LGR - Unboxing a New 1980s Amdek Monochrome Monitor
video description
Date: 2022-04-14
Related videos
Comments and reviews: 9
John
The reason you are not seeing the ghosting/persistence is the phosphor being used. Most monochrome monitors used a phosphor that didn't have a code (Amber, P31 (Green, or P4 (B&W TV) phosphor. IBM, recognizing that the low refresh rate of MDA (50Hz) would present an eyestrain issue and instead used a longer persistence P35 phosphor.
Strangely, my monochrome experience differs because I grew up going to schools using Apple II computers in which a monochrome monitor uses the same analog video signal meaning that the same exact graphics are transmitted to the monitor without the color blending that occurs in composite monitors. Strangely enough, these exact monitors (either the genuine Apple or the third party like my Zenith) can be connected to IBM CGA cards for monochrome graphics.
reply
The reason you are not seeing the ghosting/persistence is the phosphor being used. Most monochrome monitors used a phosphor that didn't have a code (Amber, P31 (Green, or P4 (B&W TV) phosphor. IBM, recognizing that the low refresh rate of MDA (50Hz) would present an eyestrain issue and instead used a longer persistence P35 phosphor.
Strangely, my monochrome experience differs because I grew up going to schools using Apple II computers in which a monochrome monitor uses the same analog video signal meaning that the same exact graphics are transmitted to the monitor without the color blending that occurs in composite monitors. Strangely enough, these exact monitors (either the genuine Apple or the third party like my Zenith) can be connected to IBM CGA cards for monochrome graphics.
reply
catsspat
From quick search, it appears that Hercules graphics mode ran 1 bit per pixel at 720x350 resolution, with 50. 32Hz refresh rate, although I'm not sure if there is any interlacing involved. That's about 1. 5 MB/s. Comparatively, UHD 144Hz monitor running at 30 bits per pixel (10 bits x 3) without any compression is about 4, 271. 5 MB/s, a little over 2800 times more information.
reply
From quick search, it appears that Hercules graphics mode ran 1 bit per pixel at 720x350 resolution, with 50. 32Hz refresh rate, although I'm not sure if there is any interlacing involved. That's about 1. 5 MB/s. Comparatively, UHD 144Hz monitor running at 30 bits per pixel (10 bits x 3) without any compression is about 4, 271. 5 MB/s, a little over 2800 times more information.
reply
horus
-New cables. smells like. rubbery plastic stuff! - ROFL! Well played, Clint. Well played.
I used to have an old Actrix DS portable. The amber monitor built in to it was only 7-, 80 X 25, but was bearable because it was a very sharp amber display. I think it might even have been an Amdek product. (I really wish I'd kept that machine now)
reply
-New cables. smells like. rubbery plastic stuff! - ROFL! Well played, Clint. Well played.
I used to have an old Actrix DS portable. The amber monitor built in to it was only 7-, 80 X 25, but was bearable because it was a very sharp amber display. I think it might even have been an Amdek product. (I really wish I'd kept that machine now)
reply
phalanger1
Amber monitors were so pretty. I had a Hercules one. It sucked for graphics but was absolutely fantastic for text. Such a flicker-free, relatively high-res display that was very easy on the eyes and a pleasure to look at. But ofcourse I still gamed more on it than anything else, being like 12
reply
Amber monitors were so pretty. I had a Hercules one. It sucked for graphics but was absolutely fantastic for text. Such a flicker-free, relatively high-res display that was very easy on the eyes and a pleasure to look at. But ofcourse I still gamed more on it than anything else, being like 12
reply
Dane
I always find it fascinating when NOS -this- old manages to survive especially when the manufacturer goes under. Someone bothered to care for and leave untouched warehouses full of electronics for decades under multiple owners. Makes you wonder why they didn't just sell or scrap them.
reply
I always find it fascinating when NOS -this- old manages to survive especially when the manufacturer goes under. Someone bothered to care for and leave untouched warehouses full of electronics for decades under multiple owners. Makes you wonder why they didn't just sell or scrap them.
reply
Darrel
Bought this instead of the small green monochrome Apple monitor for our Apple IIc. The amber non-reflective screen was highly rated for safety in Sweden. Unfortunately I did not know that the Apple displayed less (512 vs 640. The unit and amber looked professional.
reply
Bought this instead of the small green monochrome Apple monitor for our Apple IIc. The amber non-reflective screen was highly rated for safety in Sweden. Unfortunately I did not know that the Apple displayed less (512 vs 640. The unit and amber looked professional.
reply
Cory
-LGR: A continual excuse to whip out IBM computers and do stuff that is objectively underwhelming, but subjectively amazing-
Beautiful. From those of us who also crave these unsung tech sagas: Thank you for everything that you do. We appreciate it very much!
reply
-LGR: A continual excuse to whip out IBM computers and do stuff that is objectively underwhelming, but subjectively amazing-
Beautiful. From those of us who also crave these unsung tech sagas: Thank you for everything that you do. We appreciate it very much!
reply
DoctorX17
Mmmm, amber. I love amber displays. I tend to make my Windows Command Prompt amber.
Do you think the fact that this thing was in the box and unused has anything do with the lack of ghosting? Would a used display look so clean and smooth?
reply
Mmmm, amber. I love amber displays. I tend to make my Windows Command Prompt amber.
Do you think the fact that this thing was in the box and unused has anything do with the lack of ghosting? Would a used display look so clean and smooth?
reply
Peter
11: 30 I used to play games using such a screen as featured here back in 1987. I still play games and it blows my mind just how much graphics and sound (you should install an Adlib or something in that old pc) have advanced in over 30 years.
reply
11: 30 I used to play games using such a screen as featured here back in 1987. I still play games and it blows my mind just how much graphics and sound (you should install an Adlib or something in that old pc) have advanced in over 30 years.
reply
Add a review, comment
Other channel videos
