When I added a video input to a 12" B&W TV to use with my Apple ][+ clone, I used an LM318 as a buffer. It was a huge improvement over using an RF modulator.
Your RF modulator limited the bandwidth to around 4 MHz while your opamp approached 10 MHz His transcoder really needs to get north of 20 MHz and would be noticeable even limited to 30 MHz.
G²
The 741 reminds me of a silly mistake I made as a junior engineer.
My boss asked for a TV video signal buffer to be added to some equipment.
So I merrily went off and picked up a 741 and tried that.
It gave a lovely black and white picture !
Of course colour info is 4.433MHZ and the 741 filtered that out nicely.
Another lesson to add to the many I had over the years.
Probably far short of 4 MHz since the Apple clone was putting out composite video with the NTSC carrier thing at 3.58 MHz.
About a year ago, a UK electronics magazine published plans for an RGB/YUV converter; probably Elektor. The US edition left that article out. A converter like that may allow a modern TV with YUV inputs to display the RGB output from a vintage computer (Amiga, Atari ST, Apple II with RGB card) or arcade game.
About a year ago, a UK electronics magazine published plans for an RGB/YUV converter; probably Elektor. The US edition left that article out. A converter like that may allow a modern TV with YUV inputs to display the RGB output from a vintage computer (Amiga, Atari ST, Apple II with RGB card) or arcade game.
Its an A500, with 1 meg chip ram.
Mega Midget Racer accelerator at 36Mhz, FPU at 50Mhz.
A590 SCSI controller, with 1 meg "fast" ram
And 512k of super fast ram on the mega midget racer.
2gig scsi HDD, plus an external scsi CD rom 😉
It needs more slow ram, I had an 8meg ram expansion that went between the 68000 cpu, and accelerator, but realised it was causing massive issues when trying to copy from the CD Rom to the HDD 🙁
Mega Midget Racer accelerator at 36Mhz, FPU at 50Mhz.
A590 SCSI controller, with 1 meg "fast" ram
And 512k of super fast ram on the mega midget racer.
2gig scsi HDD, plus an external scsi CD rom 😉
It needs more slow ram, I had an 8meg ram expansion that went between the 68000 cpu, and accelerator, but realised it was causing massive issues when trying to copy from the CD Rom to the HDD 🙁
lol i love the comments that sysinfo put in, "smell the rubber?"
nice performance you've got there.
http://www.amiga-hardware.com/showhardware.cgi?HARDID=64
Whats the part numbers of those ram chips? Maybe someone can pipe in and help out, or do you need a standard expansion port 1 meg card, plenty of those on ebay.
nice performance you've got there.
http://www.amiga-hardware.com/showhardware.cgi?HARDID=64
Whats the part numbers of those ram chips? Maybe someone can pipe in and help out, or do you need a standard expansion port 1 meg card, plenty of those on ebay.
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The Mega Midget Racer has an optional 2 or 8meg expansion BOARD that plugs in to the side.
Mine has 512k on the main MMR board, but no extra fast ram on the accelerator.
I have 512k in the trapdoor, with the motherboard modified to access this as chip ram 😉
Mine has 512k on the main MMR board, but no extra fast ram on the accelerator.
I have 512k in the trapdoor, with the motherboard modified to access this as chip ram 😉
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