Darry might know. Which adapters have you tried ? Which pin is missing ?
Pin 5 is not used so if missing is no big deal but if it Pin 15 that is for part of the DDC signaling which is probably required for the converter to know what resolutions the monitor can handle iirc.
https://en.wikipedia.org/wiki/VGA_connector
Have a Startech HD2VGAE2 that works OK from my newest video card to an old Dell LCD with just VGA input. Never tried it with a CRT....
added and after thought: does the video card (or device) have a DVI-I output ? Those can be directly converted to VGA without issue with simple passive converter.
If all you have is HDMI am curious what are you trying to feed the CRT from ?
My newest (2018 so not too old) Nvidia card has multi ports: DVI-I, DVI-D, HDMI and Display ports but bought the exact model on purpose because wanted those extra output features.....

Horun wrote on 2021-01-09, 01:54:

Which adapters have you tried ?

These two:

Horun wrote on 2021-01-09, 01:54:

Which pin is missing ?

The 9th pin.

Horun wrote on 2021-01-09, 01:54:

Have a Startech HD2VGAE2 that works OK from my newest video card to an old Dell LCD with just VGA input. Never tried it with a CRT....

The Startech HD2VGAE2 looks like the same white-labelled converter that I have.

Horun wrote on 2021-01-09, 01:54:

does the video card (or device) have a DVI-I output ?

It doesn't have DVI-I as far as I know. I intend to use the HDMI cable with a lot of different devices.

Horun wrote on 2021-01-09, 01:54:

If all you have is HDMI am curious what are you trying to feed the CRT from ?

Different laptops. In this case I tried a 2012 MacBook Retina and a regular Windows 10 laptop.

Ahh Your CRT monitor only supports to 1024x768 @ 60Hz, did you set the resolution to that or below before trying the monitor as an External on the laptops ?
Because the monitor is not HDCP compliant those cheaper solutions will not work if you try to feed a signal that requires HDCP handshaking including 720p mode (1280x720) AFAIK

Horun wrote on 2021-01-09, 03:00:

Ahh Your CRT monitor only supports to 1024x768 @ 60Hz, did you set the resolution to that or below before trying the monitor as an External on the laptops ?
Because the monitor is not HDCP compliant those cheaper solutions will not work if you try to feed a signal that requires HDCP handshaking including 720p mode (1280x720) AFAIK

I didn't change the solution. It's not really viable because I need to be able to plug any laptop in and use the external monitor without having to first change the native resolution of the laptop.

Is there any way to achieve the desired result with a signal converter?

The Aten VC812 has built in selectable down conversion but costs about $150. It does support 1024x768 @60Hz output for your CRT.
https://www.aten.com/global/en/products/profe … nverters/vc812/
You can read the manuals and see if it matches what you are looking for....

Horun wrote on 2021-01-09, 16:04:

The Aten VC812 has built in selectable down conversion but costs about $150. It does support 1024x768 @60Hz output for your CRT.
https://www.aten.com/global/en/products/profe … nverters/vc812/
You can read the manuals and see if it matches what you are looking for....

Alright, great.

Thanks for the help. Much appreciated! 😀