Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Never heard of that brand... Swiss only ?! 

Wow the LCD looks superb, want one now !

On nooo, do not put the finger in the open wound.

I have a free42 I do not need Swissmicros
I have a free42 I do not need Swissmicros
I have a free42 I do not need Swissmicros.....

There, there, Z... here, have some emulator eyecandy. 

   

mnem
Unspoken TEA Directive #17: "You don't have to need it to have it." 

[Zucca]

I am strong and I resist!

I smell some emu48 there.

What do you get when you do 1 sin cos tan atan acos asin?

I use free42 because it is giving me back 1 at the end....

[mansaxel]

I am strong and I resist!

I smell some emu48 there.

What do you get when you do 1 sin cos tan atan acos asin?

I use free42 because it is giving me back 1 at the end....

My DM42 gives "1.00000000". Is that precise enough?

 

[mnementh]

I get a headache. 

You know I'm math defective... but I'll be brave, just for you, Z.

mnem
No good deed goes unpunished.

[mnementh]

What do you get when you do 1 sin cos tan atan acos asin?

I use free42 because it is giving me back 1 at the end....

EDIT: No joy, Z; 48sx returns: 0.999998113101

*cue unhappy wah-wah-wahhh sound*

I still love my emulators on a modern 10 inch tablet screen with a modern digitizer tho... even with my big ol' Shrek hands, I can hit the right keys without trying.

mnem
 

[mansaxel]

I get a headache. 

You know I'm math defective... but I'll be brave, just for you, Z.

mnem
No good deed goes unpunished.

Oh, and using LibreOffice, one gets back to the start, too:

	1
	0,841470984807896
	0,666366745392881
	0,786357394978223
	0,666366745392881
	0,841470984807896
	1

Perhaps more "computer user" ^W^WDragon friendly?

[mnementh]

meh.   

mnem
 

[mnementh]

That is neither crusty nor agitating, just sick.

Spank youuuu... spank you vurrry muuuuuch!

Ehhh... what you call a Real Computer is, in fact, a Real Computer KIT.

Those who build that kit to completion -- and they are admittingly few -- will be in a unique position to actually understand what is going on.

Those who do not understand, are doomed to reimplement it, poorly. (From Henry Spencer, prominent space, Usenet and UNIX neckbeard.)

*suspender-adjustingly* *beard-scratchingly*

And those who do understand are doomed to forever stand by helpless, as those who do not understand reiterate the same faulty implementation over, and over, and over, and over... 

It's just another flavor of Cassandra's Curse. 

mnem
"...like trying to hold back the tide with a broom."

[Andrew_Debbie]

I am strong and I resist!

I smell some emu48 there.

What do you get when you do 1 sin cos tan atan acos asin?

I use free42 because it is giving me back 1 at the end....

My vintage HP gives 0.99901674

[mnementh]

...Honestly, if all you people with weird alphabets were just going to give up, you could have told us computer folks - do you have any idea how much work it took to get the world where one could reliably type "ü" or "ファックオフラウンドアイ"? [Fx: Goes off pouting, to sulk over all that wasted work]

  BWAHAHAHAHAHA!!!

Thanks for the belly laugh, C.

When I first moved to Tejas, I occasionally heard the word güero (pron. wey-ro) if I ignorantly went into one of the stores that the Mexican locals considered their home turf... I assumed it was derogatory, and mostly meant "You don't belong here".

It wasn't until much later that a friend coworker explained that while the word meant literally "blond" or of Caucasian descent, the connotation was very similar to "gaijin" in the same context: a specific reference to one being not only white and outsider, but less than human as well; a white ghost.

After that, I got in the habit of asking politely that if they were going to cuss at me, please use English so the white boy could understand.

mnem
 

[factory]

Oh wow it's 4H30  almost, eyes are getting tired... need to go to sleep, but I will post this quikc before I go to sleep !

Look what I foudn in a some random box ! I had completely forgotten about this thing ! An old retired engineer friend gave me a ton of stuff 3 years ago, including some TE, but never had the opportunity so far to check out everything he gave me... so here is what I just found !



A HP  3200B VHF oscillator !!! 

Can do 500MHz !   I can do " RF " now  ! 

At least I can check the B/W of my scopes and probes and frequency counters, and play with filters ! Can do a bunch of stuff with this thing ! 

Seems to work just fine all the way to 500MHz. Only thing I see wrong is the amplitude knob. Well the one at the bottom right, that doubles as a power switch... I guess it's the amplitude knob.
However it does not do much ! If I crank it all the way, I get only about 20/25% increase in amplitude compared to its minimum setting !
Will have to investigate that.... service manual is available I guess.... since he gave me printed copy of it... so there is hope.... or not : I cracked it open. all the RF black magic happens behind closed doors, inside a beautiful, huge super heavy die cast alloy enclosure ! No human allowed inside for sure... so I don't know. 

500MHz so... for once, out with the 200MHz combiscope, and in with the TDS 544A (500MHz B/W). A good opportunity to give it some use eh ?
So it looked all kinda nice until about at 400MHz where the sine wave become very unstable, amplitude goes all over the shop, scope can't trigger on it anymore.. even though it should, regardless of the amplitude going hay wire, because signal is clean, plenty of signal amplitude to trigger (on zero crossings here).
Looks weird so I made a short video clip of it to show you, below.

...snip...


30 seconds later.... I hear a fire works inside the 2467B, and 2 seconds later, a big cloud of white smoke comes out the rear of the scope and starts filling the living room !!!     

So looks like it's not just the electrolytics in the PSU that needs replacing... the bloody RIFA just gave up the ghost as well ! 

But that's fine... this scope has proved how exceptional, breathtaking it was technically, so I am mooooore than happy to take it apart and do all the servicing that needs doing to get it back into shape...

So to suim it up.

- I just got a cool HP 3200B 500MHz oscillator that's got a defective attenuator.
- A TDS 544A scope that can't trigger (or other problem ?) above 400MHz... reducing the usefulness of the scope somewhat...
- A TDS 694C that needs a keypad fixing...
- A 2467B that escaped the magic smoke.

The control on the front of the HP 3200B is not the attenuator, it's a vernier control for fine adjustment, you have missed the attenuator as it is hidden as part of the output connector, loosen the knurled nut and the piston attenuator slides out to reduce the output.

Picture above from here; https://sites.google.com/site/rstevescott/home/boatanchor-test-equipment/hp-3200b-vhf-oscillator

I'm after Boonton branded 3200A for my collection, not looked for a while though, more of the 3200A here; http://www.hparchive.com/Boonton/BRC-The-Notebook-37.pdf

Oh and the frequency range switch you said was hard to turn, that is probably due to dried out grease on the various shafts in the mechanism, that operate the switch & turn the scale drum.

2467B update : just gave it a chance... I plugged it back and tried to power it up.... it still works just fine !!!

So the RIFA smoke and fireworks didn't kill it, still works !!!   This scope is a warrior !! 

I guess the RIFA went open circuit rather than shorting, when they released the magic smoke.

Anyway will take it apart soon to fix the PSU. This wonder of a scope deserves a good cleaning and whatever servicing it needs. This thing is not a trouble maker no.. it's an asset in the lab 

The RIFA madness  might not be open circuit, some of them are in series with a resistor, hopefully the board isn't burnt as a result of the resistor burning out, probably best to replace with a fusible/flameproof of the same rating if it's blown too.

David

[Vince]

Oh a contest !! 

My old Mk1 TI 85 gives 1.000,000,053,32 not bad ! 

I set it up for 12 digit floating numbers, not sure if that helped or not.. probably just used to set the display rather than change the internal representation of numbers, I would guess...

So seven zeros... good enough for average engineering needs.

NASA needs better for space navigation ( 150 decimal places IIRC ?? ) but they also have super computers, not pocket calculators....

[mnementh]

You missed the point, V... It should always give back exactly 1... no more, no less.

Anything else means it is rounding incorrectly.

mnem
 

[tautech]

Oh a contest !! 

My old Mk1 TI 85 gives 1.000,000,053,32 not bad ! 

I set it up for 12 digit floating numbers, not sure if that helped or not.. probably just used to set the display rather than change the internal representation of numbers, I would guess...

So seven zeros... good enough for average engineering needs.

NASA needs better for space navigation ( 150 decimal places IIRC ?? ) but they also have super computers, not pocket calculators....

Yes, she was Katherine Johnson.
Watch the movie Hidden Figures. 

[Vince]

The control on the front of the HP 3200B is not the attenuator, it's a vernier control for fine adjustment, you have missed the attenuator as it is hidden as part of the output connector, loosen the knurled nut and the piston attenuator slides out to reduce the output.

Picture above from here; https://sites.google.com/site/rstevescott/home/boatanchor-test-equipment/hp-3200b-vhf-oscillator

I'm after Boonton branded 3200A for my collection, not looked for a while though, more of the 3200A here; http://www.hparchive.com/Boonton/BRC-The-Notebook-37.pdf

Oh and the frequency range switch you said was hard to turn, that is probably due to dried out grease on the various shafts in the mechanism, that operate the switch & turn the scale drum.

2467B update : just gave it a chance... I plugged it back and tried to power it up.... it still works just fine !!!

So the RIFA smoke and fireworks didn't kill it, still works !!!   This scope is a warrior !! 

I guess the RIFA went open circuit rather than shorting, when they released the magic smoke.

Anyway will take it apart soon to fix the PSU. This wonder of a scope deserves a good cleaning and whatever servicing it needs. This thing is not a trouble maker no.. it's an asset in the lab 

The RIFA madness  might not be open circuit, some of them are in series with a resistor, hopefully the board isn't burnt as a result of the resistor burning out, probably best to replace with a fusible/flameproof of the same rating if it's blown too.

David

Oh thanks for that !! So vernier looks like it's working just fine then, great, unit doesn't need fixing in the end !!   

[Vince]

Oh a contest !! 

My old Mk1 TI 85 gives 1.000,000,053,32 not bad ! 

I set it up for 12 digit floating numbers, not sure if that helped or not.. probably just used to set the display rather than change the internal representation of numbers, I would guess...

So seven zeros... good enough for average engineering needs.

NASA needs better for space navigation ( 150 decimal places IIRC ?? ) but they also have super computers, not pocket calculators....

Yes, she was Katherine Johnson.
Watch the movie Hidden Figures. 

Was obviously talking of more modern NASA needs/requirements ! 

EDIT : did a quick search on Google, found this guy from JPL at NASA that say they use Pi with only 15 decimal places, good enough...

https://www.jpl.nasa.gov/edu/news/2016/3/16/how-many-decimals-of-pi-do-we-really-need/

I don't know where I saw that 150 decimal places thing then... was something on TV 15 years ago... maybe that's the precision their computers use for intermediate steps of calculations, so that the sum of all rounding errors, in the end, can guarantee that the final result, with much less decimal places, is accurate. I don't know...

[Robert763]

Plugged the Scopex 4S6 in and it works. Actually very nice trace, bright, sharp and a nice filtered blue/green.
Worth every penny

[Vince]

You missed the point, V... It should always give back exactly 1... no more, no less.

Anything else means it is rounding incorrectly.

mnem
 

I don't nuderstand how you an get an exact 1 if using floating point numbers, which are by their very nature... only an approximation ?
If a calculator gives spot  " 1 " when using floating point number, I guess all it means is it has enough zeros internally to round it to 1 on the display, which shows less digits than the internal representation used  internally for the computation.

IOW your " 1 " is not a one, it's just more zeros than other calculators  so it's rounded to one when displayed...

Plus, from what I understand not every calculator will give the same result for cos / sin / tan depending what algorithm / approximation they use to calculate it ? A trade-off between computing time and available power on the device ?

Isn't that why accounting people use "BCD" calculator so as to get a true result, 100% reliable, to avoid rounding errors inherent to floating point calculation ?

Seems like a rabbit hole to me.. computing nuttery... 

... but it's an interesting subject ! 

[mnementh]

Ehhhh... Ask Z... to a kid who grew up using dial calipers in a world that was engineered using slide rules, those numbers all mean the same thing to me too.

But this was Z's quest, so...

mnem
 

[m k]

A Palmtronic.

BTW,
VT100 case was finally quite flexible.
(roomy)

BTW2,
we are officially tvåspråkiga.

[Specmaster]

I am strong and I resist!

I smell some emu48 there.

What do you get when you do 1 sin cos tan atan acos asin?

I use free42 because it is giving me back 1 at the end....

My DM42 gives "1.00000000". Is that precise enough?

 

Well, my Casio FX-9860G gives me the result of 1, alright, so I have to manually calculate each step and then manually enter the result of the previous step, only because I have not yet had the time or the inclination to learn how to actually program it  .

Always so many other things to be done, but who knows, maybe one day I'll get around to it.

[Saskia]

as an old Unix gal I feel tempted to turn to mnem with the words: "Here's a nickel, kid. go, buy yourself a decent computer ..."

Anyway. Some teasing is  in order.

Returned with an electrically adjustable desk in very good condition for 50 pesos.
yay.
Shipment of Keysight N6700 due tomorrow.

Found some nice speakahs. Quadral Titan Mk 3. Need to find a reason to drive 400 km and spend a couple thou.
Zucca, I have this beautiful high end stereo set here. May I interest you in some beautifully polished Quadral Montan Mk 3 with a proper power amp ?

Need to locate the box with my calculators. There is an HP 48, an HP 49 plus assorted stuff in there. One moving box full of stuff I don't really need.

[ch_scr]

I'm happy to report that Speedcrunch gives 1 as a result of the contest as well.
It sure is neither prestigiuos nor RPN but at least Open Source and available for Win and Linux - portable win version as well,
so it can be used on the work pc without hassle. It's the "happy medium" that has replaced all my dedicated calculating HW. 

[mnementh]

Oh a contest !! 

My old Mk1 TI 85 gives 1.000,000,053,32 not bad ! 

I set it up for 12 digit floating numbers, not sure if that helped or not.. probably just used to set the display rather than change the internal representation of numbers, I would guess...

So seven zeros... good enough for average engineering needs.

NASA needs better for space navigation ( 150 decimal places IIRC ?? ) but they also have super computers, not pocket calculators....

Yes, she was Katherine Johnson.
Watch the movie Hidden Figures. 

Although the movie concentrates on a few African-American women, they had teams of women math-whizzes doing the calculations, and cross-checking against each other. While critically acclaimed, this movie was based on a work of historical fiction, so some dramatic license was taken for the sake of well... dramatization.

mnem
 

[mnementh]

as an old Unix gal I feel tempted to turn to mnem with the words: "Here's a nickel, kid. go, buy yourself a decent computer ..."

Anyway. Some teasing is  in order.

mansaxel already did. I still say "meh".

Besides... I have a perfectly good *NIX box... running El Capitan. That's as close to that particular Kool-Aid as I feel a need to orbit, thanks. 

mnem
this message brought to you by the number ~1 .