Recent Posts

1

Test Equipment / Re: Second bench PSU, am I thinking about this correctly?

« Last post by J-R on Today at 07:21:33 pm »

In my opinion, for a bench supply I could not see the point of getting a 6624A or similar, even if you had GAS.  It's big, heavy and loud.  You don't get any of the modern features like USB, ethernet and web browser control.  These negatives also apply to many of the other HP/Agilent supplies that frequently get mentioned.
https://www.eevblog.com/forum/testgear/agilent-6624a/

The Rigol DP800 & now DP900 series units are popular but the circular keypad might take some getting used to.  These are also not necessarily "cheap", but maybe one will hit the clearance rack or eBay.  Both can be hacked:
https://www.eevblog.com/forum/testgear/need-help-hacking-dp832-for-multicolour-option/
https://www.eevblog.com/forum/testgear/rigol-dp900-dp2000-series-hack/

If you want to flex your budget a bit, check out the GW Instek GPP-4323.  It has some oddities as well but otherwise could be of interest.  It also has a load function.  It seems there are various permutations with jack & ethernet options.
https://www.eevblog.com/forum/testgear/just-bought-a-gw-instek-gpp-4323-power-supply-first-impressions-etc/
https://www.eevblog.com/forum/testgear/gw-instek-gpp-4323-422471/

2

Beginners / Re: uCurrent Gold Schematic

« Last post by xvr on Today at 07:18:52 pm »

> I have placed NMOS in antiparallel with the lowest shunt resistor for protection.

For which protection? In current configuration lower shunt resistor will be always turned on by body diode of Q1 or Q4.
Also Gate of Q1 now referred not to ground of whole schema (as should be) but again high pin of current input terminal

3

RF, Microwave, Ham Radio / Re: Transistor tester

« Last post by madires on Today at 07:18:49 pm »

Those chinese testers work so-so with Ge trannies.

Their firmware is based on an older version of the OSHW k-firmware with issues discerning Ge BJTs from JFETs. If you have a tester with a genuine ATmega you could flash the m-firmware which comes with a few additional checks to tell Ge BJTs and JFETs apart.

4

Test Equipment / Re: Choosing between entry-level 12-bit DSOs

« Last post by KungFuJosh on Today at 07:17:20 pm »

the limited framerate of the web console.

Yeah that can be an unpleasant obstacle to a demonstration of a frequency sweep. What's the frame rate, anyway? Is it worse than 30 fps?

Yes, I assume it's around 15 fps, but I don't know. I wish they made the framerate selectable.

5

General Technical Chat / Re: Your pet peeve, technical or otherwise.

« Last post by DimitriP on Today at 07:16:25 pm »

I bought a passive audio channel switch box on Amazon.

After 3 weeks the selector buttons became intermittent and scratchy.

I said that in the review.

"Your review has been rejected because of reasons."

Resubmit it to Amazon
Add amazon, comanay name and model to your post
Even if Amazon rejects it, google will find it.

6

Test Equipment / Re: Choosing between entry-level 12-bit DSOs

« Last post by shapirus on Today at 07:15:07 pm »

the limited framerate of the web console.

Yeah that can be an unpleasant obstacle to a demonstration of a frequency sweep. What's the frame rate, anyway? Is it worse than 30 fps?

7

Test Equipment / Re: Choosing between entry-level 12-bit DSOs

« Last post by shapirus on Today at 07:13:43 pm »

and the display persistence hides the deviation of the peaks from the real value.

Persistence will not hide the peaks, it will tend to broaden the trace to include both peaks and the troughs and everything in between over the period of persistence.  Maybe you are thinking of averaging?

We're talking about the same thing, but from different perspective. Yes, the more the amplitude varies, the wider the trace at the peaks becomes. If we want to conveniently see the spread over a period of time, that's where persistence helps. It's like seeing min/max/avg values in the same place.

My screenshots in previous posts show an opposite approach, where a single capture shows how the scope interprets the wave at a single given acquisition.

8

Security / Re: Microsoft repackages apps with a telemetry .NET wrapper

« Last post by tooki on Today at 07:11:27 pm »

So what I mean is that a proper opt-in system makes it clear that the software isn’t, for example, uploading your document to them.

What will prevent to collect the data independently on that opt-in setting?

Not sure what you mean.

Point is, a well written opt-in makes it CLEAR to the user who is reading it what will and will not be collected and uploaded, and what happens to it once uploaded, so that the user can make an informed decision on whether to click “allow” or “decline”.

The same as it happens with MS?

Meaning what? MS has multiple different telemetry systems with separate opt-ins, some for the user, some for the developer to see. This thread is about one where a developer wasn’t paying attention and got their panties in a twist over something they didn’t read when setting up their installer.

9

Beginners / Re: uCurrent Gold Schematic

« Last post by uf29857 on Today at 07:07:35 pm »

Thanks for poinitng it out. I forgot to connect output feedback.
I have placed NMOS in antiparallel with the lowest shunt resistor for protection.
Q1 will check again and will remove it as suggested in the previous comment.

10

Repair / Re: Looking for a small PCB-mount microswitch with a long stem

« Last post by tooki on Today at 07:04:15 pm »

You’re not finding them because these are not called microswitches. Panasonic calls them “detector switches”, Omron “detection switches”. Look at https://www.digikey.com/short/hv315jf2