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Okay, I see I have to get more new stuff out for you!

Just to tell you what's up here: I had my trip to visit my brother and his wife.  I was able to overlap my father's visit, so we got an evening together.  I was able to do several reviews and do a little work on my notes.

My notes have been taking a lot of my writing time.  I have dozens of small notepad notes not trasferred to rolodex-cut cards, and probably over 500 of those cards to file and organize.  Some things, like plot bits, will more or less organize themselves.  Others will be harder.

And I've not been getting that much writing time.  That little electronics project--the regulated 12V charger--has grown tentacles.  The plug is too short to fit the socket extender where it needs to go, so I need a different plug.  The LDO regulator doesn't shut off well enough on low voltage, so I need to put that in, and I decided that for safety I want the cutoff devices to break the hot side rather than the ground.

The interrupting devices are power mosfets.  Unfortunately, the positive-side ones (P-channel) that I have in stock have a very limited gate voltage--8 volts.  (NDP6020).  The max drain-source voltage is a bit low, too, so I may end up finding new ones for future work.  For the present, I can use high-resistance voltage dividers on the input, wasting a few (tens of) microamps for them.

But I need undervoltage detection.  I let myself tinker on paper with a couple of circuit topologies derived from the Schmidt trigger, but I put them aside.  I'll play with them another time.  (Among other things, they require two transistors and seven or eight resistors.  That would be a VERY cramped board.)  So I turned to a pair of similar ICs, one by ON Semi (previously Motorola) and one by Seiko.  The Seiko device operates on a tenth or less the current of the ON Semi device, but the ON Semi device has more complete documentation.

Either way I need a voltage divider, which will waste some current.  The Seiko device would waste less, but I can use the ON Semi documentation to reduce that waste, including an approximation of the device's internal behavior in the circuit theory model of the divider.  That, unfortunately, yields a messy quadratic, but I found, after a few hours of sleep, that I can simplify it greatly.  It's still a pain, but it should only cost me an hour or two to get all the terms into their proper places.

These monitor circuits have the wrong polarity for the need (ground the output when the voltage is too low) so I'll need another transistor to invert the output.  An N-channel low-power mosfet will do.  Ironically, the one I stock is the TN0620.  The output will require another voltage divider to the NDP6020's gate.

Sigh.  Such a simple little thing.  The circuit board will be VERY busy, but it will be a very solid design--up to 20 volts.  I'll also replace the input side tantalum capacitor with a 25 volt job.  (I ordered a variety when I ordered the voltage monitors.)

That stuff will be in in a day or so.  Right now I'll finish the algebra and select the resistor values, and finish up the modified perfboard layout.

Later today I have to take my car to the dealer.  The check-engine light is on.  I fear that a gas station attendent has reuined another charcoal cannister.  If that, I'd let it go except that it will mask other trouble indications.  And, of course, it might be something else.

I have to find out what Best Buy/Geek Squad will charge to swap in a new hard disk on my flaptop, transferring all the content to the new one--if I buy the new disk from them, and if I don't.  (I'd like to go to a 1TB drive, but I'll only buy drives with 5-year manufacturer's warranties, which mostly means WD Black.  BB only offers a 750GB drive, but Newegg has a 1TB WD Black at a very decent price.)

And I will reduce the backlog of notes.  (I produced about seven more last night.)

And that is why Paddy has been away from work.

Highbrow

Does she wear the Pantheist's boots?  If so, perhaps I should rest my case?

Coal train.

I did share a particular opinion: That part of the masculine/feminine divide is a difference in how men and women manage their personal boundaries.  You dismissed it, without counter-argument, without exploration, without asking what in thunder I meant by it.

Which you selfishly keep to yourselves, while we males are forced to share

You're lumping me in with Aristotle?  Now I know I don't merit that!

I don't recall that part, though, and I'm split on it.  Since humor about others means that one is judging them, or at least evaluating them, one can argue for the sense of superiority.  But does it mean a permanent sense of superiority, or just a moment of privilege for being able to apply that judgement?  And what happens when one laughs at oneself?  Really laughs, as in "If you want to make God laugh, tell Him your plans?"

And how does that relate to puns?  When one winces at a pun, what does one feel superior to--or inferior to?

Incorrigible Punster.  Do Not Incorrige.

Does Nash celebrate our superiority to the hamster?  Or is there something deeper and more subtle at work?

I'd make it two.  You have his internal thoughts.  Then you have an action and Apollo's reaction.  I'd group the latter two together.

Thanks, Sol.

It's like one of those things you know you want to get around to fixing one of these days ...

Orphans?