But professionally and educationally speaking my timeline is roughly:
1984 -> Casio FX-82
1988 -> Casio FX-4000P
1990 -> TI-81
1993 -> HP 48G (this disappeared some time around 2003)
2003 to 2017 -> mostly excel intermission
2017 -> HP 50G / 35S (switch back and forth on and off)
Oh meant to say actually on the calculator front when you mentioned awk. I use dc a lot too. It's nice to be able to mix annotations (comments) and bits of RPN together like that.
This is the really amazing thing: You can now walk into any high street Argos here and buy a fully portable certified Unix machine with perl, dc, awk preinstalled with an excellent terminal emulator and a 64-bit RISC CPU!
Ti 83 ? 86 ?! Hell I though you were older than me not younger !
I was born in 1977, and AFAIR when I was at school the TI range was the TI 81, 82 and 85.
81 was a bit bottom of the barrel to my liking back then... well no honestly I just hated the colour. Much preferred the gray of the 82, so I convinced my mum to fork out 750 Francs for it. Was a huge sum for her, so I was very thankful. Well I think our applied physics teacher did also recommend the 82, to boot.
I loved it, it's well suited / tailored to engineering I find. The 85 was so expensive that only one guy in my class had it. But I didn't like it because it was more suited to pure science and math... the K/B layout was not as practical for engineering I found. some basic functions were not as easy to access I found. Still, I was jealous of his 85... so 25 years later, recently, since they are now dirt cheap, I got one, got my revenge ! About 5 years ago. When I received it, I had a "surprise"... inside the slide cover, there was something written on it in big letters, by hand with I don't know, nail varnish or something similar, but silver looking. Like the conductive varnish to repair heated rear screens on cars.... anyway it read : " BASTARD !!! ". Yes in French it means the same as it does in English !
The seller omitted to inform of this...
So I scrapped the varnish as best I could, but still !
Anyway as I said the 85 is a pain for basic engineering tasks I find, so I would much prefer using my own 82 of back in the day. Problem is that the LCD is kaput, vertical lines all over it
I guess I could try to heat the cable see if that fixes it....
Anyway. Back at school, circa 1995 or 1996, other than that ONE class mate with a 85, there were two other mates that had a one-off as well. One had a Ti 92 ! A monster calculator, more of a portable computer than a calculator. huge screen, mega large K/B, needs to hands to operate it, a monster. Runs on a 68K CPU with 128K of RAM. Way too big and heavy in the bag to be practical, but boy in awe all we were, blown away by this thing !!!!
Then another guy had an HP 48 ! I remember I found it very "expensive". I mean the quality of the material and that of the build./construction, looked much better than the Ti. Also had a lovely comfy velvety pouch to keep it warm ! ISTR I found the quality of LCD better than the Ti. Had a cool Infra red link rather than a wired/cable for the Ti, however since the HP was so expensive he was the only one with a HP so had other calculator to connect to !
I do seem to remember however, that I didn't like the K/B at all ! It was 25 years ago so am not 100% sure, but I think I found the keys hard to press and noisy, compared to my Ti 82. Made typing both uncomfortable and slow. Again, old memories so could be off...
So yeah, at school it was either 82 for most of us, and 85 / HP 48 or Ti 92 for the more wealthy of us.
Slightly older than you but not much
To note, most of the calculators I have owned were well past the date they were introduced. This was because of a passing interest in collecting the infernal things. At one point I had 54 different calculators.
Also I used to buy and sell TI calculators here in medium quantities (tens of them at a time). There was a little niche where broke students where bouncing them for beer money at the end of the school or university year and then paying an absolute fortune for them just before it started because the entire supply was rinsed. I would at average buy for £7 and sell for £40. Do this 100 times and it's a good summer earner. This was a 6 week process of having stacks of mostly TI-83's on my desk, cleaning them up and refurbing them and testing them.
On the TI graphing line I have owned a TI-81, TI-82, more TI-83's than I can count, TI-85, TI-86, TI-89, TI-89 titanium, TI-92, Voyage 200, nSpire CAS.
But professionally and educationally speaking my timeline is roughly:
1984 -> Casio FX-82
1988 -> Casio FX-4000P
1990 -> TI-81
1993 -> HP 48G (this disappeared some time around 2003)
2003 to 2017 -> mostly excel intermission
2017 -> HP 50G / 35S (switch back and forth on and off)
The HP 35S is the nice sweet spot calculator now. It's programmable enough and I don't have to refer to the manual every bloody time I want to remember how to do something like the 50G
As for the TI-92, I did indeed own one for a bit. Very nice machine but quite frankly it's still a TI-89 in a big box. That's not all bad but difficult to rationalise at the time and now. One of my university lecturers had one which was plugged into the large projector adapter which was quite fun to watch.
I actually wrote my first piece of commercial software on the TI-81. This was a horse racing gambling game which sold for 50p a copy and was typed in by hand from memory. If you paid me £2 extra you could get a set of PRNG seeds which guaranteed winners ... I had a real problem with software licensing when someone got a TI-82 and link cable
Fridge Timer update
OK so I looked i my old book that lists all the TTL chips.... the only 8 bit counter is the 373 but I do'nt have one. So I need to cascade no less than x4 4 bit counters instead. Have many of those. So I lined for of those onto the bread board, started to wire them up then..... oh no, Eureka moment ! Btu a BAD one ! Eventuzally realized my big mistake... the 555 gives me my variable duty cycle, cool but .. if I then feed that to a counter chain, the counters will annihilate the duty cycle and force it back to a fixed 50/50 !!
It 's tough to look that stupid publicly but hey... I am just human.
BUT.. there is good news ! Yes.... while I was searching in my drawer full of TTL chips, I found a bin with 3 or 4 different CMOS 4000 chips, odd, what the hell are they doing there.... and among them are a bin with 4060 chips in it !!!!
So I can do as Zoli said, use that as a single chip solution to both generate the clock and long divide it. Then at the output of the dividing chain, I need to implement the variable duty cycle feature one way or another. Zoli mentioned something about that IIRC, with a couple more 4000 chips, will scroil back and re-read him....
But it' 1AM here and I am tired, so going to bed and I will work on that tomorrow.
That is a perfect representation of the Raspberry Poo. It's not a computer; it's a bad idea which is really badly implemented wrapped in a layer of marketing under tight control by a rabid fanbase and moderation on their official forums. Eben and Liz can literally fuck right off. Putting FreeBSD on it is a folly at best when there are real, proper, non shite computers out there you could throw your efforts at. Even that cranky ass 12 year old spooge coated shitbox you got from a house clearance for nothing because the guy who was clearing it out didn't want to touch it incase he got Herpes is a better computer. It's also 100x less likely to fuck up on you even if it's limping along like a rabid squirrel and you have to scrape the jelly like layer of nicotine off it.
So you mean they aren't bad ones, I can just buy the first random generic nu branded super cheap one on Ebay or XYZ, and it will be just fine ?
3 bucks at that ?!
Well OK will buy one real soon then !
The MX54C can use either a PT100 or PT1000 thermocouple, if I believe the documentation I have, below.PT100 & PT1000 sensors are thermistors; they are also similarly standardized as a type K thermocouple. Both are available for $2-8 shipped on fleaBay; the PT100s are more sensitive to EMI, so usually have shorter shielded leads and may have the shield pulled out to a separate pigtail. These are most often used in industrial applications, so will usually be either unterminated or terminated in fork-type screw terminals. You'll have to make up some banana ends on them.
I must be losing it... more than usual... I've looked that pdf over 3 times, and I can't see where it says anything about using the PT100/1000 sensors.
mnem
*toddles off to nuke a power controller*
PT100 & PT1000 (the number refers to the resistance in ohms of the sensor at 0˚C) are metallic resistance thermometers, not thermistors, which are semiconductors. Being low impedance, they are not particularly susceptible to EMI but you do have to take precautions against the effects of lead resistance. PT100s are normally supplied with 4-wire Kelvin (naturally) connections. These are often shielded, but not always.
The resistance of a platinum thermometer increases about 0.4% for each ˚C, so a high-resolution, 4-wire resistance measurement is all you need. Plus some maths, as the response curve is non-linear. There are two parts to the error: the shape of the response curve, which depends only on the purity & heat treatment of the platinum wire; and the deviation from nominal resistance at 0˚C, which depends on the accuracy & repeatability of manufacture. The specification for these sensors appears in IEC 60751
Generally speaking, better accuracy means higher cost. You can start at a few pounds for a IEC 60751 class C thermometer, going up to thousands for an individually-calibrated probe with an accuracy in the 10's of mK level over a wide temperature range. That's without venturing into the realms of metrology-grade SPRTs...
And also missing from Vince's lab: a simple, commercial day or week timer switch.
Borrow the one from your meter or microwave oven or meat thermometer.
mnem
What "meter" ? No not going to dismantle my poor u-wave oven !!
No meat thermometer here either.
I want to design this thing, the time pressure / emergency makes it even more fun...So... you don't have a proper bench thermometer, or even a "K" thermocouple as used on almost every DMM since the dawn of time...?
What. The. Actual. Fuck.
Seriously, this is an egregious shortcoming we shall have to pick on you for... at least the next 5 minutes.
If you go dismantle that cheap digital thermometer you have on the wall right now we'll forgive you... for now.
mnem
pssst... on most microwaves that have a thermometer, it plugs in. Easy-peasy to borrow.
A whole new world of Kelvin-nuttery awaits! There is nothing to beat the satisfaction of making up an ice point in a 1 litre vacuum flask (using shredded ice from de-ionized water, naturally, for best accuracy), immersing the lab reference PRT probe, and having it read a stable 0.00˚C for hours. My second-best PRT probe read -0.02˚C. A random K-type thermocouple probe read +1.2˚C, which is about average for a K-type. T-types are rather better, usually about ±0.5˚C, but not guaranteed.
Thermistors are generally quite stable, but the response curves vary quite widely and are often mismatched with the curve assumed by the meter. With individual calibration they can give excellent results, within ±0.1˚C.
Will probably get the children "hp" 35s calcs when they need something for school. Just to fuck with teacher brains.
What, you don't have an HP Quartz thermometer?
Will probably get the children "hp" 35s calcs when they need something for school. Just to fuck with teacher brains.
Unlikely to work: they'll probably specify the calculator. That will be to get the correct answer to 1+2*3 (q.v.)
Your eyes are not deceiving you. There are 3 of them. 2 fully functional and 1 still needs some work. Ever since college 51 years ago I've wanted a Type 547. In the past year or so the TE gods have seen fit to bless me with 3 of them. I'll describe the story of each in detail.
Amazing work as always. Another great read.
I'm glad there's some TE content in here still
Getting hankering for HP and Tek kit now
Will probably get the children "hp" 35s calcs when they need something for school. Just to fuck with teacher brains.
Unlikely to work: they'll probably specify the calculator. That will be to get the correct answer to 1+2*3 (q.v.)
They'll be more likely to specify lack of programs / insist that programs be cleared before tests. [hp] (actual [hp] calcs, not the Chinesium builds like the current 35s) were always grudgingly accepted back in the day.
So yeah, at school it was either 82 for most of us, and 85 / HP 48 or Ti 92 for the more wealthy of us.
Borrow the one from your meter or microwave oven or meat thermometer.
mnem
What "meter" ? No not going to dismantle my poor u-wave oven !!
No meat thermometer here either.
I want to design this thing, the time pressure / emergency makes it even more fun...So... you don't have a proper bench thermometer, or even a "K" thermocouple as used on almost every DMM since the dawn of time...?
What. The. Actual. Fuck.
Seriously, this is an egregious shortcoming we shall have to pick on you for... at least the next 5 minutes.
If you go dismantle that cheap digital thermometer you have on the wall right now we'll forgive you... for now.
mnem
pssst... on most microwaves that have a thermometer, it plugs in. Easy-peasy to borrow.
A whole new world of Kelvin-nuttery awaits! There is nothing to beat the satisfaction of making up an ice point in a 1 litre vacuum flask (using shredded ice from de-ionized water, naturally, for best accuracy), immersing the lab reference PRT probe, and having it read a stable 0.00˚C for hours. My second-best PRT probe read -0.02˚C. A random K-type thermocouple probe read +1.2˚C, which is about average for a K-type. T-types are rather better, usually about ±0.5˚C, but not guaranteed.
Thermistors are generally quite stable, but the response curves vary quite widely and are often mismatched with the curve assumed by the meter. With individual calibration they can give excellent results, within ±0.1˚C.
What, you don't have an HP Quartz thermometer?
Borrow the one from your meter or microwave oven or meat thermometer.
mnem
What "meter" ? No not going to dismantle my poor u-wave oven !!
No meat thermometer here either.
I want to design this thing, the time pressure / emergency makes it even more fun...So... you don't have a proper bench thermometer, or even a "K" thermocouple as used on almost every DMM since the dawn of time...?
What. The. Actual. Fuck.
Seriously, this is an egregious shortcoming we shall have to pick on you for... at least the next 5 minutes.
If you go dismantle that cheap digital thermometer you have on the wall right now we'll forgive you... for now.
mnem
pssst... on most microwaves that have a thermometer, it plugs in. Easy-peasy to borrow.
A whole new world of Kelvin-nuttery awaits! There is nothing to beat the satisfaction of making up an ice point in a 1 litre vacuum flask (using shredded ice from de-ionized water, naturally, for best accuracy), immersing the lab reference PRT probe, and having it read a stable 0.00˚C for hours. My second-best PRT probe read -0.02˚C. A random K-type thermocouple probe read +1.2˚C, which is about average for a K-type. T-types are rather better, usually about ±0.5˚C, but not guaranteed.
Thermistors are generally quite stable, but the response curves vary quite widely and are often mismatched with the curve assumed by the meter. With individual calibration they can give excellent results, within ±0.1˚C.
What, you don't have an HP Quartz thermometer?
So yeah, at school it was either 82 for most of us, and 85 / HP 48 or Ti 92 for the more wealthy of us.
One used at school, one used at work, one because I lusted after it at university (it was bolted to the desk in the main library!), and one duplicate in case the other failed.
All either significant innovations or rare.
All working.
And also missing from Vince's lab: a simple, commercial day or week timer switch.
I have multiples of these, perhaps I should send him one, in the spirit of Entente Cordiale.
Borrow the one from your meter or microwave oven or meat thermometer.
mnem
What "meter" ? No not going to dismantle my poor u-wave oven !!
No meat thermometer here either.
I want to design this thing, the time pressure / emergency makes it even more fun...So... you don't have a proper bench thermometer, or even a "K" thermocouple as used on almost every DMM since the dawn of time...?
What. The. Actual. Fuck.
Seriously, this is an egregious shortcoming we shall have to pick on you for... at least the next 5 minutes.
If you go dismantle that cheap digital thermometer you have on the wall right now we'll forgive you... for now.
mnem
pssst... on most microwaves that have a thermometer, it plugs in. Easy-peasy to borrow.
A whole new world of Kelvin-nuttery awaits! There is nothing to beat the satisfaction of making up an ice point in a 1 litre vacuum flask (using shredded ice from de-ionized water, naturally, for best accuracy), immersing the lab reference PRT probe, and having it read a stable 0.00˚C for hours. My second-best PRT probe read -0.02˚C. A random K-type thermocouple probe read +1.2˚C, which is about average for a K-type. T-types are rather better, usually about ±0.5˚C, but not guaranteed.
Thermistors are generally quite stable, but the response curves vary quite widely and are often mismatched with the curve assumed by the meter. With individual calibration they can give excellent results, within ±0.1˚C.
What, you don't have an HP Quartz thermometer?
Vince, ignore the Kelvin Heads. I'm sorely lacking in temperature measurement too. I have the 2465 DMS with temp measurement capability with a home made probe but it reads about 4F high.
But what would I do with such a thing, in the lab ? Use case example please ?!
Fridge Timer update
OK so I looked i my old book that lists all the TTL chips.... the only 8 bit counter is the 373 but I do'nt have one. So I need to cascade no less than x4 4 bit counters instead. Have many of those. So I lined for of those onto the bread board, started to wire them up then..... oh no, Eureka moment ! Btu a BAD one ! Eventuzally realized my big mistake... the 555 gives me my variable duty cycle, cool but .. if I then feed that to a counter chain, the counters will annihilate the duty cycle and force it back to a fixed 50/50 !!
It 's tough to look that stupid publicly but hey... I am just human.
BUT.. there is good news ! Yes.... while I was searching in my drawer full of TTL chips, I found a bin with 3 or 4 different CMOS 4000 chips, odd, what the hell are they doing there.... and among them are a bin with 4060 chips in it !!!!
So I can do as Zoli said, use that as a single chip solution to both generate the clock and long divide it. Then at the output of the dividing chain, I need to implement the variable duty cycle feature one way or another. Zoli mentioned something about that IIRC, with a couple more 4000 chips, will scroil back and re-read him....
But it' 1AM here and I am tired, so going to bed and I will work on that tomorrow.Here's the solution with 4060+4001: make the 4060 to count to the desired time interval(1h, that's around 4.5Hz oscillator frequency). Connect 4001(1(A),2(B)) to 4060(2(Q13),3(Q14)), and all the other 4001 inputs(C,D,E,F,G,H) to the ground; add power-on reset to the 4060(RC; 10kΩ+10nF).
On the start-up: pin3(J) of the 4001 stays up for 15 minutes, and down for 45 minutes; after that the cycle repeats itself.
Enjoy!
P.S: this timing is doable with the CMOS(7555) 555
Edit: I've made a schematic, since an image worth a thousand words.