UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Scopex 4D-25 Oscilloscope Repair Help

OldTechFan96 · 22nd Sep 2017, 10:23 am

I should have better explained my previous post.

The black wire was connected to the scope without a problem.

I measured the resistance from the chassis to the landing point of the transformer wires on the PCB. I had the black probe to the chassis and the red probe to the landing point. Here are the results:

Yellow - O/L
Blue - 9.4M ohms
Pink 1 - 34.5M ohms
Pink 2 - O/L

I then swapped my probes around (red to chassis and black to the landing point) and measured the same points:

Yellow - 11.8M ohms
Blue - O/L
Pink 1 - 2.6M ohms
Pink 2 - 15M ohms

Ignore what I said about failed diodes.

22nd Sep 2017, 10:23 am	#31
OldTechFan96 Octode Join Date: Jul 2017 Location: Newcastle Upon Tyne, Tyne & Wear, UK. Posts: 1,187	Re: Scopex 4D-25 Oscilloscope Repair Help I should have better explained my previous post. The black wire was connected to the scope without a problem. I measured the resistance from the chassis to the landing point of the transformer wires on the PCB. I had the black probe to the chassis and the red probe to the landing point. Here are the results: Yellow - O/L Blue - 9.4M ohms Pink 1 - 34.5M ohms Pink 2 - O/L I then swapped my probes around (red to chassis and black to the landing point) and measured the same points: Yellow - 11.8M ohms Blue - O/L Pink 1 - 2.6M ohms Pink 2 - 15M ohms Ignore what I said about failed diodes.