have a few but a bit scared to turn them on
my beeb monitor from 1985 got binned 1992 as it would hardly turn on
I ask as I have a few 8088 (286) PCs , one has composite out on the massive card too (with 5 1/4" disc 8272 FDC), so better to just use that....
turning on CGA / EGA / VGA '87 monitors?
- CMcDougall
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Re: turning on CGA / EGA / VGA '87 monitors?
For old equipment like radios and televisions with valves we normally "start them up" with a 75W light bulb in series. That way, if there is a huge short circuit then the power will be dissipated by the light bulb and not by the equipment under test. Of course, the monitor might not function properly in this setup.
But before that you should do a visual check of the components, especially capacitors and check with a multimeter if there is no short circuit.
But before that you should do a visual check of the components, especially capacitors and check with a multimeter if there is no short circuit.
FPGAtom: 512 KB RAM, Real Time Clock and 64 colours
MAN WOMAN
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- CMcDougall
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Re: turning on CGA / EGA / VGA '87 monitors?
thanks Roland!
good idea with light bulb
don't think they have old valves, sure the 386 monitor I took to bits to turn up brightness pot never had them, but that was 1992 & can't remember
might put them in middle of back garden with long lead, RCD safety plug & turn on 7m away & watch for a big bang or fizz noise
good idea with light bulb
don't think they have old valves, sure the 386 monitor I took to bits to turn up brightness pot never had them, but that was 1992 & can't remember
might put them in middle of back garden with long lead, RCD safety plug & turn on 7m away & watch for a big bang or fizz noise
- CMcDougall
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Re: turning on CGA / EGA / VGA '87 monitors?
are these any good??
https://www.ebay.co.uk/itm/Arcade-Game- ... %7Ciid%3A1 would save a lot of space!!
sure I have a VGA converter box to HDMI, up the loft, so could have these to normal new TV....
https://www.ebay.co.uk/itm/Arcade-Game- ... %7Ciid%3A1 would save a lot of space!!
sure I have a VGA converter box to HDMI, up the loft, so could have these to normal new TV....
Re: turning on CGA / EGA / VGA '87 monitors?
RGBtoHDMI supports CGA EGA and MDA from PCCMcDougall wrote: ↑Mon May 11, 2020 9:45 pm sure I have a VGA converter box to HDMI, up the loft, so could have these to normal new TV....
See thread & wiki:
viewtopic.php?f=3&t=14430
https://github.com/hoglet67/RGBtoHDMI/wiki
The gallery here has some sample screencaps from CGA and EGA:
https://github.com/hoglet67/RGBtoHDMI/w ... Screencaps
- 1024MAK
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Re: turning on CGA / EGA / VGA '87 monitors?
I show the series filament light bulb method in this post. The lamp will limit the current if there is a fault. If there is no fault, and the current is low, the filament will not get hot and it’s resistance will be low, so the PSU, TV or monitor under test should work (although no guarantees if it’s a power hungry model).roland wrote: ↑Mon May 11, 2020 7:21 pm For old equipment like radios and televisions with valves we normally "start them up" with a 75W light bulb in series. That way, if there is a huge short circuit then the power will be dissipated by the light bulb and not by the equipment under test. Of course, the monitor might not function properly in this setup.
But before that you should do a visual check of the components, especially capacitors and check with a multimeter if there is no short circuit.
Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki - for answers to many questions...
Fault finding index • Acorn BBC Model B minimal configuration • Logic Levels for 5V TTL Systems
BeebWiki - for answers to many questions...
Fault finding index • Acorn BBC Model B minimal configuration • Logic Levels for 5V TTL Systems
- 1024MAK
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Re: turning on CGA / EGA / VGA '87 monitors?
There have been a number of discussions about the ‘Arcade Game RGB/CGA/EGA/YUV to VGA HD Video Converter Boards’. For example, talk about the GBS8200 starts here.
They convert 15625Hz RGB signals to VGA signals.
Mark
They convert 15625Hz RGB signals to VGA signals.
Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki - for answers to many questions...
Fault finding index • Acorn BBC Model B minimal configuration • Logic Levels for 5V TTL Systems
BeebWiki - for answers to many questions...
Fault finding index • Acorn BBC Model B minimal configuration • Logic Levels for 5V TTL Systems
- CMcDougall
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Re: turning on CGA / EGA / VGA '87 monitors?
read a bit more other week, & bought a arcade board for £3.26 in P&P , so need to wait a month for its delivery
used the Composite out old 8088 big card machine yesterday, & this old 1982 10mb hard drive still works Video of 'noise' from this 10mb model 4020 )1983)
https://youtu.be/FXp46Ph5TGw
used the Composite out old 8088 big card machine yesterday, & this old 1982 10mb hard drive still works Video of 'noise' from this 10mb model 4020 )1983)
https://youtu.be/FXp46Ph5TGw