I will keep that in mind when selecting the "pimping" resistor-- what do you think, about 75K?
75k gives 12.5k or 50°C, that's too low, I think, especially in your nice, hot place.
I have chosen 100k (precision wire wound) for 65°C.
I didn't want to get off-topic, (but you opened the door):
I am not too much worried about the CO2, since that is a big hoax that was promulgated by Al Gore and his scientist buddies at NOAA, NASA, and the East Anglia University in England. Haven't you seen the "ClimateGate scandal" about the emails threatening scientists to "tow the line" on this? How about the "hacked" computer model that "proves" humans are causing global climate change? (All of this is available for download on Wikileaks and Bit-Torrent if you care to look). Did you know Al Gore has set up a "CO2 credit" trading company, and he stands to make billions of dollars from this? I wanted to know what was really going on, so I traveled to the National Center for Atmospheric Research [NCAR] in Boulder Colorado. This is the place where everyone in the world sends there weather data. The data is crunched by super computers in the basement (which I saw), and these make world-wide weather predictions. These scientists are to the left of Chairman Mao-- and so they have a strong political incentive to back the "official story" (of anthropomorphic climate change)-- but, to their credit, they refuse to whore themselves (and their scientific reputations), and so they tell the truth-- humans are causing somewhere between 2% and 5% of the total climate change-- the rest is caused by natural geologic changes and (mostly) changes in the heat output of the sun.
Well, I'm also very skeptical, as I think those meteorologists do not use strictly scientific methods.
They capture very small effects, and comparing the big time scale where natural climate changes happen (several 10k years) to the very small time scale where data were collected precisely (<50years), I feel that the statistical basis and the evidence of their arguments are not correct.
Meanwhile, it turns out that they did not take every possible other effects into account to prove root cause by mankind, but perhaps only those, which fit in their picture and in their theory.
Especially this very determinative, often agressive attitude of this meteorological community, compared to those subtle effects makes me doubt the correctness of their thesis.
That's very weird for me, because the scientific community of physicists is much more cautious in this subject.
They also speak of "indication" for a climate change by mankind, but not of "a matter of fact".
It is also usual and absolutely required in physics to make very critical reviews of theories and methods.
And this is what is totally lacking at the meteorologists.. every critical voice has been damned by them.
That's totally un-scientific.
For two totally different reasons, I think that we really should save CO2, anyhow:
- It's a pity to simply burn oil and other fossil material, instead of producing more valuable products out of it, as medicine, plastics, and so on.
If the oil is gone, it will be very hard to find a replacement.
- If we simply exhaust fossil material to produce "energy", without the need to search for any alternative afterwards, this will for sure create wars for the remainders.
I live in Las Vegas Nevada, USA-- the climate here is very hot in the summer, and I am spending about US$500 per month on electricity just to keep the house cool. It is starting to cool down a little bit now, so my power bills are going to go down a bit. So the 30W that the 3458A takes is a "drop in the ocean" compared to the big picture.
OK, then it's really true that Americans use about 10 times more energy than even Europeans..
![Roll Eyes ::)](https://www.eevblog.com/forum/Smileys/default/rolleyes.gif.pagespeed.ce.XcUK202Yqt.gif)
Perhaps only those living in hot areas of the US..
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/xwink.gif.pagespeed.ic.cldandycH0.png)
We pay 1200€ (1500$) per year for electrical energy, 4800kWh/yr, and the price is still rising (>27 EU-Cents / KWh).
My 3458A has an HP badge on the front. It has the newer front panel color that the new Agilent 3458A's have. So it's not one of the first units off the production line, but it has to have been made before the HP instrumentation group became Agilent, which (IIRC) was over a decade ago-- so yes, the reference can be considered to be "well aged".
Should be produced before 2001. Did you check date codes on the components inside?
Which serial number do you have? I.e. the digits behind the 2823A?
Joe Geller collects those numbers to estimate, when a certain serial number has been produced.
He thinks, that the 5 digits are in consecutive order, so about 40k instruments have been built between 1989 and today.
He will be delighted, if you send him the serial number of your HP3458A and an estimate from the date codes.
Frank