Replacement for a DEC 7474 Chip

Chris Zach cz at
Sun May 15 02:42:06 CDT 2022

I'll have to check when I get back from Norway but I believe I replaced thirty or so flip flops with 74ls74 chips with no problems. This was on my pdp8l and granted Dec used a lot of 4 and 8 input nand gates to drive loads 

On May 15, 2022 12:08:55 AM GMT+02:00, ben via cctalk <cctalk at> wrote:
>On 2022-05-14 11:50 a.m., Nigel Johnson Ham via cctalk wrote:
>> AFAIR LS can only drive one unit TTL load.
>>>     paul
>LS is 4 TTL, 4 ma low.
>Was there a trick of forcing the output of D flip flip
>to clear it? I was wondering if this is what kills all
>the 7474's?

Sent from my Android device with K-9 Mail. Please excuse my brevity.

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