Test Equipment Anonymous

bd139 wrote: ↑Sun Sep 08, 2024 10:32 am

Zenith wrote: ↑Sun Sep 08, 2024 10:13 am At Telford last weekend I was tempted to buy a Tek 7400 series scope with plugins for £10 to take to bits. A bit big and heavy though.

I'd have bought that Tek

Bit big and heavy to carry on a train/tube/etc

Bad enough up stairs

tggzzz wrote: ↑Sun Sep 08, 2024 12:56 pm

bd139 wrote: ↑Sun Sep 08, 2024 10:32 am

Zenith wrote: ↑Sun Sep 08, 2024 10:13 am At Telford last weekend I was tempted to buy a Tek 7400 series scope with plugins for £10 to take to bits. A bit big and heavy though.

I'd have bought that Tek

Bit big and heavy to carry on a train/tube/etc

Bad enough up stairs

I have a trolley and a lift

bd139 wrote: ↑Sun Sep 08, 2024 1:45 pm

tggzzz wrote: ↑Sun Sep 08, 2024 12:56 pm

bd139 wrote: ↑Sun Sep 08, 2024 10:32 am

I'd have bought that Tek

Bit big and heavy to carry on a train/tube/etc

Bad enough up stairs

I have a trolley and a lift

A Weightlifter's belt would be a useful addition.

Zenith wrote: ↑Sun Sep 08, 2024 3:57 pm

bd139 wrote: ↑Sun Sep 08, 2024 1:45 pm

tggzzz wrote: ↑Sun Sep 08, 2024 12:56 pm

Bit big and heavy to carry on a train/tube/etc

Bad enough up stairs

I have a trolley and a lift

A Weightlifter's belt would be a useful addition.

And some knees and a spine

bd139 wrote: ↑Mon Aug 26, 2024 10:53 pm From what I know of the Soviet defence sector, the persistence of the things is because they had regulatory requirement to be able to be self-sufficient as a nation and they had a lot of stock left lying around. On top of that the cost was much lower than newer technology.

Suitable meme


cJpvQY1.jpeg


That reminds me I must buy something stupid and soviet...

Multitasking as well, a space heater and LED, very efficent.

Zenith wrote: ↑Sun Sep 08, 2024 10:16 am

mnementh wrote: ↑Sat Sep 07, 2024 4:14 pm Calling Cubdriver... calling Cubdriver...

Been here all morning; everybody's pretty much gone. Did I walk right past and not recognize you?

mnem

What prizes did you come away with?

A few bits and bobs...
mnem
continued next post...

continued...
I spent a grand total of $57, including sodas and doughnuts.

mnem

Nice haul - those cabinets are very useful.

Were you able to reconfigure those acdc electronics supplies to work on 120 V? They came from a Silent Key up in New Hampshire. He'd been a UHF TV station guy, I suspect they came from a transmitter. I'm a pack rat; he made me look like a rank amateur!

-Pat

I'd have been pleased with that.

Cubdriver wrote: ↑Thu Sep 12, 2024 1:44 am Nice haul - those cabinets are very useful.

Were you able to reconfigure those acdc electronics supplies to work on 120 V? They came from a Silent Key up in New Hampshire. He'd been a UHF TV station guy, I suspect they came from a transmitter. I'm a pack rat; he made me look like a rank amateur!

-Pat

Yeah, that's what I'm doing here, tho my intent is not to use the supplies as-is; they're dag-nasty full of black mold anyways. I want these bits for a dual bench supply/charger project I've had on the back burner since before I left the GWN.

1-->7 is the original 230V primary; 1-->6 appears to be the 120V winding. 2-->6 brings output up 4-5V, so I'd guess that would be the 0V tab for 110V/220V applications.

mnem
They have a wicked little standalone crowbar circuit on them; I might put that in the "for future deviltry" bin...

54600 by itself on middle shelf above microscope

As an aside... the 54600 now has a new home; a "pay it forward" gift to a teenager who was there pack-ratting leftovers at the end of the day.

I saw him and his mum chasing after him; so I spent some time talking with her while he was wandering around the museum. He's "on the spectrum" (this was evident from his behavior and from talking with him while I was browsing the same leftovers) and tinkering with electronics is one of the few activities that makes him settle down.

I saw a lot of similarities to myself as a school kid; I was diagnosed as "hyperactive" and pumped full of Ritalin while in grade school, and had started tinkering with all things mechanical at an early age. I credit the kindness of my high school's head of AV & Repair Dept with getting me started in electronics; the gift of some basic tools and a bit of benchtime after my cores every day helped both my attentiveness in class and my socialization.

Mum and I talked aboot similar behaviors in him, and I decided this was someone who could definitely benefit from having a decent working scope, so we packed it away in the trunk of her car as a surprise once he got home.

Hopefully it will help him get a similar start down a productive road in life...

mnem
be the change you want to see in the world.

It reminds me of this.

https://www.youtube.com/watch?v=Dx6HojLBsnw

mnementh wrote: ↑Wed Sep 11, 2024 11:52 pm
IMG_20240907_114139_426~2.jpg

What are you going to do with that horrible gargoyle inflatable thing you came away with? I suppose it might come in handy at Halloween, or you might blow it up and leave it around to put off burglars when you are away.

mnementh wrote: ↑Thu Sep 12, 2024 5:23 pm Mum and I talked aboot similar behaviors in him, and I decided this was someone who could definitely benefit from having a decent working scope, so we packed it away in the trunk of her car as a surprise once he got home.

Hopefully it will help him get a similar start down a productive road in life...

Lovely idea; good for you!

I hope he won't use it to measure the mains.

tggzzz wrote: ↑Thu Sep 12, 2024 9:33 pm

mnementh wrote: ↑Thu Sep 12, 2024 5:23 pm Mum and I talked aboot similar behaviors in him, and I decided this was someone who could definitely benefit from having a decent working scope, so we packed it away in the trunk of her car as a surprise once he got home.

Hopefully it will help him get a similar start down a productive road in life...

Lovely idea; good for you!

I hope he won't use it to measure the mains.

I concur on the kudos. Mnem is a kind person with an eye out for the needing.

Then, 120V is not a problem Especially not if he manages to put it the right way around... Here, though:

tggzzz wrote: ↑Thu Sep 12, 2024 9:33 pm

mnementh wrote: ↑Thu Sep 12, 2024 5:23 pm Mum and I talked aboot similar behaviors in him, and I decided this was someone who could definitely benefit from having a decent working scope, so we packed it away in the trunk of her car as a surprise once he got home.

Hopefully it will help him get a similar start down a productive road in life...

Lovely idea; good for you!

I hope he won't use it to measure the mains.

Part of growing up is to get a belt off 240V mains. It teaches you to be careful. Once received, never forgotten. Just make sure you are not standing in bare feet on a wet kitchen floor. I'm certainly not recommending it as a rite of passage or anything like that.

I've heard those £5 el cheapo DMMs can flash over when measuring mains. Copper dust accumulates from the range switch and boom! Distressing, but almost certainly not dangerous.

Yeah, from one hand to the other, in one case

My concern is more about where a probe's shield goes.

BTW, those multimeter are squaddyproof. Bd made a video where he used one to forcibly insert a dowel.

I looked into this years ago, but there wasn't any authoritative information I could find in one place.

I recall an IEEE study which said there was no definite case of electrocution involving less than 30mA across the heart. AC at 50 or 60Hz was particularly dangerous and more so than DC at the same voltage. Dry skin is a poor conductor, but AC accelerates sweating enormously. There were cases of people fatally electrocuted with the 36V mains used on some US farms. I can imagine someone working with wet feet and wet hands, maybe with cuts, presenting an ideal subject for electrocution.

There were very few, maybe five people a year, killed by electrocution by contact with the mains in the UK, over a ten year period.

Getting a hand to hand shock is particularly dangerous.

Of course, one of the dangers of getting a non-lethal shock, is the involuntary reflex which could throw a limb in the way of moving parts or cause a fall onto something.

Pre-war TVs were known as Widow Makers. The EHT came directly from a winding on a mains transformer at 4kV. It's easy to see that delivering far more than 30mA for as long as it would take to kill.

There's a dangerous craze for fractal wood burning, using microwave transformers.

https://www.youtube.com/watch?v=EAHAfmY ... tingHorror

Several people have been killed.

I was lucky; a light touch, then the involuntary rapid muscle contraction broke contact.

Zenith wrote: ↑Fri Sep 13, 2024 8:02 pm

tggzzz wrote: ↑Thu Sep 12, 2024 9:33 pm

mnementh wrote: ↑Thu Sep 12, 2024 5:23 pm Mum and I talked aboot similar behaviors in him, and I decided this was someone who could definitely benefit from having a decent working scope, so we packed it away in the trunk of her car as a surprise once he got home.

Hopefully it will help him get a similar start down a productive road in life...

Lovely idea; good for you!

I hope he won't use it to measure the mains.

Part of growing up is to get a belt off 240V mains. It teaches you to be careful. Once received, never forgotten. Just make sure you are not standing in bare feet on a wet kitchen floor. I'm certainly not recommending it as a rite of passage or anything like that.

I've heard those £5 el cheapo DMMs can flash over when measuring mains. Copper dust accumulates from the range switch and boom! Distressing, but almost certainly not dangerous.

I got belted by 208VAC at work. Once. That's all it took to work smarter and safer. It hurt like a mofo.
,

Zenith wrote: ↑Thu Sep 12, 2024 9:05 pm

mnementh wrote: ↑Wed Sep 11, 2024 11:52 pm
IMG_20240907_114139_426~2.jpg

What are you going to do with that horrible gargoyle inflatable thing you came away with? I suppose it might come in handy at Halloween, or you might blow it up and leave it around to put off burglars when you are away.

Not really a lot I can do; belongs to SWMBO along with my grumpy old soul. At least she lets me take off the mask once a year...

mnem

tggzzz wrote: ↑Thu Sep 12, 2024 9:33 pm

mnementh wrote: ↑Thu Sep 12, 2024 5:23 pm Mum and I talked aboot similar behaviors in him, and I decided this was someone who could definitely benefit from having a decent working scope, so we packed it away in the trunk of her car as a surprise once he got home.

Hopefully it will help him get a similar start down a productive road in life...

Lovely idea; good for you!

I hope he won't use it to measure the mains.

Well, I did take the precaution of giving him only a pair of 10X probes with it.

mnem
tzzzzzzt.

tggzzz wrote: ↑Fri Sep 13, 2024 9:11 pm Yeah, from one hand to the other, in one case

My concern is more about where a probe's shield goes.

BTW, those multimeter are squaddyproof. Bd made a video where he used one to forcibly insert a dowel.

Yeah, not gonna doo datt with my ex-USMC 27.

mnem

mnementh wrote: ↑Fri Sep 13, 2024 11:24 pm

tggzzz wrote: ↑Thu Sep 12, 2024 9:33 pm I hope he won't use it to measure the mains.

Well, I did take the precaution of giving him only a pair of 10X probes with it.

Sorry, I have to be boring and I know I'm teaching you how to suck eggs.



Posting a yootoob vid. Oh, the indignity!

Some HP binders/manuals for the price of shipping in the US: https://www.eevblog.com/forum/buysellwa ... l-binders/