Re: Ortonview PCB
I found some SMD 220pF capacitors, so I soldered one in place in the buffer enable delay mod and brought the board home. I decided to try it straight off, with buffers and extra RAM fitted. Unfortunately it doesn't look good on first try, there is a lot of noise on the displays between the address and data fields and the VDU itself is producing an abormal - height screen.
So I removed the PIC and the buffers leaving only the 6116 and 7402 address decoder in place, powered up to find a normal MK14 display and found that the memory by itself works fine, with any data entered over the range 0200-07FF 'sticking' as it should.
Next, I'll try powering the fully populated OrtonView from 5V-only - in those circumstances it should just display the random start-up content of the 6116 but should otherwise give me a normal 16 x 32 character VDU display output.
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