Re: Temperature sensing technologies

Am 13.09.25 um 10:51 schrieb Jan Panteltje:

The box of the SR-44 contains two step-up transformers. Touching the secondaries in use is not so funny. You can feel the music!

No, without the characters after the 803. After the relative success of the 800 series they tested how far they could increase prices for "improvements". That got completely out of hand.

Got mine from ebay for a price I could not resist.

I hear everything that I'm not supposed to hear. :-)

Gerhard

Their nonlinearity will emphasize the hottest, in a sort of heavily-weighted average way. That would work fine for a shutdown system where precision isn't a big deal.

NASA likes them for space missions, and we want NASA to like us, so we like them.

It makes a current PTAT, but won't work below -55c, so the first 200K of its output range is useless or worse. That hugely magnifies offset errors and wastes ADC bits.

It's inherently high impedance so needs well-shielded cabling, far from power lines or anything else AC.

It needs multi-megohm insulation too.

And it's crazy expensive.

And sole-source.

These were LM2876T. The first data sheets said a Boucherot network wasn't needed but later revised ones said they may be necessary in some circumstances.

It's a current source. The paralleled output will be the sum of the two absolute temperatures.

Divide by two and get the average.

It's funny that all the examples on the data sheet have trimpots. You have to stick every one in an ice bath and tweak it.

Horrible little part. John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

The best linear parts come from TI and ADI and OnSemi. ST and Infineon and Renesas make some.

Makes no sense. The tariffs are on imports, not exports.

Buy Russian parts.

It's interesting how few linear ICs come from asia.

TI decided, some years ago, to concentrate on analog parts. Smart move.

I need some fast-ish ADCs and DACs for a new product line. Something like 12 bits and 5-10 Ms/s. TI and ADI are the clear winners.

Excellent. More parts for me.

Remind me, who started those wars?

Narcotics kill about 100K Americans per year. It's reasonable to stop the smuggling.

You refer to cutting up young girls?

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

I would expect a platinum RTD or a thermocouple to be a lot less radiation sensitive than a complex low-current linear IC.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Radiation on thermocouple analog readout components creates drift in accuracy over time since the signal is so small electrically. So the AD590 isn't perfect, but they're better than thermocouples over time.

Russia invaded Ukraine. Hamas staged a large scale terrorist attack on Israel. Illegal israeli settlements in Palestine have a long history of small scale terrorist attacks on their Palestinian neighbours, but they never got a lot of publicity.

It would be a lot more reasonable to improve US domestic support for it's poorer citizens. When 100k Americans a year are resorting to self-medication to reduce their misery, something like universal health care would be a whole lot more reasonable, if rather more expensive.

The Jews only make a habit of circumcising males. Some Muslims circumcise females as well.

Given reasoning like that, I'm sure glad you don't design electronics.

Granting that the CIA played a considerable role in instigating the coup that displaced Mossadegh in Iran in 1953, and put the Shah in power for the next 26 years, there's nothing implausible about the hypothesis.

They'd have had to have been mad to do something quite so stupid, but US foreign policy isn't all that rational.

Russia has a long and sad history of cruelty, poverty, and alcoholism. Other slavic countries want to be more european, more "western", more propserous and modern. The Russians still hate "the west."

I had dinner with the US ambassidor to the USSR, in his residence in Moscow.

And I had some extended interaction with some people in the organization you reference.

All those people seemed smart, thoughtful, patriotic, and ethical.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Putin does seem to want to restore the "Russian Empire". I doubt if the conscripts he is getting slaughtered in the Ukraine share his enthusiasm.

Or look that way to you, which isn't all that convincing. Your ideas about what might be smart, thoughtful and ethical don't seem to be all that reliable. You do think that Trump has common sense.