UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Restoring a CP110, tube life after regeneration?

3CX15000A7 · 25th Mar 2021, 11:42 am

For vertical: In the schematic I see only +140V (is OK on DC meter) and +32V , both seem to come directly from the main PSU. The +32V has a ripple of 1V pk-pk measured at C2574. Measuring with the scope at "33" (C2589) cleary shows some bending on the start/end of the line.

For +210V (and +140V) I will make some scope measurement photos. I have the idea the color isn't very pure because of the varying +210V on the cut-off circuit. Also strange is that I cannot crank the G2 to the point you get the lines and the white screen. Maybe also an indication for a bad LOPT . .
HT otherwise seems stable, picture sizes doesn't change really with varying content and no blooming.

I have to say, this set is misused, the beam limiter was bypassed on some way it wasn'n functional anymore. I found out after rejuvenating the tube that whites where extreme bright and flashing. Maybe this damaged the LOPT and some other stuff . .

25th Mar 2021, 11:42 am	#9
3CX15000A7 Tetrode Join Date: Dec 2019 Location: Bergen op Zoom, Netherlands Posts: 65	Re: Restoring a CP110, tube life after regeneration? For vertical: In the schematic I see only +140V (is OK on DC meter) and +32V , both seem to come directly from the main PSU. The +32V has a ripple of 1V pk-pk measured at C2574. Measuring with the scope at "33" (C2589) cleary shows some bending on the start/end of the line. For +210V (and +140V) I will make some scope measurement photos. I have the idea the color isn't very pure because of the varying +210V on the cut-off circuit. Also strange is that I cannot crank the G2 to the point you get the lines and the white screen. Maybe also an indication for a bad LOPT . . HT otherwise seems stable, picture sizes doesn't change really with varying content and no blooming. I have to say, this set is misused, the beam limiter was bypassed on some way it wasn'n functional anymore. I found out after rejuvenating the tube that whites where extreme bright and flashing. Maybe this damaged the LOPT and some other stuff . .