Problem Switching H/V yoke polarity on Sony PVM for CW/CCW tate – safe approach?

[Locutus73]

Hi everyone,

I’d like to ask for some advice regarding a setup I’m working on with Sony PVM monitors for tate gaming.

Until recently I was only using a Sony PVM-20M2MDE for everything (arcade + consoles), but I’ve just added a PVM-14M2MDE specifically for vertical (tate) games.







My idea is to keep the 14” permanently rotated 90° CCW, since:

• it looks much cleaner in my setup (only top/right side visible)
• it fits better aesthetically in my room
• when rotated CW I get a slight purity issue in one corner

However, I’ve run into the classic problem:

• some games (e.g. many CAVE shmups) require CCW rotation
• others (e.g. older Namco titles) require CW rotation

So ideally I’d like to switch between CCW 90 ↔ CW 90 without physically rotating the monitor.

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Proposed solution​

From what I understand, on CRTs this can be achieved by:

• inverting H+/H-
• and V+/V- at the yoke

This should result in a 180° image rotation, which—since the monitor is already physically at 90° CCW—effectively lets me switch between CCW and CW tate.

This is something commonly done on arcade monitors, so I’m not too concerned about the concept itself.

My idea was to implement it using:

• two DPDT ON-ON switches (one for H, one for V),
  or possibly a single DPDT x2 (ganged) switch

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Concern​

I’ve been advised against doing this with standard switches because:

• the horizontal deflection circuit involves high voltage pulses
• typical panel switches may not be suitable (arcing, insulation, etc.)

At the same time, I vaguely remember seeing similar mods discussed on the Internet, and possibly even some safer implementations.

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Questions​

1. Has anyone here implemented H/V inversion via switches on a PVM or arcade monitor?
2. Are there specific switch types (high insulation, industrial, etc.) that are considered safe for this?
3. Would a relay-based solution be more appropriate?
4. I also recall someone somewhere mentioning a protection circuit that ensures the circuit is never open (i.e. cuts power if switching state is invalid).
   Does anyone have details on that approach?
5. Any other safe / clean alternatives to achieve CCW ↔ CW switching without physically rotating the monitor?

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I’ll attach photos of the monitor in both CCW and CW orientations for context.

Thanks a lot in advance—any insight or experience would be really appreciated 🙏