Recent Posts

1

EEVblog Specific / Re: EEVblog 1612 - Siglent SDS1000X HD 12 bit Oscilloscope Teardown

« Last post by EEVblog on Today at 12:05:06 am »

There seems to be another plastic film on the surface of the screen (?). Apparently a residue left on the surface of the screen during installation, and then the film marked with a red ribbon was put on top. Please check  it. Surface need look same half matte as SDS800. Least I have not seen this glossy surface  in SDS1000XHD what can see in your video.

Wow, you are right. less reflective now with it removed. I've never seen two films like that before.

2

Repair / Re: Tektronix DM501A repair

« Last post by David Hess on Today at 12:05:03 am »

They all have slightly different signs of trouble, but essentially nothing works well, starting with non-sensical display annunciations.

If I am reading your DSO correctly, the clock signal at pin 8 is completely wrong, and does not even meet the duty cycle requirements.

3

Projects, Designs, and Technical Stuff / Re: more modern version of tl494?

« Last post by xavier60 on Yesterday at 11:59:37 pm »

I have a strong preference for the UC3525.
It is reassuring to see in the internal block diagram, the steering flip-flop being clocked directly by the oscillator and also the latch at the comparator's output.
Not so for the TL598 despite the claims. The extra opamp might seem useful but can be difficult to achieve fast current limiting with it.
With the UC3525, I implement fast pulse-by-pulse limiting by pulling down the soft-start pin.

4

Beginners / Re: Question about use of Differential using scope USB port

« Last post by David Hess on Yesterday at 11:41:03 pm »

A differential probe *must* be grounded to the oscilloscope to control its common mode input voltage.  If it was isolated, then its common mode voltage could drift out of range and present a safety hazard itself.  So the connection to the USB port is not a concern because the probe will be grounded through the BNC connection anyway.

Manufacturers who make oscilloscopes that have galvanically isolated inputs warn about using differential probes with them unless they can be separately grounded to the oscilloscope.

5

Power/Renewable Energy/EV's / Re: 5 out of 6 vendors are scamming people with wrong crosssection of cables

« Last post by ejeffrey on Yesterday at 11:38:52 pm »

No, because I order from Digikey/Mouser/Farnell.

When there are so many cases of wrong cross sections, i would be very curious not caring about big names.

I've never measured explicitly, but if you told me you bought genuine belden wire from and authorized distributor and it was smaller than what it says on the box I'd be surprised and I would go measure some of the wires in my shop.  The fact that 5 different wires purchased from random resellers on Amazon or eBay were counterfeit it doesn't surprise me at all.

6

Test Equipment / Re: Troubles with HP-8903B

« Last post by Tony_G on Yesterday at 11:37:26 pm »

Great response SRB - Way more useful than my quick, "here is what my working one looks like" post.

Look forward to the results here.

TonyG

7

Test Equipment / Re: Siglent SSA 3021X... Ooops

« Last post by tautech on Yesterday at 11:35:37 pm »

Have you considered working through some of the performance verification steps in the service manual ?

8

Test Equipment / Re: SDS800X HD Wanted Features

« Last post by KungFuJosh on Yesterday at 11:28:49 pm »

Any advanced user with some active Math channels.

A few more words would have been useful, and would have sounded much nicer...

From the guy who always tells me he prefers short answers to long winded ones. 😉😉

9

Microcontrollers / Re: Has anyone used ASAN & MSAN, and relevance to embedded arm32

« Last post by tellurium on Yesterday at 11:28:36 pm »

GCC can do static stack usage analysis. Just add "-fstack-usage" to the build flags, then GCC spits BINARY.su file with data.

10

General Technical Chat / Re: Russia and China to Build a Nuclear Plant on the Moon.

« Last post by SiliconWizard on Yesterday at 11:28:31 pm »

Well, conflating "non-visible" with "dark" was a case of ostrich policy.

"There is no dark side of the moon really. Matter of fact it's all dark."