time I tried I hit a key and it all vanished. I would like some help with my Scopex oscilloscope 4D10, which I have the circuit diagram for. The scope trace just went dead while in use. The only sign of a trace now is when turned off the spot moves to the tube centre just like an old CRT TV. The circuit board all looks fine and clean and I do get -1000v on the EHT at D607. I am reluctant to go poking about without some direction, so look forward to all your comments and help for a learner. Thanks Ed.

19th May 2017, 9:04 pm	#2
WaveyDipole Nonode Join Date: Mar 2013 Location: Leicester, UK Posts: 2,535	Re: Scopex 4D 10 oscilloscope. First thing to check is usually is all PSU line voltages. You mentioned you checked HV and you have -1000v, but have you checked all of the low voltage lines? Are they consistent with what the service manual states they should be?