I have this monitor, which I think is a Commodore 64 monitor.
Not really. And especially not for the C64.
The screen was manufactured in Taiwan (*1) for/by Philips. It was widely sold as a monochrome screen to many countries.
What is true is, that Commodore OEMed it ca. 1985 as 1901(*2) or later 75BM13 (*3) for/with the PC10/20/... series (*4) of IBM compatible computers equipped with their AGA card (*3), a CGA / MDA / Hercules compatible adapter.
I would like to connect it to a pc.
It is already a PC one - for MDA cards/output.
- monochrome at
- 18.432 kHz with an
- effective resolution of 720x350 pixels and
- analogue intensity of
- 4 levels (used by MDA).
While MDA required 720 pixels at a 16.25 MHz pixel clock (video bandwith) Commodore speced the monitor at 800 and 20 MHz.
The only difference to a standard IBM compatible screen is that a DIN plug is used instead of a DE-9S.
Anyone know how to convert VGA or HDMI to this connector format?
Nope. I bet you would as well not like the loss of information due the downscaling.
I've tried searching, but so far I've only found solutions for hooking a C64 up with a VGA monitor, which is kind of the opposite of what I'm aiming for.
But that's what the usual way is: using older output generators, like a C64, with modern displays.
Now, widening up a bit why not use either an old PC, or if it has to be the new one, why not add an old graphics card to your new PC?
There are a large number of USB to ISA boards, ranging from hobbyist projects to commercial products, offering anywhere between a single slot or 8 slots.
Heck, there are even PCIe to ISA bridges except they are usually a bit expensive.
*1 - Legally, going by the FCC ID BOU, by Philips Consumer Lifestyle of Hong Kong.
*2 - Not to be confused with the 1901 colour monitor, based on a Thomson model, that got sold with C128 and early PC10 (for CGA Mode).
*3 - While 75BM13 sounds like directly taken form Philip's name for the green version BM7513, Commodore used it (only) for the amber one.
*4 - You may want to take a look at the German Wiki entry for the PC10, containing a bit more information, as these machines were not only developed at Commodore Braunschweig, but also quite popular as 'high quality' clones.
*5 - Advanced Graphics Architecture - not to be confused with the later Amiga Chipset of the same name - which got in turn named AA in Germany :))