Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

Some today arrivals.

Top left: nice Vishay 1MOhm 0.005% resistors (not for me, will forward them to a TEA fellow  )

top middle-right: DC-DC step-down buck converter with voltage display
bought here: https://www.ebay.com/itm/313493568554

The rest: a very nice compilation from ch_scr! Thank you! 
Some PCBs for the AD587UQ and parts. 

[GreyWoolfe]

The test firing was VERY impressive. Must be pretty scary sitting on one when it fires, but then again you would probably be still thinking about whatever caused you to leave the aircraft 

You might be surprised, should you ever have the opportunity to examine the phenomenon first-hand, how much time you have to think, and what you think about when the excrement hits the air moving device at high speed.

I've been involved in two high speed road traffic 'incidents' and both times my perception of time slowed so much I actually had time to consider and make rational choices about how to cope with the situation while enjoying Newtonian mechanics first hand. Time in the immediate aftermath of something like that seems to slow by a factor of 10 or so, so someone who gets to see Martin-Baker's finest in action might well have time to ponder what had just happened, also appreciate the fireworks display, and plan what to do next once the ability of limbs to move catches up with the speed that thought is currently flying by at.

I had that happen in a motorcycle accident once.  A honking big Kawasaki z1000 weighing nearly 500lbs, not a great handling machine on the best of days but crazy fast.  A van turned out on the road in front of me, I was going 70mph and there was nothing I could do...   

Time almost stopped.   I had time to plan everything - how I would flip the bike off the road over the quite high kerb, landing on its side, missing the van...   how the bike then had to slide along the ground through a narrow gap between a tree and a road sign,  into a narrow strip of land that would act as a "landing strip" - while avoiding hitting the brick wall at the end...  I figured out how I had to clutch on to the bike with my knees and thighs, keeping my arms and shoulders tight and straight, letting the motorcycle take the brunt of the friction forces, avoiding sticking any limbs out while the mayhem was going on...

Each step of the plan was executed in what subjectively seemed a veery long time: missing the van and high-siding the bike as planned, falling on its side, missing the tree, missing the road sign, and finally grinding to a halt after several rotations on the narrow strip...  Soil, grass, and stones were spraying everywhere.  Never have I been so grateful for "sissy bars".  As the dust settled, I was still gripping the bike, "sitting" on it as if it was still upright, no part of my body touching the ground.  I got off the bike and stood up.  Not a scratch... the only damage was my pant pocket which got torn off (no skin contact).    The bike was bent out of shape and minus mirrors, turn signals, etc., on the "down" facing side...  but still just about rideable after pulling the handlebar straight again. 

OMG that was one heck of a motorcycle lesson for me, LOL! 

Similar experience in my car when the rear wheels decided to overtake the front wheels at 240 kph. I did several 180s or so while trying to get it back under control and managed to do so. On the way back home I managed to have an average fuel consumption of less than 10l/100. On a supercharged Jag XKR ...
Did not even bend any metal...

Some years back I had a 1992 Ford Explorer 5 speed with oversized tires on it, bought it that way.  On my way home on the highway from a class at the local college, I had an explosive tread separation on the right rear tire.  All I remember was thump, thump, thump, bang and cranking the wheel almost to lock in both directions while trying to keep focused on the road.  Came to a stop in my lane.  After I got to the side of the road, the car behind me stopped to see if I was OK. He said that fishtailed to the right, fishtailed to the left, went up on 2 wheels, came down and spun a 360 all while staying in lane.  It happened so fast I didn't even have time to soil my linen.  Lost all the exhaust pipe back to the muffler and had the rear quarter panel at the bottom behind the wheel well dented in.  Still drove it for awhile until Mrs GreyWoolfe persuaded me to get rid of the 'devil truck' as she called it.

[kj7e]

My lab is kind of a distraction from work, bills, politics and traffic.  Often time I just want to turn knobs and watch needle move, just to see the reaction.

Well, off to work now to deal with inter office politics and LA traffic so I can pay the bills.

[mnementh]

I couldn't list the number of times I've experienced "bullet-time"; I was a bit of a adrenaline-junkie as a youth and if I tried, I'd sound like some drunken ding-dong boasting in a sports bar. 

Having survived the serial stupidity of my own youth, I'm now a old fart with body tore up from the floor up... but for the most part, I wouldn't trade any of it, except for the feeling that I've spent 5 decades waiting for my real life to begin...

mnem
"When you look into the abyss, it looks back into you... and it knows your name." ~mom, paraphrasing Nietzsche

[Cerebus]

Mildred to Ethel: "Ooh, hasn't he got his father's knees!"

[mnementh]

LOL... My dad keeps telling me he's like a carbon-copy duplicate of me when I was a kid. He certainly has the attitude, and the tendency to be utterly oblivious to the world around him. Every once in a while, tho... mother and I are able to impinge upon his existence on "Planet Marcus"; this seemingly normal snapshot is one of them.

mnem
"Eh.... he's a teenager. He won't be human again til his 30s... if he lives that long." ~mom to mom-mom

[Cerebus]

More TEA
I put a low bid on a Rockland /Wavetek Model 442 dual high/low pass filter last night. Ended up winning it for £4.30 and £7 postage 
It looks a bit grubby, is only 2 digit frequency selection (452 is 3 digit), I don't need it but when did that stop me us 

Jammy Git!

I could do with that, or something like it, at the moment. Like you, I thought (note the past tense) that I didn't really have a use for something like that. Now while debugging the GPSDO prototype I've come to the conclusion that my EFC signal is way too noisy and needs some filtering. Now, if I had a good general purpose variable filter on the bench I could have tested that out before building one. As it is, RS deliver the parts for the putative solution tomorrow (didn't have any 5V RIRO op amps handy and needed some suitable caps).

[mnementh]

   

https://insights.globalspec.com/article/16593/watch-caging-mechanism-is-incorporated-into-robotic-hand

Has it really taken us this long to get to this point with robotics...? I had this idea decades ago (even similar construction of the digits & palm surface), and just assumed we had "really smart people" already working on it... 

mnem
 

[Robert763]

Went into work today to supervise use of my Farnell AP60-50 for the first time.  Switched it on. All OK for 10 mnutes and then
Crackle, Hiss, Pop big cloud of smoke and a stink.
One of the RIFAs let go
Told them not to worry about it and carry on. I was a bit more worried about the equipment supplier using a 16A blue CEE male connector on a remote switch - contact between L an E      I was tempted to plug it into the wall and get someone to throw the switch but I think they would not see the funny side.

[mnementh]

D'oh!

I think that must be some unwritten addendum to the usual Murphy's Law/Law of Irony... that "When something can go wrong it will, in the worst possible way at the worst possible time, and in such fashion as to maximize one's potential for embarrassment..."

mnem
"It's been around for decades... it's old enough to smoke if it wants to." ~old man Belmore

[Saskia]

now that you remind me - need to check the B77 for Rifas.

[AVGresponding]

I cant believe someone threw this in the metal waste bin, from where I rescued it. Thankfully the VFD isnt damaged, quick wipedown and then a rough test > seems to be working.

PS: Except current, fails 600.1 and 600.2

These faults are almost certainly dirty contacts on the front/rear input switch. I got mine cheap because of it... not that cheap though!

[FransW]

All Rifa's, in the end, get a "Darwin Award".
Although this does not remove the inheritance.

Where is our Rifa Godfather?

[mnementh]

   https://www.joshuawright.net/slack-wyrm-028.html

I confess... it is me. That isn't magic smoke... it's condensed dwagon farts.

mnem
Do not ask how or why they got in there...

[ch_scr]

Some today arrivals.

Top left: nice Vishay 1MOhm 0.005% resistors (not for me, will forward them to a TEA fellow  )

top middle-right: DC-DC step-down buck converter with voltage display
bought here: https://www.ebay.com/itm/313493568554

The rest: a very nice compilation from ch_scr! Thank you! 
Some PCBs for the AD587UQ and parts. 

Glad it arrived well, here's the help for putting the components on:
Note  : where the 2 parallel 100R's reside is the trim for the "farther than the other" AD587.
The one thats off the other way got 2 in series. On the three other ones just one 100R and a bridge for the trimpot was "good enough"
Note 2: The place that looks like it wants to have the 100R SMD trim, needs a bridge. The cut away trace gets the 100R.
(As seen in the picture below) Go figure 
Note 2.5: The solder pads for the ferrite beads are a bit short, but you'll find a way to get them on I'm sure 
Note 3: "Every solder job looks shoddy, given you magnify enough" ~ proverb of the magnifier salesman
Have fun!

[AVGresponding]

Picked up a quirky little counter on a maiden bid this last week, largely to keep it away from the nixie clock wankers.



It needs a little fettling; the power switch is jammed on for one thing, and I think all the controls could benefit from some contact cleaner, the BNCs as well.


Ironically enough, while I was playing with it I got the idea that it would be an interesting challenge to make it work as a clock display, without modifying it in any way...   

[mnementh]

I've suggested that as a project in here several times. 

mnem
"Sick minds think alike. And you're more likely than most..." ~grand-dad

[mnementh]

Ehhhh... it's just another fuckkin' ugly scope from the caveman days. Who fucking cares...?   

mnem
Yes, I would dump a jar of scorpions out in a lifeboat just to see who could swim...

Wash yo mouf out Dwagon!

I do,

Frans

Of course, we all know I only said that because it was too quiet in here... 

mnem
*agitator-dwagon*

[AVGresponding]

Ironically enough, while I was playing with it I got the idea that it would be an interesting challenge to make it work as a clock display, without modifying it in any way...   

I've suggested that as a project in here several times. 

mnem
"Sick minds think alike. And you're more likely than most..." ~grand-dad

Extra kudos points if you can do it by tickling the VCO input of a 555

[BU508A]

Some today arrivals.

Top left: nice Vishay 1MOhm 0.005% resistors (not for me, will forward them to a TEA fellow  )

top middle-right: DC-DC step-down buck converter with voltage display
bought here: https://www.ebay.com/itm/313493568554

The rest: a very nice compilation from ch_scr! Thank you! 
Some PCBs for the AD587UQ and parts. 

Glad it arrived well, here's the help for putting the components on:
Note  : where the 2 parallel 100R's reside is the trim for the "farther than the other" AD587.
The one thats off the other way got 2 in series. On the three other ones just one 100R and a bridge for the trimpot was "good enough"
Note 2: The place that looks like it wants to have the 100R SMD trim, needs a bridge. The cut away trace gets the 100R.
(As seen in the picture below) Go figure 
Note 2.5: The solder pads for the ferrite beads are a bit short, but you'll find a way to get them on I'm sure 
Note 3: "Every solder job looks shoddy, given you magnify enough" ~ proverb of the magnifier salesman
Have fun!

I've drawn a little schematic. To your eyes, does it look correct?

The two parallel 100 Ohms resistors are in my schematic R1, right?

[mnementh]

Ironically enough, while I was playing with it I got the idea that it would be an interesting challenge to make it work as a clock display, without modifying it in any way...   

I've suggested that as a project in here several times. 

mnem
"Sick minds think alike. And you're more likely than most..." ~grand-dad

Extra kudos points if you can do it by tickling the VCO input of a 555

   https://shop.evilmadscientist.com/productsmenu/tinykitlist/652#

mnem
 

[factory]

Picked up a quirky little counter on a maiden bid this last week, largely to keep it away from the nixie clock wankers.



It needs a little fettling; the power switch is jammed on for one thing, and I think all the controls could benefit from some contact cleaner, the BNCs as well.


Ironically enough, while I was playing with it I got the idea that it would be an interesting challenge to make it work as a clock display, without modifying it in any way...   

I've got one of those too, the power switch is at the back with a rod to actuate it.
You may find it more tricky trying to add the sixth digit, this counter uses some odd counter IC's on the display board, circuit diagrams for the 7736 version here; https://vintage-radio.net/forum/showpost.php?p=627900&postcount=22

David

[ch_scr]

Some today arrivals.

Top left: nice Vishay 1MOhm 0.005% resistors (not for me, will forward them to a TEA fellow  )

top middle-right: DC-DC step-down buck converter with voltage display
bought here: https://www.ebay.com/itm/313493568554

The rest: a very nice compilation from ch_scr! Thank you! 
Some PCBs for the AD587UQ and parts. 

Glad it arrived well, here's the help for putting the components on:
Note  : where the 2 parallel 100R's reside is the trim for the "farther than the other" AD587.
The one thats off the other way got 2 in series. On the three other ones just one 100R and a bridge for the trimpot was "good enough"
Note 2: The place that looks like it wants to have the 100R SMD trim, needs a bridge. The cut away trace gets the 100R.
(As seen in the picture below) Go figure 
Note 2.5: The solder pads for the ferrite beads are a bit short, but you'll find a way to get them on I'm sure 
Note 3: "Every solder job looks shoddy, given you magnify enough" ~ proverb of the magnifier salesman
Have fun!

I've drawn a little schematic. To your eyes, does it look correct?

The two parallel 100 Ohms resistors are in my schematic R1, right?

First glance says: except L3's a diode it's correct
Edit says: good job on the davecad 

[AVGresponding]

   https://shop.evilmadscientist.com/productsmenu/tinykitlist/652#

mnem
 

Interesting, but if you're going to emulate a 555 with discrete devices, then for a nixie clock project you need to use toobs...

[Cerebus]

Picked up a quirky little counter on a maiden bid this last week, largely to keep it away from the nixie clock wankers.



It needs a little fettling; the power switch is jammed on for one thing, and I think all the controls could benefit from some contact cleaner, the BNCs as well.


Ironically enough, while I was playing with it I got the idea that it would be an interesting challenge to make it work as a clock display, without modifying it in any way...   

Then your next step is to decide how hard a challenge you want:

• Easy - Frequency controlled - digital - based around a DDS or similar
• Easyish - Frequency controlled - digital - based around generating the right pulse train.
• Middling - Timing controlled - digital - based around just generating the right pulse width with an MCU
• Hard - timing controlled - analogue controlled pulse generator with a digital source of "time"
• Fiendishly hard - timing controlled - analogue controlled pulse generator with an analogue source of "time"