



 This is the MC6847  character generator.  If you look to the right side of the breadboard you can see the amps/transistors to generate the correct output signal (which I left on the breadboard for my own reference before soldering)  The circuit frequency is generated with a 4 pin crystal oscillator, running at the industry standard 3.58 MHz frequency.
This is the MC6847  character generator.  If you look to the right side of the breadboard you can see the amps/transistors to generate the correct output signal (which I left on the breadboard for my own reference before soldering)  The circuit frequency is generated with a 4 pin crystal oscillator, running at the industry standard 3.58 MHz frequency.Below the breadboard is the soldered version of the amp/transistor signal generator. You can see the RCA jack that is plugged into a NTSC LCD monitor. That was the first time I have ever created my own soldered board, and it worked the first time! Sloppy, but it works! This circuit also works with a composite monitor -- in my case, an old Commodore 64 monitor.
This circuit will generate Black and White only, but I am planning on adding an MC1372 so color can be generated. Although I slightly modified the amp circuit by using 2N4400 amps instead of the 2N2222, the design is by Joseph Norman. Thanks Joseph!
 
 
I am using your circuit to test my MC6847. It works fine. The only problem I have is the signal amplifier because I don't have 2N2222 (I just ordered them).
ReplyDeleteThank you for this work!
You can also use the 2N4400 which is what I used. http://www.fairchildsemi.com/ds/2N/2N4400.pdf
ReplyDelete