Jesse69
New member
I'm stocking up on replacement chips for my Defender boards, but there is a problem. The Later Series Defender drawing set calls chips 1C & 2C as either a 74LS89 or 74LS189 or 74LS289 chip. But I look at my 3 Defender boards and the 1C & 2C chips are marked SN7489N on them, so they're a 7489 chip...
So what chip do I buy? What do your Defender boards have?
Edit - there's also a problem with the 4s & 5s chips - manual says 74LS74 chip but actual chips on a Defender board are marked 7474N.
So what chip do I buy? What do your Defender boards have?
Edit - there's also a problem with the 4s & 5s chips - manual says 74LS74 chip but actual chips on a Defender board are marked 7474N.
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