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Thanks in advance.

The squished horizontal is due to low voltage on the 8.6V--in fact all the DC voltages are low by about 15%.
(I have read all the 2235 power supply problems and got the schematics in large format.)
I have extensively probed the power section before the CRT HV section.

i have replaced some caps.
When i unplug Q9070 the voltages are fine so i am looking in the section the follows the mosfet-bottom of the schematic and Q908.
VR943 is flaky and it is connected to Q944 which the table says is a SI NPN 625MW, TO-92, Manu part # is TO7391E2-this is a pretty general description!
Before i replace the VR943 i want to check Q944.
i (think) equivalents may be MPSA42, MPSA55, MPSA14, BC337, BC547B.

Can anyone definitively state the proper equivalent?

Eng,

Q944 is a 2N3565 (151-0432-00), 610-2N3565 Mouser part number. The zener can be replaced with a 78-BZX85B6V2 (Mouser part number).

Mark

Thanks.

On Fri, Feb 21, 2025 at 09:40 AM, Eng Heads wrote:

The squished horizontal is due to low voltage on the 8.6V--in fact all the DC
voltages are low by about 15%.

In the 22xx scope's power supply the 8.6V rail acts as a reference for all other voltages, so if 8.6V is low, all other rails will also be dragged down.