Which retro personal computers, if any, can use a modern day VGA monitor?

Question

I play around with emulators, but I would love to go back to my roots, with physical ZX81, BBC Micro, Amiga, etc.

Unfortunately, those all require a CRT monitor, or a TV, as output. I suppose that I could buy a cheap one on AliExpress.

I am curious as to which, if any, home or business computer from "the golden age of retro" (the '80s, for me) could be used with an analogue VGA monitor, without the use of modern day upscalers, such as the Framemeister.

There are a number of questions which discuss adapters: Atari ST and C64, scaler with customisable horizontal sampling, Amiga, pre-VGA PCs. Many of the adapters mentioned there will work with other computers of the time. — Stephen Kitt, Oct 31 '19 at 08:33
Wow! Thanks *very much! I also asked for a cheap PAL input TV/monitor on Hardware Recommendations. — Mawg says reinstate Monica, Oct 31 '19 at 08:37
For one, the question is way too broad, ranging from TV output like Z81 all the way to machines that do already output in the VGA range (Amiga). Next it's missing any research effort, as keying in "VGA HDMI Converter" will show the desired result. Which brings the last point: No buy recomendations on RC.SE. — Raffzahn, Oct 31 '19 at 08:49
"...or even HDMI" considering that HDMI didn't exist in the 20th century... — Bruce Abbott, Oct 31 '19 at 09:18
@BruceAbbott surely "could be used with HDMI" would include machines that could be connected to HDMI via a suitable adapter. — nekomatic, Oct 31 '19 at 09:20
If we are talking 'suitable adapter' then the answer is - all of them! — Bruce Abbott, Oct 31 '19 at 09:22
Each current TV with a composite input (yellow cinch) may accept home computers with a composite output. YMMV For example, some ZX81 clones have no reference black which irritates the TV. — the busybee, Oct 31 '19 at 11:35
Oh, and SCART inputs were once designed to accept RGB signals... — the busybee, Oct 31 '19 at 11:42
At best, this is a list question. At worst, the answer is "all of them". — Chenmunka, Oct 31 '19 at 11:59
@Mawg because all mainstream computers produced in the 80s can be connected to a modern screen (there is sufficient interest for adapters to be available for all of them). That’s why this is a list question: an answer would list all mainstream 80s computers, with their variants, and for each of them, explain how to connect them to a modern screen. — Stephen Kitt, Oct 31 '19 at 13:46
Thanks for that (+1). I may well ask a new question, specific to a single PC — Mawg says reinstate Monica, Oct 31 '19 at 14:36
Atari ST can connect to VGA with its monochrome 640x400 resolution. Requires only the adapter to its exotic connector. — Patrick Schlüter, Nov 11 '20 at 13:47

score 5 · Accepted Answer · answered Oct 31 '19 at 10:45

5

A few 'home' computers from the '80s could output a VGA signal, including:-

Acorn Archimedes
Commodore Amiga (with Flicker Fixer)
PC clones that had VGA on board or could take a VGA card (eg. Sinclair PC200)

But for the vast majority that didn't produce a VGA signal you need an upscaler. Computers that only had RF output, such as the ZX81, ZX Spectrum, Tandy Color Computer etc. will need modifications to get composite or RGB output.

Cheap composite to VGA upscalers are available on eBay (eg.AV to VGA HD Converter). Alternatively you could just use a small LCD TV (which often also have VGA input).

For RGB to VGA the cheapest solution is the Gonbes GBS8200. Like most upscalers it has some artifacting and frame lag, but this can be reduced by overriding the onboard controller with a custom programmed MCU.

answered Oct 31 '19 at 10:45

Bruce Abbott

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I've had great luck using modern TV's that accept YPbPr component input. I was able to take the Composite video from my Laser 128 and connect it directly to the Y (Luma) and display black and white without any problem. I suspect this is a function of how good the TV is, and you sacrifice color... but it does seem to work. – Geo... Nov 01 '19 at 15:59
@Geo... I also use component input (YPbPr) on modern displays for retro machines. It's automatically 15.7kHz compatible. You just need a (relatively) simple converter to go from RGB to component, vice needing to upscale to higher scan rates. – Brian H Nov 01 '19 at 21:07
My LED TV has component inputs but they only work in interlace. So I bought a component to HDMI converter - same problem. – Bruce Abbott Nov 02 '19 at 01:00
“a small LCD TV” which is practically the same as “a small LCD monitor”, besides having some adapters and a TV tuner included. The TVs I encountered all had VGA and RGB Scart, I have the suspicion that most TV vendors use the same supplier for the adapter technology, so that’s the simplest solution. Especially for the Amiga, I’d use a device with RGB Scart input rather than a Flicker Fixer + VGA… – Holger Dec 12 '19 at 10:37
@Holger You must live in Europe. Unfortunately in other parts of the world SCART is virtually non-existent. I was lucky enough to find a Samsung Syncmaster 940mw at a charity shop here in New Zealand. Unfortunately the upscaler in it is not very good - it appears to convert the RGB to YUV with low resolution, and even after tweaking the hidden upscalar parameters it still has too much edge 'enhancement' (partially solved by putting capacitors across the RGB inputs to reduce bandwidth). – Bruce Abbott Dec 12 '19 at 17:58
@BruceAbbott indeed, but since you can order via internet from all over the world, this shouldn’t matter much. In the end, they all are likely manufactured in the same Asian factory… – Holger Dec 13 '19 at 06:59
@Holger Yeah, except importing a TV might not be very practical due to shipping costs, customs duties, loss of warranty and finding a vendor who is willing to export. I just searched eBay and found a nice second hand 32" TV with SCART - 100GBP shipping to NZ, ouch! But the real killer:- "UK Bidders only. Relisted due to overseas bidder winning." - don't offer worldwide shipping if you don't want to ship overseas!!! – Bruce Abbott Dec 13 '19 at 10:31
I apologise for editing the question so the second part of your answer is less relevant, but I was so impressed by the first half that I wanted the question to be improved to match. – Mark Williams Nov 06 '20 at 18:44
One more unpleasant surprise one could "enjoy" with SCART and LCD TVs is that certain retro computers did not follow the PAL standard close enough (guess NTSC could be susceptible to the same problem, but haven't seen any proofs). Old CRT TVs with analog circuitry were sufficiently tolerant to that, but newer LCD ones quite frequently become very picky and refused to show a stable synced picture. – DmytroL Nov 12 '20 at 17:39

Which retro personal computers, if any, can use a modern day VGA monitor?

1 Answers1