Test equipment is a disease...

[BillyO]

I have at my disposal no less than 4 wonderful pro-level bench power supplies.  A pretty good low end unit and a fairly nice DIY one I just finished building.

Guess what I spent all day on today?  Yup, designing an even better DIY bench power supply!!!

Help me!

[TomKatt]

Don't look at me for help - I got curious why I was having trouble plugging a differential probe into the usb port of my scope for power and now I'm building a current probe setup to investigate something that could be solved simply by plugging it into a wall wart...  Meanwhile my original task gets completely sidelined and my online shopping carts are filling up with new gear.

It never ends ;-)

[Martin72]

Hi BillyO,

https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/


Edit: Bla.

[jjoonathan]

Re: "how much power can I get out of a scope USB port to power my probe," I was measuring exactly this just the other day by using my N6705B as a fancy graphing electronic load.

https://www.dropbox.com/scl/fi/n668g389bo57tq4e5ogu8/Probe-Pwr.pdf?rlkey=9ysljk45tm4tg444gzu9sgv1o&st=r7l5gds9&dl=0

so clearly you should just buy more equipment. What's that? You aren't made of money? Well there's a "cheap" and "broken" (i.e. "adventure model") one on eBay right now! Hurry hurry hurry! Just think of all the money you could saaaaaaavvvveee 

EDIT: ebay link removed due to compliance with Test Equipment Voluntary Self-Exclusion Program

[TomKatt]

Re: "how much power can I get out of a scope USB port to power my probe," I was measuring exactly this just the other day by using my N6705B as a fancy graphing electronic load.

https://www.dropbox.com/scl/fi/n668g389bo57tq4e5ogu8/Probe-Pwr.pdf?rlkey=9ysljk45tm4tg444gzu9sgv1o&st=r7l5gds9&dl=0

Not to derail the topic, but thanks!  Very interesting - I cannot believe I'm going over an amp...  Clearly I've got more investigating to do lol.

And don't tempt me like that !!! 

[jjoonathan]

The overcurrent protection is pretty quick, it might have triggered on inrush surge. The USB chip on my scope (USB2517, the proprietary probe interface is just USB + 2 pins) supported the following timings:

Code: [Select]

5:4 OC_TIMER Over-Current Timer: Over-Current Timer delay.

00=0.1ms
01=4ms
10=8ms
11=16ms
You can see from my measurements (17.8ms cutout) that it was programmed to the longest delay, not shortest.

[Martin72]

Guys, things are getting a bit wild here...

Edit: Bla.

[TomKatt]

Guys, things are getting a bit wild here...

It's a disease!

[jjoonathan]

It's not the polychlorinated compounds in my brain speaking, it's the practical time savings on every occasion I have to make dynamic power measurements... on another piece of test equipment 

[EEVblog]

I have at my disposal no less than 4 wonderful pro-level bench power supplies.

Only 4? 

[Martin72]

Guys, things are getting a bit wild here...

That obviously doesn't matter if even the “boss” is involved.
Accordingly, I withdraw my previous posts.

[tautech]

Test equipment is a disease...

And you are blind without it !
Some of us are fortunate to live, eat and breathe it. 
 

[CatalinaWOW]

But no piece of gear does everything perfectly, and there is always that one measurement you can't quite do right or easily with what you have at hand.

[KungFuJosh]

Or you buy an SPD3303X that you didn't need, and find out it's the older problematic hardware so now you want to buy an electronic load to test while it's still in warranty.

[EEVblog]

Or you buy an SPD3303X that you didn't need, and find out it's the older problematic hardware so now you want to buy an electronic load to test while it's still in warranty.

[ballsystemlord]

I have at my disposal no less than 4 wonderful pro-level bench power supplies.  A pretty good low end unit and a fairly nice DIY one I just finished building.

Guess what I spent all day on today?  Yup, designing an even better DIY bench power supply!!!

Help me!

Hey, as long as you post about it (inc schematics), then you can honestly say that you're taking one for the team -- and loving it!

[BillyO]

I have at my disposal no less than 4 wonderful pro-level bench power supplies.

Only 4? 

I know, I suck.  Hey, I've only been at this since my 2nd retirement 2 years ago!!!

Now I'm taking on jobs again..

I'll never learn.

[BillyO]

Or you buy an SPD3303X that you didn't need, and find out it's the older problematic hardware so now you want to buy an electronic load to test while it's still in warranty.

Did that already...

[BillyO]

Accordingly, I withdraw my previous posts.

I enjoyed the first one for at least 10 pages..

[BillyO]

Hey, as long as you post about it (inc schematics), then you can honestly say that you're taking one for the team -- and loving it!

We'll see how the prototypes work out.  Never like to bend over with my knickers down!

[artag]

It's not just test equipment

When I'm holding your wheel
All I hear is your gear
When my hand's on your grease gun
Oh, it's like a disease, son

[moerm]

I have at my disposal no less than 4 wonderful pro-level bench power supplies.  A pretty good low end unit and a fairly nice DIY one I just finished building.

Guess what I spent all day on today?  Yup, designing an even better DIY bench power supply!!!

Help me!

Sorry, can't, wrong address. Help from a guy who designed all his supplies, currently 8 (or 4 dual, plus a MV and HV one) himself? No way.
You see, IMO one absolutely needs at least two dual low amp supplies plus a mid range one (3 or 4 Amps), all the usual range (30-ish V) plus, just in case, a dual >= 7 A (mine: 10 A), all linear as it befits a lab. Plus of course, a 500-ish V (abt 1 A), plus, being at it, a 10 x multiplier. All with a decent meter (14 bits).
And I'm bloody sure that I'm still missing something.

The culprit: An EE with lots and lots of experience whom I revered, who sternly told me that an electronician worth his salt builds his own PSUs when I asked him about a certain (commercial) PSU I intended to save for.

[pdenisowski]

I have at my disposal no less than 4 wonderful pro-level bench power supplies.

Only 4? 

But have you connected all the ports in series yet?