Mitsubishi M70 & M700 Display Upgrade

Your CRT is dim, flickering, or has died completely. Here's how to replace it with an LCD that actually works — and costs less than you think.

Why the M70/M700 CRT fails (and why now)

The Mitsubishi M70 and M700 series controllers are solid pieces of hardware. The CRT monitor attached to them? Not so much.

If your machine is 10+ years old — which most are — the CRT is living on borrowed time. Here's what typically goes wrong:

Dim or flickering image. The high-voltage section degrades. Sometimes it's intermittent; sometimes it gets progressively worse over weeks.
No display at all. You power on, fans spin, but the screen stays dark. Usually the flyback transformer or the CRT neck board.
Color shift or geometry problems. The image is stretched, or the colors are off. Annoying for setup, dangerous for precision work.
Physical bulk. A CRT is heavy. If you've ever had to remove one, you know exactly what I mean.

The M70 and M700 are widely used on milling machines, machining centers, and some turning centers. They're good controllers. Replacing the entire CNC just because the monitor died is — honestly — a terrible financial decision. A retrofit LCD kit costs a fraction of a new controller and takes less than an hour to install.

Is your machine compatible?

This is the first question everyone asks, and the answer is: almost certainly yes. But let's be specific.

Mitsubishi M70 Series

The M70 series uses a standard 9-inch or 10-inch CRT with a Mitsubishi-specific signal interface. The retrofit kit replaces the entire monitor assembly while keeping your existing CNC controller untouched. No parameters to change. No software updates. It just works.

Mitsubishi M700 Series

The M700 is the newer series (though "newer" is relative here). Same situation — the CRT fails, the controller is fine. The LCD retrofit kit for M700 handles the signal conversion internally.

Not sure which series you have? Look at the controller model plate. If it says M70, M700, M700V, or M70V — we cover it. If you're still not sure, send us a photo of the controller front panel and we'll tell you within a few hours.

What's actually in the retrofit kit

A complete LCD upgrade kit isn't just "a screen in a box." Here's what you're getting:

Component	What it does
LCD panel (10.4" TFT)	Replaces the CRT. 800×600 resolution, LED backlight, 50,000+ hour rated life.
Signal converter board	Translates the Mitsubishi CRT signal to drive the LCD. Pre-configured, no setup needed.
Mounting brackets	Adapts the new LCD to fit the original cutout. No drilling, no fabrication.
Power cable	Draws power from the same source the CRT used. No new wiring to the mains.
Installation guide	Step-by-step with photos. Written for a machinist, not an electronics engineer.

Installation — yes, you can do this yourself

I've seen a lot of people assume this requires a service technician. It doesn't. If you can use a screwdriver and read a wiring diagram, you can do this install.

Before you start

Power down the machine. Lock out the main disconnect. Wait 5 minutes — CRTs hold high voltage even after power-off.
Take a photo of the existing wiring. Before you disconnect anything. Trust me on this.
Check the model plate. Confirm it's M70 or M700 series. (If it's not, the kit won't fit — don't guess.)

Removing the old CRT

Remove the front bezel (usually 4–6 screws).
Disconnect the CRT video signal cable from the controller side.
Disconnect the power cable (follow it to the CRT side).
Unscrew the CRT mounting brackets and carefully lift it out. It's heavier than it looks.

Installing the LCD

Mount the LCD panel into the existing cutout using the supplied brackets. It should fit exactly where the CRT was.
Connect the signal converter board (it's pre-wired, just plug it in).
Connect power. The LCD draws less power than the CRT, so if the old fuse was borderline, this might actually solve intermittent power issues too.
Power on and test before you put the bezel back on. Make sure the image is stable and the touch function (if equipped) works across the entire screen.
Reinstall the bezel. Done.

Time check: Most installs take 45–90 minutes. The first one takes longer because you're being careful. The second one (if you have multiple machines) takes half that.

Cost: repair vs. replace vs. retrofit

This is where the financial argument gets very clear, very fast.

Option	Typical Cost (USD)	Downtime	Expected Life
CRT repair (if even possible)	$300–$600	1–2 weeks (shipping)	1–3 years (it'll fail again)
New CRT replacement	$800–$1,200	1–2 weeks	3–5 years
New CNC controller	$8,000–$15,000	2–4 weeks	10+ years
LCD retrofit kit	$450–$750	<1 day	10+ years

The retrofit kit wins on every dimension except one: if your CNC controller itself is also 20 years old and failing, then maybe it's time for a full upgrade. But if the controller is fine and it's just the monitor — retrofit is the answer.

M70 vs. M700 — any difference for the retrofit?

Good question. The short answer: the kit is slightly different because the signal pinout varies between M70 and M700. But the installation process is essentially identical.

If you order from us, we figure out the correct kit based on the model number you provide. You don't need to worry about the pinout — that's our problem, not yours.

Frequently Asked Questions

Will this void my machine warranty?

If your machine is still under warranty (unlikely for M70/M700 — these are mature series), then yes, modifying the monitor could theoretically affect it. In practice, most M70/M700 machines are well out of warranty. If you're unsure, check with your machine tool builder.

Does the touch screen still work after the upgrade?

If your original setup had touch screen, the retrofit LCD kit preserves that function. If it was a non-touch CRT, the LCD also comes in non-touch. We match what you had — not a generic "one size fits all" approach.

What if I have a different brand controller (Fanuc, Siemens) in addition to Mitsubishi?

We make retrofit kits for those too — Fanuc, Siemens, and others. If your shop has a mix, ask us about a multi-kit discount. We've supplied shops with 10+ machines on different controllers and set them up with the right kit for each.

How long does the LCD backlight last?

The LED backlight in our LCD panels is rated for 50,000+ hours. That's roughly 17 years at 8 hours a day. Your next problem will not be the backlight.

Can I buy just the LCD panel and reuse my existing bracket?

Sometimes. It depends on how the original mounting was done. In most cases, the full kit (panel + bracket + converter) is the safer bet because everything is pre-tested together. If you're handy with fabrication, we can sell you just the panel — but we'll warn you upfront that signal timing mismatches are annoying to debug.

当CRT黑屏时，您的M70/M700还能撑多久？

简单说：不要等到完全黑屏才行动。CRT的衰退是有预兆的——画面变暗、开始闪烁、偶尔花屏。这些都是"我快不行了"的信号。

我们见过太多工厂在周五下午CRT彻底熄灭，然后整台机床停到周一供应商才能来修。如果提前一周行动，一个快递就能把LCD套件送到，周六维护时顺手换上，周一正常开工。

Need a quote for your M70 or M700?

Send us your controller model number (or a photo of the front panel). We'll confirm compatibility and give you a firm price within 24 hours.

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