WTB: 4723B (dual 4-bit latch) and 1.782 Mhz crystal (HC-33 pkg) for ALF MC-16 replica

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WTB: 4723B (dual 4-bit latch) and 1.782 Mhz crystal (HC-33 pkg) for ALF MC-16 replica

Working on a replica of the ALF Products MC-16 card.

This is the original 1978 card, not the newer one with the programmable sound generator chip.

I'm having trouble finding a 1.782 Mhz crystal that drives the 8253 timer chip.

I could use a higher-frequency crystal, but would prefer not to.

The closest I've found so far is a 10.692 Mhz crystal from a surplus radio dealer (it's 6x the original frequency)

I could substitute something for the 4723 as long as it was functionally equivalent.

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Re: WTB: 4723B (dual 4-bit latch) and 1.782 Mhz crystal ...
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Re: WTB: 4723B (dual 4-bit latch) and 1.782 Mhz crystal ...

The 4723 can be replaced by a 74LS256. The 1782kHz quartz can be replaced by a clock-halved 3560kHz Quartz (2 flip-flops). The DAC can be replaced by a AM6070.

If you want to make some Boards ... i could use 6 or 7 bare PCB

Songs played with the MC1 ... not the same as the MC16, but nice too Wink

-Jonas

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