Can you help identify this symbol?

As part of an encoder chip for the keyboard on an Apple II Plus I came across this symbol in the schematic that I can't identify. Any idea what this is?

Thanks

Robert Opalko

Here is where I clipped it from (also note the one on the other side denoted "ØP"??)

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jc2048 over 3 years ago in reply to shabaz +5

Having both a weak pull-up and a stronger one that gets enabled when it's needed (by a clock phase) was probably a way to get the chip power consumption down a bit. I've seen the symbol elsewhere in…
jc2048 over 3 years ago in reply to jc2048 +5

Here's another example of the symbol's use. This is the internal schematic of a Signetics 2501 SRAM from a 1975 datasheet. They've drawn it a bit more like the usual MFET symbol. Intel preferred this…
scottiebabe over 3 years ago +4

Best guess is depletion mode nmos logic, but I'm not 100% certain. Take care

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0 colporteur over 3 years ago

I would go with a variable resistor but I do get some confusion by having a second similar component shown without the wiper connected. 0P means zero potentiometer or a resistor. Guessing mind you.
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0 colporteur over 3 years ago

I would go with a variable resistor but I do get some confusion by having a second similar component shown without the wiper connected. 0P means zero potentiometer or a resistor. Guessing mind you.
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