>> > but it was never a popular as the LM3900.
>>
>> This is what, a 30 year old chip?

I'm sure they are still available for about 0.20 each, but it's easy as pie
making a current differencing amp with three transistors(if anyone is old
enough to have heard of them, if not, they have three terminals and make a
poor substitute for vacuum tubes :-)

Cheers,

Bob

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